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Route overview: Seattle to Denver (DEN) flight deals

Seattle → Denver

Jan 21, 2027 · one way

SEA → DEN1 adulteconomyOne way

15 flight options · 7 airlines

Nonstop flights

Thu, Jan 21 · One way

Frontier Airlines
1:24 pmSEA
2h 49m
Nonstop
5:13 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

Southwest Airlines
9:25 amSEA
2h 35m
Nonstop
1:00 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

Alaska Airlines
3:16 pmSEA
2h 40m
Nonstop
6:56 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

Delta Air Lines
1:30 pmSEA
2h 46m
Nonstop
5:16 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

United Airlines
4:04 pmSEA
2h 41m
Nonstop
7:45 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

Southwest Airlines
2:30 pmSEA
2h 25m
Nonstop
5:55 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

Alaska Airlines
7:35 pmSEA
2h 40m
Nonstop
11:15 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

Delta Air Lines
8:30 amSEA
2h 52m
Nonstop
12:22 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

United Airlines
5:05 amSEA
2h 37m
Nonstop
8:42 amDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

One-stop flights

Thu, Jan 21 · One way

American Airlines
3:00 pmSEA
6h 58m
PHX · 2h 7m
10:58 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

Air Canada
10:10 amSEA
5h 17m
YVR · 1h 15m
4:27 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

Southwest Airlines
5:40 amSEA
6h 30m
PHX · 1h 50m
1:10 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

Southwest Airlines
5:15 amSEA
6h 15m
SMF · 2h 10m
12:30 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

Alaska Airlines
7:38 amSEA
5h 46m
PDX · 2h 9m
2:24 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 · One way

Delta Air Lines
1:25 pmSEA
6h 7m
SLC · 2h 33m
8:32 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Make this trip yours

SEA ⇄ DEN

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 routeJan 20, 2027 · Return optionsJan 22, 2027 · Return optionsHotels in Denver 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)
2027-01-21 · one wayFrontier AirlinesF91916Axel-exclusive $75.002026-10-29T01:14:56Z
2027-01-21 · one waySouthwest AirlinesWN2150Axel-exclusive $130.002026-10-29T01:14:56Z
2027-01-21 · one wayAlaska AirlinesAS421Axel-exclusive $135.002026-10-29T01:14:56Z
2027-01-21 · one wayDelta Air LinesDL3697Axel-exclusive $140.002026-10-29T01:14:56Z
2027-01-21 · one wayUnited AirlinesUA757Axel-exclusive $145.002026-10-29T01:14:56Z
2027-01-21 · one wayAmerican AirlinesAA2073 + AA4952Axel-exclusive $165.002026-10-29T01:14:56Z
2027-01-21 · one wayAir CanadaAC8803 + UA2470Axel-exclusive $205.002026-10-29T01:14:56Z
2027-01-21 · one waySouthwest AirlinesWN3823Axel-exclusive $130.002026-10-29T01:14:56Z
2027-01-21 · one wayAlaska AirlinesAS310Axel-exclusive $135.002026-10-29T01:14:56Z
2027-01-21 · one wayDelta Air LinesDL1358Axel-exclusive $140.002026-10-29T01:14:56Z
2027-01-21 · one wayUnited AirlinesUA1686Axel-exclusive $145.002026-10-29T01:14:56Z
2027-01-21 · one waySouthwest AirlinesWN3434 + WN1410Axel-exclusive $145.002026-10-29T01:14:56Z
2027-01-21 · one waySouthwest AirlinesWN3833 + WN2542Axel-exclusive $145.002026-10-29T01:14:56Z
2027-01-21 · one wayAlaska AirlinesAS2238 + AS684Axel-exclusive $155.002026-10-29T01:14:56Z
2027-01-21 · one wayDelta Air LinesDL1120 + DL1586Axel-exclusive $160.002026-10-29T01:14:56Z

Route overview: Seattle to Denver (DEN) flight deals

2027-01-21 · one way · Axel-exclusive $75.00

  • Frontier Airlines F91916: SEA 2027-01-21 13:24:00 → DEN 2027-01-21 17:13:00; nonstop; 169 minutes. Local airport times.

2027-01-21 · one way · Axel-exclusive $130.00

  • Southwest Airlines WN2150: SEA 2027-01-21 09:25:00 → DEN 2027-01-21 13:00:00; nonstop; 155 minutes. Local airport times.

2027-01-21 · one way · Axel-exclusive $135.00

  • Alaska Airlines AS421: SEA 2027-01-21 15:16:00 → DEN 2027-01-21 18:56:00; nonstop; 160 minutes. Local airport times.

