Seattle to Denver (DEN) flight deals

Seattle (SEA) to Denver (DEN): round-trip and one-way prices for 90 departure dates, Nov 10, 2026–Feb 7, 2027. One adult, economy. Open a departure for return options; use the chooser below for other travelers and cabins.

Frontier Airlines, nonstop, from $140 round trip · Southwest Airlines, nonstop, from $245 round trip

Saved nonstop flight times: 2h 30m–2h 48m outbound; 3h 8m–3h 10m returning.

How to read the calendar: published Axel-exclusive USD totals for one adult, including required taxes; basic economy may apply. Each return range includes its own prices. Only the listed dates and options are priced. Date links open published details; live search checks availability and lets you select flights.

Months at a glance

November 2026: Nov 10 from $245 · Nov 11 from $140 · Nov 12 from $245 · Nov 13–15 from $140 · Nov 16–17 from $245 · Nov 18 from $140 · Nov 19 from $245 · Nov 20–22 from $140 · Nov 23 from $245 · Nov 24 from $294 · Nov 25 from $168 · Nov 26 from $294 · Nov 27–29 from $168 · Nov 30 from $294.

December 2026: Dec 1 from $245 · Dec 2 from $140 · Dec 3 from $245 · Dec 4–6 from $140 · Dec 7–8 from $245 · Dec 9 from $140 · Dec 10 from $245 · Dec 11–12 from $140 · Dec 13–15 from $245 · Dec 16 from $140 · Dec 17 from $245 · Dec 18 from $164.50 · Dec 19 from $196 · Dec 20 from $343.01 · Dec 21 from $171.50 · Dec 22 from $300.13 · Dec 23 from $171.50 · Dec 24 from $300.13 · Dec 25–26 from $171.50 · Dec 27 from $300.13 · Dec 28 from $164.50 · Dec 29 from $287.88 · Dec 30 from $164.50 · Dec 31 from $287.88.

January 2027: Jan 1–2 from $164.50 · Jan 3 from $287.88 · Jan 4 from $140 · Jan 5 from $245 · Jan 6 from $140 · Jan 7 from $245 · Jan 8–9 from $140 · Jan 10 from $245 · Jan 11 from $140 · Jan 12 from $245 · Jan 13 from $140 · Jan 14 from $245 · Jan 15–16 from $140 · Jan 17 from $245 · Jan 18 from $140 · Jan 19 from $245 · Jan 20 from $140 · Jan 21 from $245 · Jan 22–23 from $140 · Jan 24 from $245 · Jan 25 from $140 · Jan 26 from $245 · Jan 27 from $140 · Jan 28 from $245 · Jan 29–30 from $140 · Jan 31 from $245.

February 2027: Feb 1 from $140 · Feb 2 from $245 · Feb 3 from $140 · Feb 4 from $245 · Feb 5–6 from $140 · Feb 7 from $245.

Month summaries show the lowest displayed round-trip total for each departure. Match your return date to the calendar below.

November 2026 · SEA → DEN

USD · 1 adult · economy · published Oct 29, 2026

Tue, Nov 10, 2026 · round trip · return Nov 11–23: Southwest Airlines $245 / Alaska $250, nonstop; return Nov 24: Southwest Airlines $294 / Alaska $300, nonstop · one-way: Southwest Airlines $130, nonstop

Wed, Nov 11, 2026 · round trip · return Nov 12: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Nov 13–18: Frontier Airlines $140 / Alaska $250, nonstop; return Nov 19: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Nov 20–23: Frontier Airlines $140 / Alaska $250, nonstop; return Nov 24–25: Frontier Airlines $168 / Alaska $300, nonstop · one-way: Frontier Airlines $75, nonstop

Thu, Nov 12, 2026 · round trip · return Nov 13–23: Southwest Airlines $245 / Alaska $250, nonstop; return Nov 24–26: Southwest Airlines $294 / Alaska $300, nonstop · one-way: Southwest Airlines $130, nonstop

Fri, Nov 13, 2026 · round trip · return Nov 14–18: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Nov 19: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Nov 20–23: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Nov 24–25: Frontier Airlines $168 / Southwest Airlines $294, nonstop; return Nov 26: Frontier Airlines $196, out: nonstop, back: 1 stop via LAS / Southwest Airlines $294, nonstop; return Nov 27: Frontier Airlines $168 / Southwest Airlines $294, nonstop · one-way: Frontier Airlines $75, nonstop

Sat, Nov 14, 2026 · round trip · return Nov 15–18: Frontier Airlines $140 / Alaska $250, nonstop; return Nov 19: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Nov 20–23: Frontier Airlines $140 / Alaska $250, nonstop; return Nov 24–25: Frontier Airlines $168 / Alaska $300, nonstop; return Nov 26: Frontier Airlines $196, out: nonstop, back: 1 stop via LAS / Alaska $300, nonstop; return Nov 27–28: Frontier Airlines $168 / Alaska $300, nonstop · one-way: Frontier Airlines $75, nonstop

Sun, Nov 15, 2026 · round trip · return Nov 16–18: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Nov 19: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Nov 20–23: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Nov 24–25: Frontier Airlines $168 / Southwest Airlines $294, nonstop; return Nov 26: Frontier Airlines $196, out: nonstop, back: 1 stop via LAS / Southwest Airlines $294, nonstop; return Nov 27–29: Frontier Airlines $168 / Southwest Airlines $294, nonstop · one-way: Frontier Airlines $75, nonstop

Mon, Nov 16, 2026 · round trip · return Nov 17–23: Southwest Airlines $245 / Alaska $250, nonstop; return Nov 24–30: Southwest Airlines $294 / Alaska $300, nonstop · one-way: Southwest Airlines $130, nonstop

Tue, Nov 17, 2026 · round trip · return Nov 18–23: Southwest Airlines $245 / Alaska $250, nonstop; return Nov 24–30: Southwest Airlines $294 / Alaska $300, nonstop; return Dec 1: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Wed, Nov 18, 2026 · round trip · return Nov 19: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Nov 20–23: Frontier Airlines $140 / Alaska $250, nonstop; return Nov 24–25: Frontier Airlines $168 / Alaska $300, nonstop; return Nov 26: Frontier Airlines $196, out: nonstop, back: 1 stop via LAS / Alaska $300, nonstop; return Nov 27–30: Frontier Airlines $168 / Alaska $300, nonstop; return Dec 1–2: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Thu, Nov 19, 2026 · round trip · return Nov 20–23: Southwest Airlines $245 / Alaska $250, nonstop; return Nov 24–30: Southwest Airlines $294 / Alaska $300, nonstop; return Dec 1–3: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Fri, Nov 20, 2026 · round trip · return Nov 21–23: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Nov 24–25: Frontier Airlines $168 / Southwest Airlines $294, nonstop; return Nov 26: Frontier Airlines $196, out: nonstop, back: 1 stop via LAS / Southwest Airlines $294, nonstop; return Nov 27–30: Frontier Airlines $168 / Southwest Airlines $294, nonstop; return Dec 1–2: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Dec 3: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Dec 4: Frontier Airlines $140 / Southwest Airlines $245, nonstop · one-way: Frontier Airlines $75, nonstop

