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Route overview: Denver to Seattle (SEA) flight deals

Denver → Seattle

Jun 21, 2027 · one way

DEN → SEA1 adulteconomyOne way

16 flight options · 6 airlines

Nonstop flights

Mon, Jun 21 · One way

Frontier Airlines
1:32 pmDEN
3h 11m
Nonstop
3:43 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Southwest Airlines
9:00 pmDEN
3h 10m
Nonstop
11:10 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Alaska Airlines
3:22 pmDEN
3h 9m
Nonstop
5:31 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Delta Air Lines
6:35 pmDEN
3h 11m
Nonstop
8:46 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

United Airlines
7:40 amDEN
3h 9m
Nonstop
9:49 amSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Frontier Airlines
10:08 amDEN
3h 14m
Nonstop
12:22 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Southwest Airlines
3:40 pmDEN
3h 10m
Nonstop
5:50 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Alaska Airlines
7:24 pmDEN
3h 16m
Nonstop
9:40 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

United Airlines
7:10 pmDEN
3h 7m
Nonstop
9:17 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Delta Air Lines
6:05 amDEN
3h 18m
Nonstop
8:23 amSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

One-stop flights

Mon, Jun 21 · One way

Air Canada
8:15 amDEN
7h 17m
YVR · 3h 5m
2:32 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Frontier Airlines
6:25 amDEN
7h 2m
LAS · 1h 52m
12:27 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Southwest Airlines
7:30 amDEN
6h 30m
LAS · 1h 30m
1:00 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Southwest Airlines
1:55 pmDEN
5h 45m
SMF · 1h 10m
6:40 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Alaska Airlines
7:40 amDEN
5h 29m
PDX · 1h 15m
12:09 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

United Airlines
3:53 pmDEN
7h 4m
YVR · 2h 46m
9:57 pmSEA

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

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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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. How Axel works · About

Explore this route

All dates for this routeJun 20, 2027 · Return optionsJun 22, 2027 · Return optionsHotels in Seattle with Axel
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.

See flights for these dates: each price link opens AI flight search for that row's exact dates and travelers. Select the complete itinerary there.

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2027-06-21 · one wayFrontier AirlinesF94545Axel-exclusive $120.002026-10-29T01:05:09Z
2027-06-21 · one waySouthwest AirlinesWN3141Axel-exclusive $185.002026-10-29T01:05:09Z
2027-06-21 · one wayAlaska AirlinesAS493Axel-exclusive $190.002026-10-29T01:05:09Z
2027-06-21 · one wayDelta Air LinesDL2543Axel-exclusive $195.002026-10-29T01:05:09Z
2027-06-21 · one wayUnited AirlinesUA2271Axel-exclusive $195.002026-10-29T01:05:09Z
2027-06-21 · one wayAir CanadaAC575 + AC8804Axel-exclusive $250.002026-10-29T01:05:09Z
2027-06-21 · one wayFrontier AirlinesF9605Axel-exclusive $120.002026-10-29T01:05:09Z
2027-06-21 · one waySouthwest AirlinesWN244Axel-exclusive $185.002026-10-29T01:05:09Z
2027-06-21 · one wayAlaska AirlinesAS421Axel-exclusive $190.002026-10-29T01:05:09Z
2027-06-21 · one wayUnited AirlinesUA360Axel-exclusive $195.002026-10-29T01:05:09Z
2027-06-21 · one wayDelta Air LinesDL1731Axel-exclusive $195.002026-10-29T01:05:09Z
2027-06-21 · one wayFrontier AirlinesF92015 + F92407Axel-exclusive $140.002026-10-29T01:05:09Z
2027-06-21 · one waySouthwest AirlinesWN1660 + WN948Axel-exclusive $200.002026-10-29T01:05:09Z
2027-06-21 · one waySouthwest AirlinesWN3148 + WN1586Axel-exclusive $200.002026-10-29T01:05:09Z
2027-06-21 · one wayAlaska AirlinesAS686 + AS3217Axel-exclusive $205.002026-10-29T01:05:09Z
2027-06-21 · one wayUnited AirlinesUA1086 + AC8810Axel-exclusive $215.002026-10-29T01:05:09Z

