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Seattle → Denver

Dec 21, 2026 · return Jan 4, 2027

SEA → DEN1 adulteconomyRound trip

15 flight options · 7 airlines

Nonstop flights

Mon, Dec 21 – Mon, Jan 4

Frontier Airlines
1:37 pmSEA
2h 49m
Nonstop
5:26 pmDEN
Frontier Airlines
1:04 pmDEN
3h 8m
Nonstop
3:12 pmSEA

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Jan 4

Southwest Airlines
2:30 pmSEA
2h 25m
Nonstop
5:55 pmDEN
Southwest Airlines
3:40 pmDEN
3h 10m
Nonstop
5:50 pmSEA

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Jan 4

Alaska Airlines
1:50 pmSEA
2h 40m
Nonstop
5:30 pmDEN
Alaska Airlines
3:22 pmDEN
3h 9m
Nonstop
5:31 pmSEA

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Jan 4

Delta Air Lines
7:59 pmSEA
2h 49m
Nonstop
11:48 pmDEN
Delta Air Lines
6:35 pmDEN
3h 11m
Nonstop
8:46 pmSEA

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Jan 4

United Airlines
5:00 amSEA
2h 41m
Nonstop
8:41 amDEN
United Airlines
11:30 amDEN
3h 5m
Nonstop
1:35 pmSEA

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Jan 4

Southwest Airlines
6:15 amSEA
2h 30m
Nonstop
9:45 amDEN
Southwest Airlines
3:40 pmDEN
3h 10m
Nonstop
5:50 pmSEA

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Jan 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

Mon, Dec 21 – Mon, Jan 4

Delta Air Lines
1:55 pmSEA
2h 45m
Nonstop
5:40 pmDEN
Delta Air Lines
6:35 pmDEN
3h 11m
Nonstop
8:46 pmSEA

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Jan 4

United Airlines
7:10 pmSEA
2h 45m
Nonstop
10:55 pmDEN
United Airlines
11:30 amDEN
3h 5m
Nonstop
1:35 pmSEA

Round-trip total · 1 adult · Taxes included

One-stop flights

Mon, Dec 21 – Mon, Jan 4

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

Mon, Dec 21 – Mon, Jan 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

Mon, Dec 21 – Mon, Jan 4

Southwest Airlines
5:15 amSEA
6h 15m
SMF · 2h 10m
12:30 pmDEN
Southwest Airlines
3:40 pmDEN
3h 10m
Nonstop
5:50 pmSEA

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Jan 4

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

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Jan 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

Mon, Dec 21 – Mon, Jan 4

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

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)
2026-12-21 → 2027-01-04Frontier AirlinesF91916 / F91175$171.502026-10-29T01:14:56Z
2026-12-21 → 2027-01-04Southwest AirlinesWN3823 / WN244$300.132026-10-29T01:14:56Z
2026-12-21 → 2027-01-04Alaska AirlinesAS421 / AS493$306.252026-10-29T01:14:56Z
2026-12-21 → 2027-01-04Delta Air LinesDL2851 / DL2543$318.502026-10-29T01:14:56Z
2026-12-21 → 2027-01-04United AirlinesUA2601 / UA2302$330.752026-10-29T01:14:56Z
2026-12-21 → 2027-01-04American Airlines / United AirlinesAA2073 + AA4952 / UA2302$359.752026-10-29T01:14:56Z
2026-12-21 → 2027-01-04Air CanadaAC8803 + UA2470 / AC575 + AC8804$471.632026-10-29T01:14:56Z
2026-12-21 → 2027-01-04Southwest AirlinesWN4956 / WN244$300.132026-10-29T01:14:56Z
2026-12-21 → 2027-01-04Alaska AirlinesAS310 / AS493$306.252026-10-29T01:14:56Z
2026-12-21 → 2027-01-04Delta Air LinesDL2759 / DL2543$318.502026-10-29T01:14:56Z
2026-12-21 → 2027-01-04United AirlinesUA1218 / UA2302$330.752026-10-29T01:14:56Z
2026-12-21 → 2027-01-04Southwest AirlinesWN3833 + WN2542 / WN244$321.882026-10-29T01:14:56Z
2026-12-21 → 2027-01-04Southwest AirlinesWN3434 + WN1410 / WN244$321.882026-10-29T01:14:56Z
2026-12-21 → 2027-01-04Alaska AirlinesAS2238 + AS684 / AS493$335.252026-10-29T01:14:56Z
2026-12-21 → 2027-01-04Delta Air LinesDL1120 + DL1586 / DL2543$347.502026-10-29T01:14:56Z