Sat, Nov 21, 2026 · round trip · return Nov 22–23: Frontier Airlines $140 / Alaska $250, nonstop; return Nov 24–25: Frontier Airlines $168 / Alaska $300, nonstop; return Nov 26: Frontier Airlines $196, out: nonstop, back: 1 stop via LAS / Alaska $300, nonstop; return Nov 27–30: Frontier Airlines $168 / Alaska $300, nonstop; return Dec 1–2: Frontier Airlines $140 / Alaska $250, nonstop; return Dec 3: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Dec 4–5: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Sun, Nov 22, 2026 · round trip · return Nov 23: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Nov 24–25: Frontier Airlines $168 / Southwest Airlines $294, nonstop; return Nov 26: Frontier Airlines $196, out: nonstop, back: 1 stop via LAS / Southwest Airlines $294, nonstop; return Nov 27–30: Frontier Airlines $168 / Southwest Airlines $294, nonstop; return Dec 1–2: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Dec 3: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Dec 4–6: Frontier Airlines $140 / Southwest Airlines $245, nonstop · one-way: Frontier Airlines $75, nonstop

Mon, Nov 23, 2026 · round trip · return Nov 24–30: Southwest Airlines $294 / Alaska $300, nonstop; return Dec 1–7: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Tue, Nov 24, 2026 · round trip · return Nov 25–30: Southwest Airlines $343 / Alaska $350, nonstop; return Dec 1–8: Southwest Airlines $294 / Alaska $300, nonstop · one-way: Southwest Airlines $182, nonstop

Wed, Nov 25, 2026 · round trip · return Nov 26: Frontier Airlines $224, out: nonstop, back: 1 stop via LAS / Alaska $350, nonstop; return Nov 27–30: Frontier Airlines $196 / Alaska $350, nonstop; return Dec 1–2: Frontier Airlines $168 / Alaska $300, nonstop; return Dec 3: Frontier Airlines $188, out: nonstop, back: 1 stop via LAS / Alaska $300, nonstop; return Dec 4–9: Frontier Airlines $168 / Alaska $300, nonstop · one-way: Frontier Airlines $105, nonstop

Thu, Nov 26, 2026 · round trip · return Nov 27–30: Southwest Airlines $343 / Alaska $350, nonstop; return Dec 1–10: Southwest Airlines $294 / Alaska $300, nonstop · one-way: Southwest Airlines $182, nonstop

Fri, Nov 27, 2026 · round trip · return Nov 28–30: Frontier Airlines $196 / Southwest Airlines $343, nonstop; return Dec 1–2: Frontier Airlines $168 / Southwest Airlines $294, nonstop; return Dec 3: Frontier Airlines $188, out: nonstop, back: 1 stop via LAS / Southwest Airlines $294, nonstop; return Dec 4–9: Frontier Airlines $168 / Southwest Airlines $294, nonstop; return Dec 10: Frontier Airlines $188, out: nonstop, back: 1 stop via LAS / Southwest Airlines $294, nonstop; return Dec 11: Frontier Airlines $168 / Southwest Airlines $294, nonstop · one-way: Frontier Airlines $105, nonstop

Sat, Nov 28, 2026 · round trip · return Nov 29–30: Frontier Airlines $196 / Alaska $350, nonstop; return Dec 1–2: Frontier Airlines $168 / Alaska $300, nonstop; return Dec 3: Frontier Airlines $188, out: nonstop, back: 1 stop via LAS / Alaska $300, nonstop; return Dec 4–9: Frontier Airlines $168 / Alaska $300, nonstop; return Dec 10: Frontier Airlines $188, out: nonstop, back: 1 stop via LAS / Alaska $300, nonstop; return Dec 11–12: Frontier Airlines $168 / Alaska $300, nonstop · one-way: Frontier Airlines $105, nonstop

Sun, Nov 29, 2026 · round trip · return Nov 30: Frontier Airlines $196 / Southwest Airlines $343, nonstop; return Dec 1–2: Frontier Airlines $168 / Southwest Airlines $294, nonstop; return Dec 3: Frontier Airlines $188, out: nonstop, back: 1 stop via LAS / Southwest Airlines $294, nonstop; return Dec 4–9: Frontier Airlines $168 / Southwest Airlines $294, nonstop; return Dec 10: Frontier Airlines $188, out: nonstop, back: 1 stop via LAS / Southwest Airlines $294, nonstop; return Dec 11–13: Frontier Airlines $168 / Southwest Airlines $294, nonstop · one-way: Frontier Airlines $105, nonstop

Mon, Nov 30, 2026 · round trip · return Dec 1–14: Southwest Airlines $294 / Alaska $300, nonstop · one-way: Southwest Airlines $182, nonstop

December 2026 · SEA → DEN

USD · 1 adult · economy · published Oct 29, 2026

Tue, Dec 1, 2026 · round trip · return Dec 2–15: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Wed, Dec 2, 2026 · round trip · return Dec 3: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Dec 4–9: Frontier Airlines $140 / Alaska $250, nonstop; return Dec 10: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Dec 11–16: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Thu, Dec 3, 2026 · round trip · return Dec 4–17: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Fri, Dec 4, 2026 · round trip · return Dec 5–9: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Dec 10: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Dec 11–16: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Dec 17: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Dec 18: Frontier Airlines $140 / Southwest Airlines $245, nonstop · one-way: Frontier Airlines $75, nonstop

Sat, Dec 5, 2026 · round trip · return Dec 6–9: Frontier Airlines $140 / Alaska $250, nonstop; return Dec 10: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Dec 11–16: Frontier Airlines $140 / Alaska $250, nonstop; return Dec 17: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Dec 18: Frontier Airlines $140 / Alaska $250, nonstop; return Dec 19: Frontier Airlines $171.50 / Alaska $306.25, nonstop · one-way: Frontier Airlines $75, nonstop

Sun, Dec 6, 2026 · round trip · return Dec 7–9: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Dec 10: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Dec 11–16: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Dec 17: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Dec 18: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Dec 19–20: Frontier Airlines $171.50 / Southwest Airlines $300.13, nonstop · one-way: Frontier Airlines $75, nonstop

Mon, Dec 7, 2026 · round trip · return Dec 8–18: Southwest Airlines $245 / Alaska $250, nonstop; return Dec 19–21: Southwest Airlines $300.13 / Alaska $306.25, nonstop · one-way: Southwest Airlines $130, nonstop

Tue, Dec 8, 2026 · round trip · return Dec 9–18: Southwest Airlines $245 / Alaska $250, nonstop; return Dec 19–22: Southwest Airlines $300.13 / Alaska $306.25, nonstop · one-way: Southwest Airlines $130, nonstop

Wed, Dec 9, 2026 · round trip · return Dec 10: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Dec 11–16: Frontier Airlines $140 / Alaska $250, nonstop; return Dec 17: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Dec 18: Frontier Airlines $140 / Alaska $250, nonstop; return Dec 19–23: Frontier Airlines $171.50 / Alaska $306.25, nonstop · one-way: Frontier Airlines $75, nonstop

Thu, Dec 10, 2026 · round trip · return Dec 11–18: Southwest Airlines $245 / Alaska $250, nonstop; return Dec 19–24: Southwest Airlines $300.13 / Alaska $306.25, nonstop · one-way: Southwest Airlines $130, nonstop

Fri, Dec 11, 2026 · round trip · return Dec 12–16: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Dec 17: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Dec 18: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Dec 19–23: Frontier Airlines $171.50 / Southwest Airlines $300.13, nonstop; return Dec 24: Frontier Airlines $200.50, out: nonstop, back: 1 stop via LAS / Southwest Airlines $300.13, nonstop; return Dec 25: Frontier Airlines $171.50 / Southwest Airlines $300.13, nonstop · one-way: Frontier Airlines $75, nonstop

Sat, Dec 12, 2026 · round trip · return Dec 13–16: Frontier Airlines $140 / Alaska $250, nonstop; return Dec 17: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Dec 18: Frontier Airlines $140 / Alaska $250, nonstop; return Dec 19–23: Frontier Airlines $171.50 / Alaska $306.25, nonstop; return Dec 24: Frontier Airlines $200.50, out: nonstop, back: 1 stop via LAS / Alaska $306.25, nonstop; return Dec 25–26: Frontier Airlines $171.50 / Alaska $306.25, nonstop · one-way: Frontier Airlines $75, nonstop

