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Route overview: Seattle to Denver (DEN) flight deals

Seattle → Denver

Jan 21, 2027 · return Jan 24, 2027

SEA → DEN1 adulteconomyRound trip

15 flight options · 7 airlines

Nonstop flights

Thu, Jan 21 – Sun, Jan 24

Frontier Airlines
1:24 pmSEA
2h 49m
Nonstop
5:13 pmDEN
Frontier Airlines
1:14 pmDEN
3h 8m
Nonstop
3:22 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

Southwest Airlines
2:30 pmSEA
2h 25m
Nonstop
5:55 pmDEN
Southwest Airlines
8:30 amDEN
3h 10m
Nonstop
10:40 amSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

Alaska Airlines
7:35 pmSEA
2h 40m
Nonstop
11:15 pmDEN
Alaska Airlines
7:24 pmDEN
3h 16m
Nonstop
9:40 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

Delta Air Lines
8:30 amSEA
2h 52m
Nonstop
12:22 pmDEN
Delta Air Lines
6:35 pmDEN
3h 11m
Nonstop
8:46 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

United Airlines
5:05 amSEA
2h 37m
Nonstop
8:42 amDEN
United Airlines
11:30 amDEN
3h 5m
Nonstop
1:35 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

Southwest Airlines
9:25 amSEA
2h 35m
Nonstop
1:00 pmDEN
Southwest Airlines
8:30 amDEN
3h 10m
Nonstop
10:40 amSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

Alaska Airlines
3:16 pmSEA
2h 40m
Nonstop
6:56 pmDEN
Alaska Airlines
7:24 pmDEN
3h 16m
Nonstop
9:40 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

Delta Air Lines
1:30 pmSEA
2h 46m
Nonstop
5:16 pmDEN
Delta Air Lines
6:35 pmDEN
3h 11m
Nonstop
8:46 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

United Airlines
4:04 pmSEA
2h 41m
Nonstop
7:45 pmDEN
United Airlines
11:30 amDEN
3h 5m
Nonstop
1:35 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

One-stop flights

Thu, Jan 21 – Sun, Jan 24

American Airlines
3:00 pmSEA
6h 58m
PHX · 2h 7m
10:58 pmDEN
United Airlines
11:30 amDEN
3h 5m
Nonstop
1:35 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

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

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

Southwest Airlines
5:15 amSEA
6h 15m
SMF · 2h 10m
12:30 pmDEN
Southwest Airlines
8:30 amDEN
3h 10m
Nonstop
10:40 amSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

Southwest Airlines
5:40 amSEA
6h 30m
PHX · 1h 50m
1:10 pmDEN
Southwest Airlines
8:30 amDEN
3h 10m
Nonstop
10:40 amSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

Alaska Airlines
7:38 amSEA
5h 46m
PDX · 2h 9m
2:24 pmDEN
Alaska Airlines
7:24 pmDEN
3h 16m
Nonstop
9:40 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sun, Jan 24

Delta Air Lines
1:25 pmSEA
6h 7m
SLC · 2h 33m
8:32 pmDEN
Delta Air Lines
6:35 pmDEN
3h 11m
Nonstop
8:46 pmSEA

Round-trip 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 → 2027-01-24Frontier AirlinesF91916 / F94545Axel-exclusive $140.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24Southwest AirlinesWN3823 / WN1788Axel-exclusive $245.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24Alaska AirlinesAS310 / AS421Axel-exclusive $250.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24Delta Air LinesDL1358 / DL2543Axel-exclusive $260.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24United AirlinesUA1686 / UA2302Axel-exclusive $270.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24American Airlines / United AirlinesAA2073 + AA4952 / UA2302Axel-exclusive $290.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24Air CanadaAC8803 + UA2470 / AC575 + AC8804Axel-exclusive $385.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24Southwest AirlinesWN2150 / WN1788Axel-exclusive $245.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24Alaska AirlinesAS421 / AS421Axel-exclusive $250.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24Delta Air LinesDL3697 / DL2543Axel-exclusive $260.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24United AirlinesUA757 / UA2302Axel-exclusive $270.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24Southwest AirlinesWN3833 + WN2542 / WN1788Axel-exclusive $260.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24Southwest AirlinesWN3434 + WN1410 / WN1788Axel-exclusive $260.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24Alaska AirlinesAS2238 + AS684 / AS421Axel-exclusive $270.002026-10-29T01:14:56Z
2027-01-21 → 2027-01-24Delta Air LinesDL1120 + DL1586 / DL2543Axel-exclusive $280.002026-10-29T01:14:56Z