2027-01-21 · one way · Axel-exclusive $140.00

  • Delta Air Lines DL3697: SEA 2027-01-21 13:30:00 → DEN 2027-01-21 17:16:00; nonstop; 166 minutes. Local airport times.

2027-01-21 · one way · Axel-exclusive $145.00

  • United Airlines UA757: SEA 2027-01-21 16:04:00 → DEN 2027-01-21 19:45:00; nonstop; 161 minutes. Local airport times.

2027-01-21 · one way · Axel-exclusive $165.00

  • American Airlines AA2073 / AA4952: SEA 2027-01-21 15:00:00 → DEN 2027-01-21 22:58:00; 1 stop(s) via PHX; 418 minutes. Local airport times.
    • AA2073: SEA 2027-01-21 15:00:00 → PHX 2027-01-21 18:52:00; layover at PHX: 127 minutes.
    • AA4952: PHX 2027-01-21 20:59:00 → DEN 2027-01-21 22:58:00.

2027-01-21 · one way · Axel-exclusive $205.00

  • Air Canada AC8803 / UA2470: SEA 2027-01-21 10:10:00 → DEN 2027-01-21 16:27:00; 1 stop(s) via YVR; 317 minutes. Local airport times.
    • AC8803: SEA 2027-01-21 10:10:00 → YVR 2027-01-21 12:21:00; layover at YVR: 75 minutes.
    • UA2470: YVR 2027-01-21 13:36:00 → DEN 2027-01-21 16:27:00.

2027-01-21 · one way · Axel-exclusive $130.00

  • Southwest Airlines WN3823: SEA 2027-01-21 14:30:00 → DEN 2027-01-21 17:55:00; nonstop; 145 minutes. Local airport times.

2027-01-21 · one way · Axel-exclusive $135.00

  • Alaska Airlines AS310: SEA 2027-01-21 19:35:00 → DEN 2027-01-21 23:15:00; nonstop; 160 minutes. Local airport times.

2027-01-21 · one way · Axel-exclusive $140.00

  • Delta Air Lines DL1358: SEA 2027-01-21 08:30:00 → DEN 2027-01-21 12:22:00; nonstop; 172 minutes. Local airport times.

2027-01-21 · one way · Axel-exclusive $145.00

  • United Airlines UA1686: SEA 2027-01-21 05:05:00 → DEN 2027-01-21 08:42:00; nonstop; 157 minutes. Local airport times.

2027-01-21 · one way · Axel-exclusive $145.00

  • Southwest Airlines WN3434 / WN1410: SEA 2027-01-21 05:40:00 → DEN 2027-01-21 13:10:00; 1 stop(s) via PHX; 390 minutes. Local airport times.
    • WN3434: SEA 2027-01-21 05:40:00 → PHX 2027-01-21 09:30:00; layover at PHX: 110 minutes.
    • WN1410: PHX 2027-01-21 11:20:00 → DEN 2027-01-21 13:10:00.

2027-01-21 · one way · Axel-exclusive $145.00

  • Southwest Airlines WN3833 / WN2542: SEA 2027-01-21 05:15:00 → DEN 2027-01-21 12:30:00; 1 stop(s) via SMF; 375 minutes. Local airport times.
    • WN3833: SEA 2027-01-21 05:15:00 → SMF 2027-01-21 07:05:00; layover at SMF: 130 minutes.
    • WN2542: SMF 2027-01-21 09:15:00 → DEN 2027-01-21 12:30:00.

2027-01-21 · one way · Axel-exclusive $155.00

  • Alaska Airlines AS2238 / AS684: SEA 2027-01-21 07:38:00 → DEN 2027-01-21 14:24:00; 1 stop(s) via PDX; 346 minutes. Local airport times.
    • AS2238: SEA 2027-01-21 07:38:00 → PDX 2027-01-21 08:35:00; layover at PDX: 129 minutes.
    • AS684: PDX 2027-01-21 10:44:00 → DEN 2027-01-21 14:24:00.

2027-01-21 · one way · Axel-exclusive $160.00

  • Delta Air Lines DL1120 / DL1586: SEA 2027-01-21 13:25:00 → DEN 2027-01-21 20:32:00; 1 stop(s) via SLC; 367 minutes. Local airport times.
    • DL1120: SEA 2027-01-21 13:25:00 → SLC 2027-01-21 16:26:00; layover at SLC: 153 minutes.
    • DL1586: SLC 2027-01-21 18:59:00 → DEN 2027-01-21 20:32:00.

Explore this route

For AI assistants

  • This page: Seattle (SEA) to Denver (DEN) · Jan 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 Seattle to Denver (DEN) 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.