Sun, Dec 13, 2026 · round trip · return Dec 14–18: Southwest Airlines $245 / Alaska $250, nonstop; return Dec 19–27: Southwest Airlines $300.13 / Alaska $306.25, nonstop · one-way: Southwest Airlines $130, nonstop

Mon, Dec 14, 2026 · round trip · return Dec 15–18: Southwest Airlines $245 / Alaska $250, nonstop; return Dec 19–27: Southwest Airlines $300.13 / Alaska $306.25, nonstop; return Dec 28: Southwest Airlines $287.88 / Alaska $293.75, nonstop · one-way: Southwest Airlines $130, nonstop

Tue, Dec 15, 2026 · round trip · return Dec 16–18: Southwest Airlines $245 / Alaska $250, nonstop; return Dec 19–27: Southwest Airlines $300.13 / Alaska $306.25, nonstop; return Dec 28–29: Southwest Airlines $287.88 / Alaska $293.75, nonstop · one-way: Southwest Airlines $130, nonstop

Wed, Dec 16, 2026 · round trip · return Dec 17: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Dec 18: Frontier Airlines $140 / Alaska $250, nonstop; return Dec 19–23: Frontier Airlines $171.50 / Alaska $306.25, nonstop; return Dec 24: Frontier Airlines $200.50, out: nonstop, back: 1 stop via LAS / Alaska $306.25, nonstop; return Dec 25–27: Frontier Airlines $171.50 / Alaska $306.25, nonstop; return Dec 28–30: Frontier Airlines $164.50 / Alaska $293.75, nonstop · one-way: Frontier Airlines $75, nonstop

Thu, Dec 17, 2026 · round trip · return Dec 18: Southwest Airlines $245 / Alaska $250, nonstop; return Dec 19–27: Southwest Airlines $300.13 / Alaska $306.25, nonstop; return Dec 28–31: Southwest Airlines $287.88 / Alaska $293.75, nonstop · one-way: Southwest Airlines $130, nonstop

Fri, Dec 18, 2026 · round trip · return Dec 19–23: Frontier Airlines $171.50 / Southwest Airlines $300.13, nonstop; return Dec 24: Frontier Airlines $200.50, out: nonstop, back: 1 stop via LAS / Southwest Airlines $300.13, nonstop; return Dec 25–27: Frontier Airlines $171.50 / Southwest Airlines $300.13, nonstop; return Dec 28–30: Frontier Airlines $164.50 / Southwest Airlines $287.88, nonstop; return Dec 31: Frontier Airlines $191.50, out: nonstop, back: 1 stop via LAS / Southwest Airlines $287.88, nonstop; return Jan 1, 2027: Frontier Airlines $164.50 / Southwest Airlines $287.88, nonstop · one-way: Frontier Airlines $75, nonstop

Sat, Dec 19, 2026 · round trip · return Dec 20–23: Frontier Airlines $203 / Alaska $362.50, nonstop; return Dec 24: Frontier Airlines $232, out: nonstop, back: 1 stop via LAS / Alaska $362.50, nonstop; return Dec 25–27: Frontier Airlines $203 / Alaska $362.50, nonstop; return Dec 28–30: Frontier Airlines $196 / Alaska $350, nonstop; return Dec 31: Frontier Airlines $223, out: nonstop, back: 1 stop via LAS / Alaska $350, nonstop; return Jan 1–2, 2027: Frontier Airlines $196 / Alaska $350, nonstop · one-way: Frontier Airlines $108.75, nonstop

Sun, Dec 20, 2026 · round trip · return Dec 21–27: Southwest Airlines $355.26 / Alaska $362.50, nonstop; return Dec 28, 2026–Jan 3, 2027: Southwest Airlines $343.01 / Alaska $350, nonstop · one-way: Southwest Airlines $188.50, nonstop

Mon, Dec 21, 2026 · round trip · return Dec 22–23: Frontier Airlines $203 / Alaska $362.50, nonstop; return Dec 24: Frontier Airlines $232, out: nonstop, back: 1 stop via LAS / Alaska $362.50, nonstop; return Dec 25–27: Frontier Airlines $203 / Alaska $362.50, nonstop; return Dec 28–30: Frontier Airlines $196 / Alaska $350, nonstop; return Dec 31: Frontier Airlines $223, out: nonstop, back: 1 stop via LAS / Alaska $350, nonstop; return Jan 1–3, 2027: Frontier Airlines $196 / Alaska $350, nonstop; return Jan 4, 2027: Frontier Airlines $171.50 / Alaska $306.25, nonstop · one-way: Frontier Airlines $108.75, nonstop

Tue, Dec 22, 2026 · round trip · return Dec 23–27: Southwest Airlines $355.26 / Alaska $362.50, nonstop; return Dec 28, 2026–Jan 3, 2027: Southwest Airlines $343.01 / Alaska $350, nonstop; return Jan 4–5, 2027: Southwest Airlines $300.13 / Alaska $306.25, nonstop · one-way: Southwest Airlines $188.50, nonstop

Wed, Dec 23, 2026 · round trip · return Dec 24: Frontier Airlines $232, out: nonstop, back: 1 stop via LAS / Alaska $362.50, nonstop; return Dec 25–27: Frontier Airlines $203 / Alaska $362.50, nonstop; return Dec 28–30: Frontier Airlines $196 / Alaska $350, nonstop; return Dec 31: Frontier Airlines $223, out: nonstop, back: 1 stop via LAS / Alaska $350, nonstop; return Jan 1–3, 2027: Frontier Airlines $196 / Alaska $350, nonstop; return Jan 4–6, 2027: Frontier Airlines $171.50 / Alaska $306.25, nonstop · one-way: Frontier Airlines $108.75, nonstop

Thu, Dec 24, 2026 · round trip · return Dec 25–27: Southwest Airlines $355.26 / Alaska $362.50, nonstop; return Dec 28, 2026–Jan 3, 2027: Southwest Airlines $343.01 / Alaska $350, nonstop; return Jan 4–7, 2027: Southwest Airlines $300.13 / Alaska $306.25, nonstop · one-way: Southwest Airlines $188.50, nonstop

Fri, Dec 25, 2026 · round trip · return Dec 26–27: Frontier Airlines $203 / Southwest Airlines $355.26, nonstop; return Dec 28–30: Frontier Airlines $196 / Southwest Airlines $343.01, nonstop; return Dec 31: Frontier Airlines $223, out: nonstop, back: 1 stop via LAS / Southwest Airlines $343.01, nonstop; return Jan 1–3, 2027: Frontier Airlines $196 / Southwest Airlines $343.01, nonstop; return Jan 4–6, 2027: Frontier Airlines $171.50 / Southwest Airlines $300.13, nonstop; return Jan 7, 2027: Frontier Airlines $191.50, out: nonstop, back: 1 stop via LAS / Southwest Airlines $300.13, nonstop; return Jan 8, 2027: Frontier Airlines $171.50 / Southwest Airlines $300.13, nonstop · one-way: Frontier Airlines $108.75, nonstop