Route overview: Seattle to Denver (DEN) flight deals

2027-01-21 → 2027-01-24 · Axel-exclusive $140.00

  • Frontier Airlines F91916: SEA 2027-01-21 13:24:00 → DEN 2027-01-21 17:13:00; nonstop; 169 minutes. Local airport times.
  • Frontier Airlines F94545: DEN 2027-01-24 13:14:00 → SEA 2027-01-24 15:22:00; nonstop; 188 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $245.00

  • Southwest Airlines WN3823: SEA 2027-01-21 14:30:00 → DEN 2027-01-21 17:55:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN1788: DEN 2027-01-24 08:30:00 → SEA 2027-01-24 10:40:00; nonstop; 190 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $250.00

  • Alaska Airlines AS310: SEA 2027-01-21 19:35:00 → DEN 2027-01-21 23:15:00; nonstop; 160 minutes. Local airport times.
  • Alaska Airlines AS421: DEN 2027-01-24 19:24:00 → SEA 2027-01-24 21:40:00; nonstop; 196 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $260.00

  • Delta Air Lines DL1358: SEA 2027-01-21 08:30:00 → DEN 2027-01-21 12:22:00; nonstop; 172 minutes. Local airport times.
  • Delta Air Lines DL2543: DEN 2027-01-24 18:35:00 → SEA 2027-01-24 20:46:00; nonstop; 191 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $270.00

  • United Airlines UA1686: SEA 2027-01-21 05:05:00 → DEN 2027-01-21 08:42:00; nonstop; 157 minutes. Local airport times.
  • United Airlines UA2302: DEN 2027-01-24 11:30:00 → SEA 2027-01-24 13:35:00; nonstop; 185 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $290.00

  • 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.
  • United Airlines UA2302: DEN 2027-01-24 11:30:00 → SEA 2027-01-24 13:35:00; nonstop; 185 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $385.00

  • 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.
  • Air Canada AC575 / AC8804: DEN 2027-01-24 08:15:00 → SEA 2027-01-24 14:32:00; 1 stop(s) via YVR; 437 minutes. Local airport times.
    • AC575: DEN 2027-01-24 08:15:00 → YVR 2027-01-24 11:25:00; layover at YVR: 185 minutes.
    • AC8804: YVR 2027-01-24 14:30:00 → SEA 2027-01-24 14:32:00.

2027-01-21 → 2027-01-24 · Axel-exclusive $245.00

  • Southwest Airlines WN2150: SEA 2027-01-21 09:25:00 → DEN 2027-01-21 13:00:00; nonstop; 155 minutes. Local airport times.
  • Southwest Airlines WN1788: DEN 2027-01-24 08:30:00 → SEA 2027-01-24 10:40:00; nonstop; 190 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $250.00

  • Alaska Airlines AS421: SEA 2027-01-21 15:16:00 → DEN 2027-01-21 18:56:00; nonstop; 160 minutes. Local airport times.
  • Alaska Airlines AS421: DEN 2027-01-24 19:24:00 → SEA 2027-01-24 21:40:00; nonstop; 196 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $260.00

  • Delta Air Lines DL3697: SEA 2027-01-21 13:30:00 → DEN 2027-01-21 17:16:00; nonstop; 166 minutes. Local airport times.
  • Delta Air Lines DL2543: DEN 2027-01-24 18:35:00 → SEA 2027-01-24 20:46:00; nonstop; 191 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $270.00

  • United Airlines UA757: SEA 2027-01-21 16:04:00 → DEN 2027-01-21 19:45:00; nonstop; 161 minutes. Local airport times.
  • United Airlines UA2302: DEN 2027-01-24 11:30:00 → SEA 2027-01-24 13:35:00; nonstop; 185 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $260.00

  • 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.
  • Southwest Airlines WN1788: DEN 2027-01-24 08:30:00 → SEA 2027-01-24 10:40:00; nonstop; 190 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $260.00

  • 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.
  • Southwest Airlines WN1788: DEN 2027-01-24 08:30:00 → SEA 2027-01-24 10:40:00; nonstop; 190 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $270.00

  • 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.
  • Alaska Airlines AS421: DEN 2027-01-24 19:24:00 → SEA 2027-01-24 21:40:00; nonstop; 196 minutes. Local airport times.

2027-01-21 → 2027-01-24 · Axel-exclusive $280.00

  • 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.
  • Delta Air Lines DL2543: DEN 2027-01-24 18:35:00 → SEA 2027-01-24 20:46:00; nonstop; 191 minutes. Local airport times.

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For AI assistants

  • This page: Seattle (SEA) to Denver (DEN) · Jan 21, 2027 · return Jan 24, 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 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.