2026-12-21 → 2027-01-04 · $171.50

  • Frontier Airlines F91916: SEA 2026-12-21 13:37:00 → DEN 2026-12-21 17:26:00; nonstop; 169 minutes. Local airport times.
  • Frontier Airlines F91175: DEN 2027-01-04 13:04:00 → SEA 2027-01-04 15:12:00; nonstop; 188 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $300.13

  • Southwest Airlines WN3823: SEA 2026-12-21 14:30:00 → DEN 2026-12-21 17:55:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN244: DEN 2027-01-04 15:40:00 → SEA 2027-01-04 17:50:00; nonstop; 190 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $306.25

  • Alaska Airlines AS421: SEA 2026-12-21 13:50:00 → DEN 2026-12-21 17:30:00; nonstop; 160 minutes. Local airport times.
  • Alaska Airlines AS493: DEN 2027-01-04 15:22:00 → SEA 2027-01-04 17:31:00; nonstop; 189 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $318.50

  • Delta Air Lines DL2851: SEA 2026-12-21 19:59:00 → DEN 2026-12-21 23:48:00; nonstop; 169 minutes. Local airport times.
  • Delta Air Lines DL2543: DEN 2027-01-04 18:35:00 → SEA 2027-01-04 20:46:00; nonstop; 191 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $330.75

  • United Airlines UA2601: SEA 2026-12-21 05:00:00 → DEN 2026-12-21 08:41:00; nonstop; 161 minutes. Local airport times.
  • United Airlines UA2302: DEN 2027-01-04 11:30:00 → SEA 2027-01-04 13:35:00; nonstop; 185 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $359.75

  • American Airlines AA2073 / AA4952: SEA 2026-12-21 15:00:00 → DEN 2026-12-21 22:58:00; 1 stop(s) via PHX; 418 minutes. Local airport times.
    • AA2073: SEA 2026-12-21 15:00:00 → PHX 2026-12-21 18:52:00; layover at PHX: 127 minutes.
    • AA4952: PHX 2026-12-21 20:59:00 → DEN 2026-12-21 22:58:00.
  • United Airlines UA2302: DEN 2027-01-04 11:30:00 → SEA 2027-01-04 13:35:00; nonstop; 185 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $471.63

  • Air Canada AC8803 / UA2470: SEA 2026-12-21 10:10:00 → DEN 2026-12-21 16:27:00; 1 stop(s) via YVR; 317 minutes. Local airport times.
    • AC8803: SEA 2026-12-21 10:10:00 → YVR 2026-12-21 12:21:00; layover at YVR: 75 minutes.
    • UA2470: YVR 2026-12-21 13:36:00 → DEN 2026-12-21 16:27:00.
  • Air Canada AC575 / AC8804: DEN 2027-01-04 08:15:00 → SEA 2027-01-04 14:32:00; 1 stop(s) via YVR; 437 minutes. Local airport times.
    • AC575: DEN 2027-01-04 08:15:00 → YVR 2027-01-04 11:25:00; layover at YVR: 185 minutes.
    • AC8804: YVR 2027-01-04 14:30:00 → SEA 2027-01-04 14:32:00.