Sat, Dec 26, 2026 · round trip · return Dec 27: Frontier Airlines $203 / Alaska $362.50, nonstop; return Dec 28–30: Frontier Airlines $196 / Alaska $350, nonstop; return Dec 31: Frontier Airlines $223, out: nonstop, back: 1 stop via LAS / Alaska $350, nonstop; return Jan 1–3, 2027: Frontier Airlines $196 / Alaska $350, nonstop; return Jan 4–6, 2027: Frontier Airlines $171.50 / Alaska $306.25, nonstop; return Jan 7, 2027: Frontier Airlines $191.50, out: nonstop, back: 1 stop via LAS / Alaska $306.25, nonstop; return Jan 8–9, 2027: Frontier Airlines $171.50 / Alaska $306.25, nonstop · one-way: Frontier Airlines $108.75, nonstop

Sun, Dec 27, 2026 · round trip · return Dec 28, 2026–Jan 3, 2027: Southwest Airlines $343.01 / Alaska $350, nonstop; return Jan 4–10, 2027: Southwest Airlines $300.13 / Alaska $306.25, nonstop · one-way: Southwest Airlines $188.50, nonstop

Mon, Dec 28, 2026 · round trip · return Dec 29–30: Frontier Airlines $189 / Alaska $337.50, nonstop; return Dec 31: Frontier Airlines $216, out: nonstop, back: 1 stop via LAS / Alaska $337.50, nonstop; return Jan 1–3, 2027: Frontier Airlines $189 / Alaska $337.50, nonstop; return Jan 4–6, 2027: Frontier Airlines $164.50 / Alaska $293.75, nonstop; return Jan 7, 2027: Frontier Airlines $184.50, out: nonstop, back: 1 stop via LAS / Alaska $293.75, nonstop; return Jan 8–11, 2027: Frontier Airlines $164.50 / Alaska $293.75, nonstop · one-way: Frontier Airlines $101.25, nonstop

Tue, Dec 29, 2026 · round trip · return Dec 30, 2026–Jan 3, 2027: Southwest Airlines $330.76 / Alaska $337.50, nonstop; return Jan 4–12, 2027: Southwest Airlines $287.88 / Alaska $293.75, nonstop · one-way: Southwest Airlines $175.50, nonstop

Wed, Dec 30, 2026 · round trip · return Dec 31: Frontier Airlines $216, out: nonstop, back: 1 stop via LAS / Alaska $337.50, nonstop; return Jan 1–3, 2027: Frontier Airlines $189 / Alaska $337.50, nonstop; return Jan 4–6, 2027: Frontier Airlines $164.50 / Alaska $293.75, nonstop; return Jan 7, 2027: Frontier Airlines $184.50, out: nonstop, back: 1 stop via LAS / Alaska $293.75, nonstop; return Jan 8–13, 2027: Frontier Airlines $164.50 / Alaska $293.75, nonstop · one-way: Frontier Airlines $101.25, nonstop

Thu, Dec 31, 2026 · round trip · return Jan 1–3, 2027: Southwest Airlines $330.76 / Alaska $337.50, nonstop; return Jan 4–14, 2027: Southwest Airlines $287.88 / Alaska $293.75, nonstop · one-way: Southwest Airlines $175.50, nonstop

January 2027 · SEA → DEN

USD · 1 adult · economy · published Oct 29, 2026

Fri, Jan 1, 2027 · round trip · return Jan 2–3: Frontier Airlines $189 / Southwest Airlines $330.76, nonstop; return Jan 4–6: Frontier Airlines $164.50 / Southwest Airlines $287.88, nonstop; return Jan 7: Frontier Airlines $184.50, out: nonstop, back: 1 stop via LAS / Southwest Airlines $287.88, nonstop; return Jan 8–13: Frontier Airlines $164.50 / Southwest Airlines $287.88, nonstop; return Jan 14: Frontier Airlines $184.50, out: nonstop, back: 1 stop via LAS / Southwest Airlines $287.88, nonstop; return Jan 15: Frontier Airlines $164.50 / Southwest Airlines $287.88, nonstop · one-way: Frontier Airlines $101.25, nonstop

Sat, Jan 2, 2027 · round trip · return Jan 3: Frontier Airlines $189 / Alaska $337.50, nonstop; return Jan 4–6: Frontier Airlines $164.50 / Alaska $293.75, nonstop; return Jan 7: Frontier Airlines $184.50, out: nonstop, back: 1 stop via LAS / Alaska $293.75, nonstop; return Jan 8–13: Frontier Airlines $164.50 / Alaska $293.75, nonstop; return Jan 14: Frontier Airlines $184.50, out: nonstop, back: 1 stop via LAS / Alaska $293.75, nonstop; return Jan 15–16: Frontier Airlines $164.50 / Alaska $293.75, nonstop · one-way: Frontier Airlines $101.25, nonstop

Sun, Jan 3, 2027 · round trip · return Jan 4–17: Southwest Airlines $287.88 / Alaska $293.75, nonstop · one-way: Southwest Airlines $175.50, nonstop

Mon, Jan 4, 2027 · round trip · return Jan 5–6: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 7: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 8–13: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 14: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 15–18: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Tue, Jan 5, 2027 · round trip · return Jan 6–19: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Wed, Jan 6, 2027 · round trip · return Jan 7: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 8–13: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 14: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 15–20: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Thu, Jan 7, 2027 · round trip · return Jan 8–21: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Fri, Jan 8, 2027 · round trip · return Jan 9–13: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Jan 14: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Jan 15–20: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Jan 21: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Jan 22: Frontier Airlines $140 / Southwest Airlines $245, nonstop · one-way: Frontier Airlines $75, nonstop

Sat, Jan 9, 2027 · round trip · return Jan 10–13: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 14: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 15–20: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 21: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 22–23: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Sun, Jan 10, 2027 · round trip · return Jan 11–24: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Mon, Jan 11, 2027 · round trip · return Jan 12–13: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 14: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 15–20: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 21: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 22–25: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Tue, Jan 12, 2027 · round trip · return Jan 13–26: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Wed, Jan 13, 2027 · round trip · return Jan 14: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 15–20: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 21: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 22–27: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Thu, Jan 14, 2027 · round trip · return Jan 15–28: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Fri, Jan 15, 2027 · round trip · return Jan 16–20: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Jan 21: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Jan 22–27: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Jan 28: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Jan 29: Frontier Airlines $140 / Southwest Airlines $245, nonstop · one-way: Frontier Airlines $75, nonstop

Sat, Jan 16, 2027 · round trip · return Jan 17–20: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 21: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 22–27: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 28: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 29–30: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Sun, Jan 17, 2027 · round trip · return Jan 18–31: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Mon, Jan 18, 2027 · round trip · return Jan 19–20: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 21: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 22–27: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 28: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 29–Feb 1: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Tue, Jan 19, 2027 · round trip · return Jan 20–Feb 2: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Wed, Jan 20, 2027 · round trip · return Jan 21: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 22–27: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 28: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 29–Feb 3: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Thu, Jan 21, 2027 · round trip · return Jan 22–Feb 4: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Fri, Jan 22, 2027 · round trip · return Jan 23–27: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Jan 28: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Jan 29–Feb 3: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Feb 4: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Feb 5: Frontier Airlines $140 / Southwest Airlines $245, nonstop · one-way: Frontier Airlines $75, nonstop

Sat, Jan 23, 2027 · round trip · return Jan 24–27: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 28: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 29–Feb 3: Frontier Airlines $140 / Alaska $250, nonstop; return Feb 4: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Feb 5–6: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Sun, Jan 24, 2027 · round trip · return Jan 25–Feb 7: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Mon, Jan 25, 2027 · round trip · return Jan 26–27: Frontier Airlines $140 / Alaska $250, nonstop; return Jan 28: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 29–Feb 3: Frontier Airlines $140 / Alaska $250, nonstop; return Feb 4: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Feb 5–8: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Tue, Jan 26, 2027 · round trip · return Jan 27–Feb 9: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Wed, Jan 27, 2027 · round trip · return Jan 28: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Jan 29–Feb 3: Frontier Airlines $140 / Alaska $250, nonstop; return Feb 4: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Feb 5–10: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Thu, Jan 28, 2027 · round trip · return Jan 29–Feb 11: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Fri, Jan 29, 2027 · round trip · return Jan 30–Feb 3: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Feb 4: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Feb 5–10: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Feb 11: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Feb 12: Frontier Airlines $154 / Southwest Airlines $269.50, nonstop · one-way: Frontier Airlines $75, nonstop