Route overview: Denver to Seattle (SEA) flight deals

2027-06-21 · one way · Axel-exclusive $120.00

  • Frontier Airlines F94545: DEN 2027-06-21 13:32:00 → SEA 2027-06-21 15:43:00; nonstop; 191 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $185.00

  • Southwest Airlines WN3141: DEN 2027-06-21 21:00:00 → SEA 2027-06-21 23:10:00; nonstop; 190 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $190.00

  • Alaska Airlines AS493: DEN 2027-06-21 15:22:00 → SEA 2027-06-21 17:31:00; nonstop; 189 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $195.00

  • Delta Air Lines DL2543: DEN 2027-06-21 18:35:00 → SEA 2027-06-21 20:46:00; nonstop; 191 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $195.00

  • United Airlines UA2271: DEN 2027-06-21 07:40:00 → SEA 2027-06-21 09:49:00; nonstop; 189 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $250.00

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

2027-06-21 · one way · Axel-exclusive $120.00

  • Frontier Airlines F9605: DEN 2027-06-21 10:08:00 → SEA 2027-06-21 12:22:00; nonstop; 194 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $185.00

  • Southwest Airlines WN244: DEN 2027-06-21 15:40:00 → SEA 2027-06-21 17:50:00; nonstop; 190 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $190.00

  • Alaska Airlines AS421: DEN 2027-06-21 19:24:00 → SEA 2027-06-21 21:40:00; nonstop; 196 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $195.00

  • United Airlines UA360: DEN 2027-06-21 19:10:00 → SEA 2027-06-21 21:17:00; nonstop; 187 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $195.00

  • Delta Air Lines DL1731: DEN 2027-06-21 06:05:00 → SEA 2027-06-21 08:23:00; nonstop; 198 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $140.00

  • Frontier Airlines F92015 / F92407: DEN 2027-06-21 06:25:00 → SEA 2027-06-21 12:27:00; 1 stop(s) via LAS; 422 minutes. Local airport times.
    • F92015: DEN 2027-06-21 06:25:00 → LAS 2027-06-21 07:37:00; layover at LAS: 112 minutes.
    • F92407: LAS 2027-06-21 09:29:00 → SEA 2027-06-21 12:27:00.

2027-06-21 · one way · Axel-exclusive $200.00

  • Southwest Airlines WN1660 / WN948: DEN 2027-06-21 07:30:00 → SEA 2027-06-21 13:00:00; 1 stop(s) via LAS; 390 minutes. Local airport times.
    • WN1660: DEN 2027-06-21 07:30:00 → LAS 2027-06-21 08:30:00; layover at LAS: 90 minutes.
    • WN948: LAS 2027-06-21 10:00:00 → SEA 2027-06-21 13:00:00.

2027-06-21 · one way · Axel-exclusive $200.00

  • Southwest Airlines WN3148 / WN1586: DEN 2027-06-21 13:55:00 → SEA 2027-06-21 18:40:00; 1 stop(s) via SMF; 345 minutes. Local airport times.
    • WN3148: DEN 2027-06-21 13:55:00 → SMF 2027-06-21 15:30:00; layover at SMF: 70 minutes.
    • WN1586: SMF 2027-06-21 16:40:00 → SEA 2027-06-21 18:40:00.

2027-06-21 · one way · Axel-exclusive $205.00

  • Alaska Airlines AS686 / AS3217: DEN 2027-06-21 07:40:00 → SEA 2027-06-21 12:09:00; 1 stop(s) via PDX; 329 minutes. Local airport times.
    • AS686: DEN 2027-06-21 07:40:00 → PDX 2027-06-21 09:39:00; layover at PDX: 75 minutes.
    • AS3217: PDX 2027-06-21 10:54:00 → SEA 2027-06-21 12:09:00.

2027-06-21 · one way · Axel-exclusive $215.00

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

Explore this route

For AI assistants

  • This page: Denver (DEN) to Seattle (SEA) · Jun 21, 2027 · one way: 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. Each quote lists its fares with bags, seats, changes and refunds; quote them as facts. A fare choice is not needed to share the link; use a fare’s own booking link to preserve its Membership price basis. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and say what is still to choose. 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.