2026-12-21 → 2027-01-04 · $300.13

  • Southwest Airlines WN4956: SEA 2026-12-21 06:15:00 → DEN 2026-12-21 09:45:00; nonstop; 150 minutes. Local airport times.
  • Southwest Airlines WN244: DEN 2027-01-04 15:40:00 → SEA 2027-01-04 17:50:00; nonstop; 190 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $306.25

  • Alaska Airlines AS310: SEA 2026-12-21 19:35:00 → DEN 2026-12-21 23:15:00; nonstop; 160 minutes. Local airport times.
  • Alaska Airlines AS493: DEN 2027-01-04 15:22:00 → SEA 2027-01-04 17:31:00; nonstop; 189 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $318.50

  • Delta Air Lines DL2759: SEA 2026-12-21 13:55:00 → DEN 2026-12-21 17:40:00; nonstop; 165 minutes. Local airport times.
  • Delta Air Lines DL2543: DEN 2027-01-04 18:35:00 → SEA 2027-01-04 20:46:00; nonstop; 191 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $330.75

  • United Airlines UA1218: SEA 2026-12-21 19:10:00 → DEN 2026-12-21 22:55:00; nonstop; 165 minutes. Local airport times.
  • United Airlines UA2302: DEN 2027-01-04 11:30:00 → SEA 2027-01-04 13:35:00; nonstop; 185 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $321.88

  • Southwest Airlines WN3833 / WN2542: SEA 2026-12-21 05:15:00 → DEN 2026-12-21 12:30:00; 1 stop(s) via SMF; 375 minutes. Local airport times.
    • WN3833: SEA 2026-12-21 05:15:00 → SMF 2026-12-21 07:05:00; layover at SMF: 130 minutes.
    • WN2542: SMF 2026-12-21 09:15:00 → DEN 2026-12-21 12:30:00.
  • Southwest Airlines WN244: DEN 2027-01-04 15:40:00 → SEA 2027-01-04 17:50:00; nonstop; 190 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $321.88

  • Southwest Airlines WN3434 / WN1410: SEA 2026-12-21 05:40:00 → DEN 2026-12-21 13:10:00; 1 stop(s) via PHX; 390 minutes. Local airport times.
    • WN3434: SEA 2026-12-21 05:40:00 → PHX 2026-12-21 09:30:00; layover at PHX: 110 minutes.
    • WN1410: PHX 2026-12-21 11:20:00 → DEN 2026-12-21 13:10:00.
  • Southwest Airlines WN244: DEN 2027-01-04 15:40:00 → SEA 2027-01-04 17:50:00; nonstop; 190 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $335.25

  • Alaska Airlines AS2238 / AS684: SEA 2026-12-21 07:38:00 → DEN 2026-12-21 14:24:00; 1 stop(s) via PDX; 346 minutes. Local airport times.
    • AS2238: SEA 2026-12-21 07:38:00 → PDX 2026-12-21 08:35:00; layover at PDX: 129 minutes.
    • AS684: PDX 2026-12-21 10:44:00 → DEN 2026-12-21 14:24:00.
  • Alaska Airlines AS493: DEN 2027-01-04 15:22:00 → SEA 2027-01-04 17:31:00; nonstop; 189 minutes. Local airport times.

2026-12-21 → 2027-01-04 · $347.50

  • Delta Air Lines DL1120 / DL1586: SEA 2026-12-21 13:25:00 → DEN 2026-12-21 20:32:00; 1 stop(s) via SLC; 367 minutes. Local airport times.
    • DL1120: SEA 2026-12-21 13:25:00 → SLC 2026-12-21 16:26:00; layover at SLC: 153 minutes.
    • DL1586: SLC 2026-12-21 18:59:00 → DEN 2026-12-21 20:32:00.
  • Delta Air Lines DL2543: DEN 2027-01-04 18:35:00 → SEA 2027-01-04 20:46:00; nonstop; 191 minutes. Local airport times.

More dates for this route