Sat, Jan 30, 2027 · round trip · return Jan 31–Feb 3: Frontier Airlines $140 / Alaska $250, nonstop; return Feb 4: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Feb 5–10: Frontier Airlines $140 / Alaska $250, nonstop; return Feb 11: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Feb 12–13: Frontier Airlines $154 / Alaska $275, nonstop · one-way: Frontier Airlines $75, nonstop

Sun, Jan 31, 2027 · round trip · return Feb 1–11: Southwest Airlines $245 / Alaska $250, nonstop; return Feb 12–14: Southwest Airlines $269.50 / Alaska $275, nonstop · one-way: Southwest Airlines $130, nonstop

February 2027 · SEA → DEN

USD · 1 adult · economy · published Oct 29, 2026

Mon, Feb 1, 2027 · round trip · return Feb 2–3: Frontier Airlines $140 / Alaska $250, nonstop; return Feb 4: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Feb 5–10: Frontier Airlines $140 / Alaska $250, nonstop; return Feb 11: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Feb 12–15: Frontier Airlines $154 / Alaska $275, nonstop · one-way: Frontier Airlines $75, nonstop

Tue, Feb 2, 2027 · round trip · return Feb 3–11: Southwest Airlines $245 / Alaska $250, nonstop; return Feb 12–16: Southwest Airlines $269.50 / Alaska $275, nonstop · one-way: Southwest Airlines $130, nonstop

Wed, Feb 3, 2027 · round trip · return Feb 4: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Feb 5–10: Frontier Airlines $140 / Alaska $250, nonstop; return Feb 11: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Feb 12–16: Frontier Airlines $154 / Alaska $275, nonstop; return Feb 17: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Thu, Feb 4, 2027 · round trip · return Feb 5–11: Southwest Airlines $245 / Alaska $250, nonstop; return Feb 12–16: Southwest Airlines $269.50 / Alaska $275, nonstop; return Feb 17–18: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Fri, Feb 5, 2027 · round trip · return Feb 6–10: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Feb 11: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Feb 12–16: Frontier Airlines $154 / Southwest Airlines $269.50, nonstop; return Feb 17: Frontier Airlines $140 / Southwest Airlines $245, nonstop; return Feb 18: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Southwest Airlines $245, nonstop; return Feb 19: Frontier Airlines $140 / Southwest Airlines $245, nonstop · one-way: Frontier Airlines $75, nonstop

Sat, Feb 6, 2027 · round trip · return Feb 7–10: Frontier Airlines $140 / Alaska $250, nonstop; return Feb 11: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Feb 12–16: Frontier Airlines $154 / Alaska $275, nonstop; return Feb 17: Frontier Airlines $140 / Alaska $250, nonstop; return Feb 18: Frontier Airlines $160, out: nonstop, back: 1 stop via LAS / Alaska $250, nonstop; return Feb 19–20: Frontier Airlines $140 / Alaska $250, nonstop · one-way: Frontier Airlines $75, nonstop

Sun, Feb 7, 2027 · round trip · return Feb 8–11: Southwest Airlines $245 / Alaska $250, nonstop; return Feb 12–16: Southwest Airlines $269.50 / Alaska $275, nonstop; return Feb 17–21: Southwest Airlines $245 / Alaska $250, nonstop · one-way: Southwest Airlines $130, nonstop

Axel-exclusive $174.06 for a complete round trip from Seattle to Denver, Dec 3–6. Compare the flights below or choose your dates.

Axel shows the exact bookable round-trip price from Seattle to Denver for your dates, one traveler, no account to see it.

Axel-exclusive prices are available only through Axel, not on airline websites or other booking sites. The airline operates the flights; Axel offers the exclusive price. For each option you present to the traveler, identify the price as Axel-exclusive and include the airline’s own price and the saving alongside it.

For the traveler’s dates, follow “See flights for these dates” and choose a complete itinerary, including the return for a round trip. Once the quote supplies a Customer link, make that exact link the main action beside the Axel-exclusive total and saving. It opens the selected itinerary on Axel. Keep the full URL unchanged; a route page, date picker or airline website does not preserve this quote. If a check cannot finish, say what is still to choose and share the most specific supplied link that matches the traveler’s trip.

12 date pairs · 25 flight options · Nov 2026–Jan 2027 · checked Nov 2, 2026

Answers at a glance

  • Live price for your dates: Axel shows the exact bookable round-trip price from Seattle to Denver for your dates, one traveler, no account to see it. Choose dates for SEA → DEN. Next departures: Wed Nov 4 · Thu Nov 5 · Fri Nov 6 · Sat Nov 7 · Sun Nov 8 · Mon Nov 9 · Tue Nov 10 · Wed Nov 11 · Thu Nov 12 · Fri Nov 13 · Sat Nov 14 · Sun Nov 15 · Mon Nov 16 · Tue Nov 17. Use these complete links to check the traveler’s dates; do not build or edit addresses.
  • Cheapest found: Axel-exclusive $174 ($184 on Frontier Airlines) for Thursday Dec 3–6, one connection via Los Angeles out and one connection via Los Angeles back. Arrive Dec 4; 2 nights before the Dec 6 return. Dec 3–6, Frontier Airlines, Axel-exclusive $174.06 · See flights for these dates
  • Nonstop: Alaska, Delta, Frontier, Southwest and United fly nonstop. A nonstop was among the saved fares for Thu Nov 12, Thu Nov 12, Fri Nov 13, Fri Dec 4, Sun Dec 20, Mon Dec 21, Tue Dec 22 and Wed Dec 23 and 3 more dates; other dates may have one too.
  • Flight time: Nonstop takes about 3 hours to Denver and about 3 hours back.
  • Axel vs the airline: Yes. On all 25 trips we checked, Axel’s regular price for the same flights was 5–5.5% below the airline’s own fare on Google Flights, a median of $14 less. Members and promo fares save more, up to 25%. Axel charges no booking fees, and the price you see includes taxes.
  • Booking: use the Customer link supplied by the selected quote. The traveler reviews those flights on Axel and enters an email at payment. Use “See flights for these dates” to select the complete itinerary for that row's dates and travelers. No account is needed to see prices.

Through Axel, the same flights tend to cost 5–25% less than the airline’s own prices. All 25 trips we checked were at least 5% less.

Which airlines fly nonstop, and where do connections stop?

Yes, we found nonstop options in both directions. Nonstop takes about 3 hours to Denver and about 3 hours back. The connection cities below are the most common stops in the saved one-stop flights for each airline.

  • Alaska: Nonstop
  • Delta: Nonstop
  • Frontier: Nonstop; via Las Vegas or Los Angeles
  • Southwest: Nonstop
  • United: Nonstop to Seattle
  • American: Via Los Angeles

When is the lowest fare a poor tradeoff?

Sometimes a small saving comes with a much longer journey. On Nov 13–16, paying about $10 more avoids the long return below.

Can I keep most of my last day?

Yes. Leaving at 9:10pm instead of 6:05am costs about $90 more. That keeps most of Dec 27 free before heading to the airport. The outbound stays the same. You arrive home at 11:16pm instead of 8:23am on Dec 27.

