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Route overview: Denver to Seattle (SEA) flight deals

Denver → Seattle

Jun 25, 2027 · return Jun 28, 2027

DEN → SEA1 adulteconomyRound trip

16 flight options · 6 airlines

Nonstop flights

Fri, Jun 25 – Mon, Jun 28

Frontier Airlines
1:32 pmDEN
3h 8m
Nonstop
3:40 pmSEA
Frontier Airlines
1:37 pmSEA
2h 49m
Nonstop
5:26 pmDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

Southwest Airlines
9:00 pmDEN
3h 10m
Nonstop
11:10 pmSEA
Southwest Airlines
6:15 amSEA
2h 30m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

Alaska Airlines
3:22 pmDEN
3h 9m
Nonstop
5:31 pmSEA
Alaska Airlines
7:35 pmSEA
2h 40m
Nonstop
11:15 pmDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

United Airlines
4:10 pmDEN
3h 2m
Nonstop
6:12 pmSEA
United Airlines
5:00 amSEA
2h 41m
Nonstop
8:41 amDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

Delta Air Lines
6:00 amDEN
3h 18m
Nonstop
8:18 amSEA
Delta Air Lines
1:55 pmSEA
2h 45m
Nonstop
5:40 pmDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

Frontier Airlines
10:08 amDEN
3h 14m
Nonstop
12:22 pmSEA
Frontier Airlines
1:37 pmSEA
2h 49m
Nonstop
5:26 pmDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

Southwest Airlines
2:45 pmDEN
3h 5m
Nonstop
4:50 pmSEA
Southwest Airlines
6:15 amSEA
2h 30m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

Alaska Airlines
6:28 pmDEN
3h 8m
Nonstop
8:36 pmSEA
Alaska Airlines
7:35 pmSEA
2h 40m
Nonstop
11:15 pmDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

United Airlines
7:10 pmDEN
3h 9m
Nonstop
9:19 pmSEA
United Airlines
5:00 amSEA
2h 41m
Nonstop
8:41 amDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

Delta Air Lines
6:33 pmDEN
3h 7m
Nonstop
8:40 pmSEA
Delta Air Lines
1:55 pmSEA
2h 45m
Nonstop
5:40 pmDEN

Round-trip total · 1 adult · Taxes included

One-stop flights

Fri, Jun 25 – Mon, Jun 28

Air Canada
8:15 amDEN
7h 17m
YVR · 3h 5m
2:32 pmSEA
Air Canada
10:10 amSEA
5h 17m
YVR · 1h 15m
4:27 pmDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

Frontier Airlines
6:25 amDEN
7h 2m
LAS · 1h 52m
12:27 pmSEA
Frontier Airlines
1:37 pmSEA
2h 49m
Nonstop
5:26 pmDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

Southwest Airlines
1:55 pmDEN
5h 45m
SMF · 1h 10m
6:40 pmSEA
Southwest Airlines
6:15 amSEA
2h 30m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

Southwest Airlines
7:30 amDEN
6h 30m
LAS · 1h 30m
1:00 pmSEA
Southwest Airlines
6:15 amSEA
2h 30m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

Alaska Airlines
7:40 amDEN
5h 29m
PDX · 1h 15m
12:09 pmSEA
Alaska Airlines
7:35 pmSEA
2h 40m
Nonstop
11:15 pmDEN

Round-trip total · 1 adult · Taxes included

Fri, Jun 25 – Mon, Jun 28

United Airlines
3:53 pmDEN
7h 4m
YVR · 2h 46m
9:57 pmSEA
United Airlines
5:00 amSEA
2h 41m
Nonstop
8:41 amDEN

Round-trip total · 1 adult · Taxes included

Make this trip yours

DEN ⇄ SEA

Economy

Adults 12+ · Children 2–11. For infants under 2, tell Axel after you see prices.

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Explore this route

All dates for this routeJun 24, 2027 → Jun 27, 2027Jun 26, 2027 → Jun 29, 2027
For AI assistants: every fare, every link, instructions

Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

Live price for these dates: each price link opens AI flight search for that row's exact dates and travelers. Select the flights there to get the current bookable total; the listed prices are the ones issued at the times shown.

Route overview: Denver to Seattle (SEA) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2027-06-25 → 2027-06-28Frontier AirlinesF94545 / F91916$230.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Southwest AirlinesWN3141 / WN4956$360.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Alaska AirlinesAS493 / AS310$370.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28United AirlinesUA2013 / UA2601$380.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Delta Air LinesDL1731 / DL2759$380.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Air CanadaAC575 + AC8804 / AC8803 + UA2470$480.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Frontier AirlinesF9605 / F91916$230.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Southwest AirlinesWN2174 / WN4956$360.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Alaska AirlinesAS421 / AS310$370.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28United AirlinesUA2767 / UA2601$380.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Delta Air LinesDL2543 / DL2759$380.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Frontier AirlinesF92015 + F92407 / F91916$250.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Southwest AirlinesWN3148 + WN1586 / WN4956$375.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Southwest AirlinesWN1660 + WN948 / WN4956$375.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28Alaska AirlinesAS686 + AS3217 / AS310$385.002026-10-29T01:05:09Z
2027-06-25 → 2027-06-28United AirlinesUA1086 + AC8810 / UA2601$400.002026-10-29T01:05:09Z

