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Seattle → Denver

Jan 21, 2027 · return Feb 4, 2027

SEA → DEN1 adulteconomyRound trip

15 flight options · 6 airlines

Nonstop flights

Thu, Jan 21 – Thu, Feb 4

Frontier Airlines
4:37 pmSEA
2h 48m
Nonstop
8:25 pmDEN
Frontier Airlines
1:32 pmDEN
3h 8m
Nonstop
3:40 pmSEA

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

Southwest Airlines
2:30 pmSEA
2h 25m
Nonstop
5:55 pmDEN
Southwest Airlines
8:55 pmDEN
3h 10m
Nonstop
11:05 pmSEA

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

Alaska Airlines
3:16 pmSEA
2h 40m
Nonstop
6:56 pmDEN
Alaska Airlines
3:22 pmDEN
3h 9m
Nonstop
5:31 pmSEA

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

Delta Air Lines
8:30 amSEA
2h 52m
Nonstop
12:22 pmDEN
Delta Air Lines
6:33 pmDEN
3h 7m
Nonstop
8:40 pmSEA

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

United Airlines
5:05 amSEA
2h 37m
Nonstop
8:42 amDEN
United Airlines
4:10 pmDEN
3h 2m
Nonstop
6:12 pmSEA

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

Southwest Airlines
9:25 amSEA
2h 35m
Nonstop
1:00 pmDEN
Southwest Airlines
8:55 pmDEN
3h 10m
Nonstop
11:05 pmSEA

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

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

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

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

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

United Airlines
4:04 pmSEA
2h 41m
Nonstop
7:45 pmDEN
United Airlines
4:10 pmDEN
3h 2m
Nonstop
6:12 pmSEA

Round-trip total · 1 adult · Taxes included

One-stop flights

Thu, Jan 21 – Thu, Feb 4

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

Thu, Jan 21 – Thu, Feb 4

Frontier Airlines
4:58 pmSEA
2h 48m
Nonstop
8:46 pmDEN
Frontier Airlines
6:25 amDEN
7h 2m
LAS · 1h 52m
12:27 pmSEA

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

Southwest Airlines
5:15 amSEA
6h 15m
SMF · 2h 10m
12:30 pmDEN
Southwest Airlines
8:55 pmDEN
3h 10m
Nonstop
11:05 pmSEA

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

Alaska Airlines
7:38 amSEA
5h 46m
PDX · 2h 9m
2:24 pmDEN
Alaska Airlines
3:22 pmDEN
3h 9m
Nonstop
5:31 pmSEA

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

Delta Air Lines
1:25 pmSEA
6h 7m
SLC · 2h 33m
8:32 pmDEN
Delta Air Lines
6:33 pmDEN
3h 7m
Nonstop
8:40 pmSEA

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

United Airlines
5:05 amSEA
2h 37m
Nonstop
8:42 amDEN
United Airlines
3:53 pmDEN
7h 4m
YVR · 2h 46m
9:57 pmSEA

Round-trip total · 1 adult · Taxes included

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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More dates

All dates for this routeNov 20, 2026 → Nov 23, 2026Nov 27, 2026 → Dec 4, 2026Nov 20, 2026 · One way
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.

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2027-01-21 → 2027-02-04Frontier AirlinesF91916 / F94545$140.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04Southwest AirlinesWN3823 / WN3141$245.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04Alaska AirlinesAS421 / AS493$250.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04Delta Air LinesDL1358 / DL2543$260.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04United AirlinesUA1686 / UA2013$270.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04Air CanadaAC8803 + UA2470 / AC575 + AC8804$385.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04Southwest AirlinesWN2150 / WN3141$245.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04Alaska AirlinesAS310 / AS493$250.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04Delta Air LinesDL2543 / DL2543$260.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04United AirlinesUA757 / UA2013$270.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04Frontier AirlinesF91916 / F92015 + F92407$160.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04Southwest AirlinesWN3833 + WN2542 / WN3141$260.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04Alaska AirlinesAS2238 + AS684 / AS493$270.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04Delta Air LinesDL1120 + DL1586 / DL2543$280.002026-10-29T01:14:56Z
2027-01-21 → 2027-02-04United AirlinesUA757 / UA1086 + AC8810$290.002026-10-29T01:14:56Z