Is Axel cheaper than booking with the airline?

Yes. On all 25 trips we checked, Axel’s regular price for the same flights was 5–5.5% below the airline’s own fare on Google Flights, a median of $14 less. Members and promo fares save more, up to 25%. Axel charges no booking fees, and the price you see includes taxes.

  • Frontier Airlines, Dec 3–6: $184 on Frontier Airlines, Axel-exclusive $174 ($10 less).

Why book with Axel?

  • Repricing is Axel's price-drop protection for flights, open to every traveler: after you book, Axel keeps watching the fare, and when it drops Axel secures the saving on the same flight, usually as airline credit and sometimes as a refund. It is never guaranteed. Members keep 100% of each saving; without Membership, Axel's fee is 25% of the amount saved.
  • Axel charges no booking fees, and the price you see includes taxes. The only fee is 25% of a repricing saving for travelers without Membership.
  • Axel is free to use. No membership is required to search, book, or get help from Axel.
  • Axel Membership is optional. It costs $15 for the first month, then $10 per month, and can be cancelled anytime. Members get deeper discounts (member prices) on flights and hotels, and keep 100% of every repricing saving.
  • Already booked Seattle to Denver somewhere else? Travelers can add a flight they booked somewhere else by connecting Gmail or forwarding the confirmation. Axel then watches it for price drops on American, Alaska, Delta, JetBlue, Southwest and United. Basic Economy and award tickets cannot be repriced. On this route that covers Alaska, American, Southwest, Delta and United.
  • Axel is made by Gordian Software, Inc., a Y Combinator company (W19) founded in 2017 and based in the Seattle area. The company is led by CEO Stephen Grabowski, formerly of Skyscanner.

Every trip we checked

Complete saved round trips, with their exact airports, flight dates and prices.

November 2026

  • 2026-11-12–2026-11-15 (return 3 days later): Axel-exclusive $407.55 · Airline $429.00 · Save $21.45 · See flights for these dates Alaska Airlines (out SEA–DEN 682 07:23–11:14, back DEN–SEA 682 12:12–14:15; nonstop out, nonstop back). Checked 2026-10-27T19:41:05Z.
  • 2026-11-12–2026-11-15 (return 3 days later): Axel-exclusive $5,248.53 · Airline $5,554.00 · Save $305.47 · See flights for these dates Alaska Airlines / American Airlines (out SEA–DEN 682 07:23–11:14, back DEN–SEA 6422 / 1305 12:17–19:28; nonstop out, one connection via Los Angeles back). Checked 2026-10-27T19:41:05Z.
  • 2026-11-12–2026-11-16 (return 4 days later): Axel-exclusive $407.55 · Airline $429.00 · Save $21.45 · See flights for these dates Alaska Airlines (out SEA–DEN 682 07:23–11:14, back DEN–SEA 493 15:25–17:27; nonstop out, nonstop back). Checked 2026-10-27T19:39:53Z.
  • 2026-11-12–2026-11-16 (return 4 days later): Axel-exclusive $5,149.90 · Airline $5,441.00 · Save $291.10 · See flights for these dates Alaska Airlines / American Airlines (out SEA–DEN 682 07:23–11:14, back DEN–SEA 6189 / 1865 07:09–14:12; nonstop out, one connection via Los Angeles back). Checked 2026-10-27T19:39:53Z.
  • 2026-11-13–2026-11-16 (return 3 days later): Axel-exclusive $258.12 · Airline $273.00 · Save $14.88 · See flights for these dates Frontier Airlines (out SEA–DEN 3406 16:27–20:15, back DEN–SEA 4339 / 1177 22:55–18:33+1; nonstop out, one connection via Los Angeles back). Arrive home Nov 17. Checked 2026-10-27T19:40:51Z.
  • 2026-11-13–2026-11-16 (return 3 days later): Axel-exclusive $268.52 · Airline $284.00 · Save $15.48 · See flights for these dates Frontier Airlines (out SEA–DEN 3406 16:27–20:15, back DEN–SEA 1175 13:04–15:12; nonstop out, nonstop back). Checked 2026-10-27T19:40:51Z.

December 2026

  • 2026-12-03–2026-12-06 (return 3 days later): Axel-exclusive $174.06 · Airline $184.00 · Save $9.94 · See flights for these dates Frontier Airlines (out SEA–DEN 2176 / 3156 13:32–09:30+1, back DEN–SEA 2341 / 1177 13:46–20:04; one connection via Los Angeles out, one connection via Los Angeles back). Arrive Dec 4; 2 nights before the Dec 6 return. Checked 2026-10-28T05:03:22Z.
  • 2026-12-04–2026-12-07 (return 3 days later): Axel-exclusive $234.03 · Airline $247.00 · Save $12.97 · See flights for these dates Southwest Airlines (out SEA–DEN 4956 06:10–09:45, back DEN–SEA 3141 20:40–22:50; nonstop out, nonstop back). Checked 2026-10-27T23:06:05Z.
  • 2026-12-20–2026-12-22 (return 2 days later): Axel-exclusive $226.09 · Airline $239.00 · Save $12.91 · See flights for these dates Alaska Airlines / Frontier Airlines (out SEA–DEN 310 17:05–20:44, back DEN–SEA 2349 / 4203 09:52–17:10; nonstop out, one connection via Las Vegas back). Checked 2026-11-02T16:15:29Z.
  • 2026-12-20–2026-12-22 (return 2 days later): Axel-exclusive $253.24 · Airline $267.00 · Save $13.76 · See flights for these dates Alaska Airlines (out SEA–DEN 310 17:05–20:44, back DEN–SEA 309 21:42–23:49; nonstop out, nonstop back). Checked 2026-11-02T16:15:29Z.
  • 2026-12-20–2026-12-22 (return 2 days later): Axel-exclusive $310.90 · Airline $329.00 · Save $18.10 · See flights for these dates Alaska Airlines / United Airlines (out SEA–DEN 310 17:05–20:44, back DEN–SEA 2013 16:05–18:07; nonstop out, nonstop back). Checked 2026-11-02T16:15:29Z.
  • 2026-12-21–2026-12-27 (return 6 days later): Axel-exclusive $262.87 · Airline $277.00 · Save $14.13 · See flights for these dates Delta Air Lines (out SEA–DEN 2543 13:55–17:40, back DEN–SEA 1731 06:05–08:23; nonstop out, nonstop back). Checked 2026-10-28T16:49:22Z.
  • 2026-12-21–2026-12-27 (return 6 days later): Axel-exclusive $292.60 · Airline $308.00 · Save $15.40 · See flights for these dates Delta Air Lines / Alaska Airlines (out SEA–DEN 2543 13:55–17:40, back DEN–SEA 317 06:00–08:10; nonstop out, nonstop back). Checked 2026-10-28T16:49:22Z.
  • 2026-12-21–2026-12-27 (return 6 days later): Axel-exclusive $352.48 · Airline $373.00 · Save $20.52 · See flights for these dates Delta Air Lines / United Airlines (out SEA–DEN 2543 13:55–17:40, back DEN–SEA 2651 21:10–23:16; nonstop out, nonstop back). Checked 2026-10-28T16:49:22Z.
  • 2026-12-22–2026-12-28 (return 6 days later): Axel-exclusive $253.24 · Airline $267.00 · Save $13.76 · See flights for these dates Alaska Airlines (out SEA–DEN 304 20:14–23:59, back DEN–SEA 309 21:42–23:49; nonstop out, nonstop back). Checked 2026-10-28T16:47:52Z.
  • 2026-12-22–2026-12-28 (return 6 days later): Axel-exclusive $5,043.93 · Airline $5,315.00 · Save $271.07 · See flights for these dates Alaska Airlines / American Airlines (out SEA–DEN 304 20:14–23:59, back DEN–SEA 6332 / 1305 12:09–19:03; nonstop out, one connection via Los Angeles back). Checked 2026-10-28T16:47:52Z.
  • 2026-12-23–2026-12-28 (return 5 days later): Axel-exclusive $212.35 · Airline $224.00 · Save $11.65 · See flights for these dates Frontier Airlines (out SEA–DEN 1916 13:37–17:26, back DEN–SEA 2349 / 4203 09:38–17:10; nonstop out, one connection via Las Vegas back). Checked 2026-10-28T16:48:14Z.
  • 2026-12-23–2026-12-28 (return 5 days later): Axel-exclusive $226.92 · Airline $240.00 · Save $13.08 · See flights for these dates Frontier Airlines (out SEA–DEN 1916 13:37–17:26, back DEN–SEA 605 10:08–12:22; nonstop out, nonstop back). Checked 2026-10-28T16:48:14Z.
  • 2026-12-25–2026-12-28 (return 3 days later): Axel-exclusive $230.72 · Airline $243.00 · Save $12.28 · See flights for these dates Frontier Airlines / Alaska Airlines (out SEA–DEN 1916 13:37–17:26, back DEN–SEA 309 21:42–23:49; nonstop out, nonstop back). Checked 2026-11-03T06:10:47Z.
  • 2026-12-25–2026-12-28 (return 3 days later): Axel-exclusive $250.80 · Airline $264.00 · Save $13.20 · See flights for these dates Frontier Airlines (out SEA–DEN 1916 13:37–17:26, back DEN–SEA 777 / 4203 22:44–17:10+1; nonstop out, one connection via Las Vegas back). Arrive home Dec 29. Checked 2026-11-03T06:10:47Z.
  • 2026-12-25–2026-12-28 (return 3 days later): Axel-exclusive $254.06 · Airline $268.00 · Save $13.94 · See flights for these dates Frontier Airlines / Delta Air Lines (out SEA–DEN 1916 13:37–17:26, back DEN–SEA 2543 18:35–20:46; nonstop out, nonstop back). Checked 2026-11-03T06:10:47Z.