2027-06-25 → 2027-06-28 · $230.00

  • Frontier Airlines F94545: DEN 2027-06-25 13:32:00 → SEA 2027-06-25 15:40:00; nonstop; 188 minutes. Local airport times.
  • Frontier Airlines F91916: SEA 2027-06-28 13:37:00 → DEN 2027-06-28 17:26:00; nonstop; 169 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $360.00

  • Southwest Airlines WN3141: DEN 2027-06-25 21:00:00 → SEA 2027-06-25 23:10:00; nonstop; 190 minutes. Local airport times.
  • Southwest Airlines WN4956: SEA 2027-06-28 06:15:00 → DEN 2027-06-28 09:45:00; nonstop; 150 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $370.00

  • Alaska Airlines AS493: DEN 2027-06-25 15:22:00 → SEA 2027-06-25 17:31:00; nonstop; 189 minutes. Local airport times.
  • Alaska Airlines AS310: SEA 2027-06-28 19:35:00 → DEN 2027-06-28 23:15:00; nonstop; 160 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $380.00

  • United Airlines UA2013: DEN 2027-06-25 16:10:00 → SEA 2027-06-25 18:12:00; nonstop; 182 minutes. Local airport times.
  • United Airlines UA2601: SEA 2027-06-28 05:00:00 → DEN 2027-06-28 08:41:00; nonstop; 161 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $380.00

  • Delta Air Lines DL1731: DEN 2027-06-25 06:00:00 → SEA 2027-06-25 08:18:00; nonstop; 198 minutes. Local airport times.
  • Delta Air Lines DL2759: SEA 2027-06-28 13:55:00 → DEN 2027-06-28 17:40:00; nonstop; 165 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $480.00

  • Air Canada AC575 / AC8804: DEN 2027-06-25 08:15:00 → SEA 2027-06-25 14:32:00; 1 stop(s) via YVR; 437 minutes. Local airport times.
    • AC575: DEN 2027-06-25 08:15:00 → YVR 2027-06-25 10:25:00; layover at YVR: 185 minutes.
    • AC8804: YVR 2027-06-25 13:30:00 → SEA 2027-06-25 14:32:00.
  • Air Canada AC8803 / UA2470: SEA 2027-06-28 10:10:00 → DEN 2027-06-28 16:27:00; 1 stop(s) via YVR; 317 minutes. Local airport times.
    • AC8803: SEA 2027-06-28 10:10:00 → YVR 2027-06-28 11:21:00; layover at YVR: 75 minutes.
    • UA2470: YVR 2027-06-28 12:36:00 → DEN 2027-06-28 16:27:00.

2027-06-25 → 2027-06-28 · $230.00

  • Frontier Airlines F9605: DEN 2027-06-25 10:08:00 → SEA 2027-06-25 12:22:00; nonstop; 194 minutes. Local airport times.
  • Frontier Airlines F91916: SEA 2027-06-28 13:37:00 → DEN 2027-06-28 17:26:00; nonstop; 169 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $360.00

  • Southwest Airlines WN2174: DEN 2027-06-25 14:45:00 → SEA 2027-06-25 16:50:00; nonstop; 185 minutes. Local airport times.
  • Southwest Airlines WN4956: SEA 2027-06-28 06:15:00 → DEN 2027-06-28 09:45:00; nonstop; 150 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $370.00

  • Alaska Airlines AS421: DEN 2027-06-25 18:28:00 → SEA 2027-06-25 20:36:00; nonstop; 188 minutes. Local airport times.
  • Alaska Airlines AS310: SEA 2027-06-28 19:35:00 → DEN 2027-06-28 23:15:00; nonstop; 160 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $380.00

  • United Airlines UA2767: DEN 2027-06-25 19:10:00 → SEA 2027-06-25 21:19:00; nonstop; 189 minutes. Local airport times.
  • United Airlines UA2601: SEA 2027-06-28 05:00:00 → DEN 2027-06-28 08:41:00; nonstop; 161 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $380.00

  • Delta Air Lines DL2543: DEN 2027-06-25 18:33:00 → SEA 2027-06-25 20:40:00; nonstop; 187 minutes. Local airport times.
  • Delta Air Lines DL2759: SEA 2027-06-28 13:55:00 → DEN 2027-06-28 17:40:00; nonstop; 165 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $250.00