2027-01-21 → 2027-02-04 · $140.00

  • Frontier Airlines F91916: SEA 2027-01-21 16:37:00 → DEN 2027-01-21 20:25:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F94545: DEN 2027-02-04 13:32:00 → SEA 2027-02-04 15:40:00; nonstop; 188 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $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 WN3141: DEN 2027-02-04 20:55:00 → SEA 2027-02-04 23:05:00; nonstop; 190 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $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 AS493: DEN 2027-02-04 15:22:00 → SEA 2027-02-04 17:31:00; nonstop; 189 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $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 2027-02-04 18:33:00 → SEA 2027-02-04 20:40:00; nonstop; 187 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $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 UA2013: DEN 2027-02-04 16:10:00 → SEA 2027-02-04 18:12:00; nonstop; 182 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $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 2027-02-04 08:15:00 → SEA 2027-02-04 14:32:00; 1 stop(s) via YVR; 437 minutes. Local airport times.
    • AC575: DEN 2027-02-04 08:15:00 → YVR 2027-02-04 11:25:00; layover at YVR: 185 minutes.
    • AC8804: YVR 2027-02-04 14:30:00 → SEA 2027-02-04 14:32:00.

2027-01-21 → 2027-02-04 · $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 WN3141: DEN 2027-02-04 20:55:00 → SEA 2027-02-04 23:05:00; nonstop; 190 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $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 AS493: DEN 2027-02-04 15:22:00 → SEA 2027-02-04 17:31:00; nonstop; 189 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $260.00

  • Delta Air Lines DL2543: SEA 2027-01-21 13:55:00 → DEN 2027-01-21 17:40:00; nonstop; 165 minutes. Local airport times.
  • Delta Air Lines DL2543: DEN 2027-02-04 18:33:00 → SEA 2027-02-04 20:40:00; nonstop; 187 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $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 UA2013: DEN 2027-02-04 16:10:00 → SEA 2027-02-04 18:12:00; nonstop; 182 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $160.00

  • Frontier Airlines F91916: SEA 2027-01-21 16:58:00 → DEN 2027-01-21 20:46:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92015 / F92407: DEN 2027-02-04 06:25:00 → SEA 2027-02-04 12:27:00; 1 stop(s) via LAS; 422 minutes. Local airport times.
    • F92015: DEN 2027-02-04 06:25:00 → LAS 2027-02-04 07:37:00; layover at LAS: 112 minutes.
    • F92407: LAS 2027-02-04 09:29:00 → SEA 2027-02-04 12:27:00.

2027-01-21 → 2027-02-04 · $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 WN3141: DEN 2027-02-04 20:55:00 → SEA 2027-02-04 23:05:00; nonstop; 190 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $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 AS493: DEN 2027-02-04 15:22:00 → SEA 2027-02-04 17:31:00; nonstop; 189 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $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 2027-02-04 18:33:00 → SEA 2027-02-04 20:40:00; nonstop; 187 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $290.00

  • United Airlines UA757: SEA 2027-01-21 05:05:00 → DEN 2027-01-21 08:42:00; nonstop; 157 minutes. Local airport times.
  • United Airlines UA1086 / AC8810: DEN 2027-02-04 15:53:00 → SEA 2027-02-04 21:57:00; 1 stop(s) via YVR; 424 minutes. Local airport times.
    • UA1086: DEN 2027-02-04 15:53:00 → YVR 2027-02-04 19:04:00; layover at YVR: 166 minutes.
    • AC8810: YVR 2027-02-04 21:50:00 → SEA 2027-02-04 21:57:00.

More dates for this route