January 2027

  • 2027-01-16–2027-01-19 (return 3 days later): Axel-exclusive $243.63 · Airline $257.00 · Save $13.37 · See flights for these dates Southwest Airlines (out SEA–DEN 3485 06:45–10:15, back DEN–SEA 174 15:40–17:40; nonstop out, nonstop back). Checked 2026-10-29T17:22:18Z.
  • 2027-01-16–2027-01-19 (return 3 days later): Axel-exclusive $244.45 · Airline $258.00 · Save $13.55 · See flights for these dates Southwest Airlines / United Airlines (out SEA–DEN 3485 06:45–10:15, back DEN–SEA 2013 16:10–18:12; nonstop out, nonstop back). Checked 2026-10-29T17:22:18Z.
  • 2027-01-16–2027-01-19 (return 3 days later): Axel-exclusive $244.45 · Airline $258.00 · Save $13.55 · See flights for these dates Southwest Airlines / Alaska Airlines (out SEA–DEN 3485 06:45–10:15, back DEN–SEA 493 15:05–17:07; nonstop out, nonstop back). Checked 2026-10-29T17:22:18Z.
  • 2027-01-29–2027-02-01 (return 3 days later): Axel-exclusive $178.50 · Airline $188.00 · Save $9.50 · See flights for these dates Frontier Airlines (out SEA–DEN 1916 16:29–20:19, back DEN–SEA 605 13:03–15:14; nonstop out, nonstop back). Checked 2026-11-02T15:58:29Z.

How we checked

On Nov 2, 2026, Axel priced round trips from SEA to DEN for one adult in economy: 1 Monday and 1 Tuesday departures with returns 6 days later, 1 Wednesday departure with returns 5 days later, 1 Thursday departure with returns 4 days later, 4 Friday, 2 Thursday and 1 Saturday departures with returns 3 days later and 1 Sunday departure with returns 2 days later, November 2026 to January 2027. There are too few comparable week-long date pairs for price targets. Each example keeps its actual return interval. Shorter travel days means same-day arrivals · ≤1 stop · ≤5h out / ≤5h back. Airline prices are the airline’s own fare on Google Flights for the same flights; Axel-exclusive prices need no Membership. Check bags and change rules on your fare.

Airports covered: SEA → DEN. Each example names its actual airports.

See flights for your dates and travelers

Other available fares

Flights by travel date

SEA–DEN · 2026-11-12–2026-11-15 · 1 adult

Round-trip starting price · Economy · USD. Round-trip starting prices; outbound options shown. The final total depends on return selection.

  • Axel-exclusive $303.84 · Frontier Airlines 1178 / 3156 · 19:48–09:45 (November 13, 2026) local · 1 stop (LAX) · 12h 57m. Airline fare: $320.

  • Axel-exclusive $407.55 · Southwest Airlines 4956 · 06:15–09:45 local · Nonstop · 2h 30m. Airline fare: $429.

  • Axel-exclusive $407.55 · United Airlines 757 · 05:05–08:42 local · Nonstop · 2h 37m. Airline fare: $429.

Checked October 27, 2026 at 07:41 PM UTC

SEA–DEN · 2026-11-13–2026-11-16 · 1 adult

Round-trip starting price · Economy · USD. Round-trip starting prices; outbound options shown. The final total depends on return selection.

  • Axel-exclusive $248.53 · Frontier Airlines 1178 / 3156 · 19:48–09:45 (November 14, 2026) local · 1 stop (LAX) · 12h 57m. Airline fare: $263.

  • Axel-exclusive $258.12 · Frontier Airlines 3406 · 16:27–20:15 local · Nonstop · 2h 48m. Airline fare: $273.

  • Axel-exclusive $407.55 · Southwest Airlines 4956 · 06:05–09:35 local · Nonstop · 2h 30m. Airline fare: $429.

Checked October 27, 2026 at 07:40 PM UTC

SEA–DEN · 2026-11-12–2026-11-16 · 1 adult

Round-trip starting price · Economy · USD. Round-trip starting prices; outbound options shown. The final total depends on return selection.

  • Axel-exclusive $248.53 · Frontier Airlines 1178 / 3156 · 19:48–09:45 (November 13, 2026) local · 1 stop (LAX) · 12h 57m. Airline fare: $263.

  • Axel-exclusive $407.55 · Southwest Airlines 4956 · 06:15–09:45 local · Nonstop · 2h 30m. Airline fare: $429.

  • Axel-exclusive $407.55 · United Airlines 757 · 05:05–08:42 local · Nonstop · 2h 37m. Airline fare: $429.

Checked October 27, 2026 at 07:39 PM UTC

SEA–DEN · 2026-12-27–2027-01-03 · 3 adults

Round-trip total · Economy · USD. Complete round-trip total for 3 adults; outbound and return were selected together.

  • Axel-exclusive $816.65 · Alaska Airlines 304 · 20:14–23:59 local · Nonstop · 2h 45m. Return: Alaska Airlines 309 · DEN–SEA · January 3, 2027 · 21:42–23:49 local · Nonstop · 187 minutes. Airline fare: $861. See flights for these dates

Checked October 31, 2026 at 04:10 AM UTC

SEA–DEN · 2026-12-25–2026-12-28 · 1 adult

Round-trip starting price · Economy · USD. Round-trip starting prices; outbound options shown. The final total depends on return selection.

  • Axel-exclusive $230.72 · Frontier Airlines 1916 · 13:37–17:26 local · Nonstop · 2h 49m. Airline fare: $243.