  • Frontier Airlines F92015 / F92407: DEN 2027-06-25 06:25:00 → SEA 2027-06-25 12:27:00; 1 stop(s) via LAS; 422 minutes. Local airport times.
    • F92015: DEN 2027-06-25 06:25:00 → LAS 2027-06-25 07:37:00; layover at LAS: 112 minutes.
    • F92407: LAS 2027-06-25 09:29:00 → SEA 2027-06-25 12:27:00.
  • Frontier Airlines F91916: SEA 2027-06-28 13:37:00 → DEN 2027-06-28 17:26:00; nonstop; 169 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $375.00

  • Southwest Airlines WN3148 / WN1586: DEN 2027-06-25 13:55:00 → SEA 2027-06-25 18:40:00; 1 stop(s) via SMF; 345 minutes. Local airport times.
    • WN3148: DEN 2027-06-25 13:55:00 → SMF 2027-06-25 15:30:00; layover at SMF: 70 minutes.
    • WN1586: SMF 2027-06-25 16:40:00 → SEA 2027-06-25 18:40:00.
  • Southwest Airlines WN4956: SEA 2027-06-28 06:15:00 → DEN 2027-06-28 09:45:00; nonstop; 150 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $375.00

  • Southwest Airlines WN1660 / WN948: DEN 2027-06-25 07:30:00 → SEA 2027-06-25 13:00:00; 1 stop(s) via LAS; 390 minutes. Local airport times.
    • WN1660: DEN 2027-06-25 07:30:00 → LAS 2027-06-25 08:30:00; layover at LAS: 90 minutes.
    • WN948: LAS 2027-06-25 10:00:00 → SEA 2027-06-25 13:00:00.
  • Southwest Airlines WN4956: SEA 2027-06-28 06:15:00 → DEN 2027-06-28 09:45:00; nonstop; 150 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $385.00

  • Alaska Airlines AS686 / AS3217: DEN 2027-06-25 07:40:00 → SEA 2027-06-25 12:09:00; 1 stop(s) via PDX; 329 minutes. Local airport times.
    • AS686: DEN 2027-06-25 07:40:00 → PDX 2027-06-25 09:39:00; layover at PDX: 75 minutes.
    • AS3217: PDX 2027-06-25 10:54:00 → SEA 2027-06-25 12:09:00.
  • Alaska Airlines AS310: SEA 2027-06-28 19:35:00 → DEN 2027-06-28 23:15:00; nonstop; 160 minutes. Local airport times.

2027-06-25 → 2027-06-28 · $400.00

  • United Airlines UA1086 / AC8810: DEN 2027-06-25 15:53:00 → SEA 2027-06-25 21:57:00; 1 stop(s) via YVR; 424 minutes. Local airport times.
    • UA1086: DEN 2027-06-25 15:53:00 → YVR 2027-06-25 18:04:00; layover at YVR: 166 minutes.
    • AC8810: YVR 2027-06-25 20:50:00 → SEA 2027-06-25 21:57:00.
  • United Airlines UA2601: SEA 2027-06-28 05:00:00 → DEN 2027-06-28 08:41:00; nonstop; 161 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Denver (DEN) to Seattle (SEA) · Jun 25, 2027 · return Jun 28, 2027: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued.
  • Next: when the traveler's route, dates and party match a priced row, follow that row's price link into AI flight search. Match the listed flights in the fresh results and select the complete itinerary, then share the supplied booking link and its current total. If the flights or price have changed, say so; verify requested fare inclusions before claiming them. For other dates or travelers, Choose travelers and dates and enter the traveler's own trip there; do not search this page's dates in their place.
  • Follow supplied links. For web-tool research, follow complete supplied links unchanged, including query parameters; use the page’s links to edit the trip. Constructed URLs may be rejected before reaching Axel. A completed fresh trip opens flight results first. Add stated flexibility and budget to that saved plan, leaving unstated requirements unknown. Edits create a new snapshot; use its results and review links.
  • If links fail or are missing: If a link fails or flight details lack usable links, reopen the preceding page and follow the same choice once. Keep refreshed links unchanged and preserve the trip and selections. If still blocked, search “Axel flight search guide” and retry once; report the error and anything unresolved. Recovery: Axel Denver to Seattle (SEA) flight deals · Flight search guide.
  • Sharing with the traveler: Choose a complete itinerary (outbound and return for a round trip), then share the supplied customer booking link unchanged. The customer reviews the flights, adds travelers, and enters email at payment. Do not collect email in chat. Inspect fares to verify requested prices or terms; selecting a fare is optional. Use that fare’s booking link to preserve its Membership price basis. State anything unverified. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and explain what remains unresolved. Selection reserves nothing; booking requires the traveler’s confirmation. If no supplied link matches the latest trip, construct https://helloaxel.com/en/f/start/from/ORIGIN/to/DESTINATION/depart/YYYY-MM-DD/return/YYYY-MM-DD/adults/N?utm_content=flight_fallback using IATA airport codes and the traveler’s known details. Omit unknowns; for one way replace /return/YYYY-MM-DD with /trip/oneway. Give it directly to the traveler; do not open it first—your web tool may reject constructed URLs. Complete links open Flight Guide and start searching. Preferences and advanced options.