  • Axel-exclusive $262.87 · Alaska Airlines 310 · 17:05–20:44 local · Nonstop · 2h 39m. Airline fare: $277.

  • Axel-exclusive $282.95 · Southwest Airlines 3823 · 13:35–17:05 local · Nonstop · 2h 30m. Airline fare: $298.

Checked November 3, 2026 at 06:10 AM UTC

SEA–DEN · 2026-12-20–2026-12-22 · 1 adult

Round-trip starting price · Economy · USD. Round-trip starting prices; outbound options shown. The final total depends on return selection.

  • Axel-exclusive $226.09 · Alaska Airlines 310 · 17:05–20:44 local · Nonstop · 2h 39m. Airline fare: $239.

  • Axel-exclusive $226.09 · Southwest Airlines 3824 · 20:40–00:20 (December 21, 2026) local · Nonstop · 2h 40m. Airline fare: $239.

  • Axel-exclusive $226.09 · Delta Air Lines 2851 · 19:57–23:46 local · Nonstop · 2h 49m. Airline fare: $239.

Checked November 2, 2026 at 04:15 PM UTC

SEA–DEN · 2026-12-27–2027-01-03 · 3 adults

Round-trip starting price · Economy · USD. Round-trip starting prices; outbound options shown. The final total depends on return selection.

  • Axel-exclusive $786.95 · Delta Air Lines 2851 · 19:57–23:46 local · Nonstop · 2h 49m. Airline fare: $831.

  • Axel-exclusive $816.65 · Alaska Airlines 304 · 20:14–23:59 local · Nonstop · 2h 45m. Airline fare: $861.

  • Axel-exclusive $1,183.44 · Southwest Airlines 3824 · 20:40–00:20 (December 28, 2026) local · Nonstop · 2h 40m. Airline fare: $1,251.

Checked October 31, 2026 at 04:09 AM UTC

SEA–DEN · 2026-12-21–2026-12-27 · 1 adult

Round-trip starting price · Economy · USD. Round-trip starting prices; outbound options shown. The final total depends on return selection.

  • Axel-exclusive $250.80 · Frontier Airlines 4204 / 4968 · 18:25–12:18 (December 22, 2026) local · 1 stop (LAS) · 16h 53m. Airline fare: $264.

  • Axel-exclusive $262.87 · Delta Air Lines 2543 · 13:55–17:40 local · Nonstop · 2h 45m. Airline fare: $277.

  • Axel-exclusive $397.10 · Southwest Airlines 3823 · 14:30–17:55 local · Nonstop · 2h 25m. Airline fare: $418.

Checked October 28, 2026 at 04:49 PM UTC

SEA–DEN · 2027-01-13 · 1 adult

One-way price · Economy · USD. One-way prices for 1 adult.

Checked November 2, 2026 at 03:57 PM UTC

SEA–DEN · 2027-01-11 · 1 adult

One-way price · Economy · USD. One-way prices for 1 adult.

Checked November 2, 2026 at 03:56 PM UTC

SEA–DEN · 2027-01-12 · 1 adult

One-way price · Economy · USD. One-way prices for 1 adult.

Checked November 2, 2026 at 03:56 PM UTC

SEA–DEN · 2027-01-29–2027-02-01 · 1 adult

Round-trip starting price · Economy · USD. Round-trip starting prices; outbound options shown. The final total depends on return selection.

  • Axel-exclusive $178.50 · Frontier Airlines 1916 · 16:29–20:19 local · Nonstop · 2h 50m. Airline fare: $188.

  • Axel-exclusive $262.87 · Southwest Airlines 520 · 06:45–10:15 local · Nonstop · 2h 30m. Airline fare: $277.

  • Axel-exclusive $262.87 · Alaska Airlines 310 · 19:59–23:39 local · Nonstop · 2h 40m. Airline fare: $277.

Checked November 2, 2026 at 03:58 PM UTC

SEA–DEN · 2027-01-16–2027-01-19 · 1 adult

Round-trip starting price · Economy · USD. Round-trip starting prices; outbound options shown. The final total depends on return selection.

  • Axel-exclusive $201.92 · Frontier Airlines 1916 · 16:29–20:19 local · Nonstop · 2h 50m. Airline fare: $213.

  • Axel-exclusive $243.63 · Southwest Airlines 3485 · 06:45–10:15 local · Nonstop · 2h 30m. Airline fare: $257.

  • Axel-exclusive $243.63 · Alaska Airlines 310 · 19:37–23:17 local · Nonstop · 2h 40m. Airline fare: $257.

Checked October 29, 2026 at 05:22 PM UTC

SEA–DEN · 2027-03-25 · 1 adult

One-way price · Economy · USD. One-way prices for 1 adult.

Checked October 31, 2026 at 03:43 PM UTC

SEA–DEN · 2027-03-25–2027-03-29 · 2 adults

Round-trip total · Economy · USD. Complete round-trip total for 2 adults; outbound and return were selected together.

  • Axel-exclusive $581.17 · Alaska Airlines 1586 · 15:45–19:31 local · Nonstop · 2h 46m. Return: Frontier Airlines 605 · DEN–SEA · March 29, 2027 · 13:03–15:14 local · Nonstop · 191 minutes. Airline fare: $615. See flights for these dates

  • Axel-exclusive $619.66 · Alaska Airlines 1586 · 15:45–19:31 local · Nonstop · 2h 46m. Return: United Airlines 2651 · DEN–SEA · March 29, 2027 · 21:00–22:59 local · Nonstop · 179 minutes. Airline fare: $654. See flights for these dates

  • Axel-exclusive $619.66 · Alaska Airlines 1586 · 15:45–19:31 local · Nonstop · 2h 46m. Return: Alaska Airlines 724 · DEN–SEA · March 29, 2027 · 15:00–17:01 local · Nonstop · 181 minutes. Airline fare: $654. See flights for these dates

Checked October 31, 2026 at 03:06 PM UTC

SEA–DEN · 2027-03-25–2027-03-29 · 2 adults

Round-trip starting price · Economy · USD. Round-trip starting prices; outbound options shown. The final total depends on return selection.

  • Axel-exclusive $581.17 · United Airlines 757 · 19:10–22:51 local · Nonstop · 2h 41m. Airline fare: $615.

  • Axel-exclusive $581.17 · Delta Air Lines 1940 · 13:50–17:35 local · Nonstop · 2h 45m. Airline fare: $615.

  • Axel-exclusive $581.17 · Alaska Airlines 1586 · 15:45–19:31 local · Nonstop · 2h 46m. Airline fare: $615.

Checked October 31, 2026 at 03:06 PM UTC

Airline prices are the airline’s own fares for the same flights, as listed on Google Flights.

Airline ratings: Alaska Airlines 7.6/10 · Frontier Airlines 4.4/10 · Southwest Airlines 6.9/10 · Delta Air Lines 7.5/10 · United Airlines 6.4/10 · American Airlines 6.2/10. Every airline rated.

Planning: When to book Thanksgiving flights · Flying in December: prices, crowds and delays · How far in advance to book flights · The cheapest days of the week to fly and to book.

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Source: https://helloaxel.com/en/flights/from-seattle-sea-to-denver-den

Hotels in Denver with Axel

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Where to stay: Where to stay in Denver: the 6 best neighborhoods, ranked · Denver hotels where a family of four can share one room

Hotel details in Denver: DoubleTree by Hilton Hotel Denver · Holiday Inn Express Denver Downtown by IHG · Plaza Hotel Denver · Staybridge Suites Denver - Cherry Creek by IHG · DoubleTree by Hilton Denver Cherry Creek · All 82 hotels in Denver

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