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Route overview: Washington, DC to Seattle (SEA) flight deals

Dulles → Seattle

Dec 21, 2026 · return Dec 26, 2026

IAD → SEA1 adulteconomyRound trip

9 flight options · 4 airlines

Nonstop flights

Mon, Dec 21 – Sat, Dec 26

Alaska Airlines
5:31 pmIAD
6h 1m
Nonstop
8:32 pmSEA
Alaska Airlines
9:45 pmSEA
4h 55m
Nonstop
5:40 am+1IAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Sat, Dec 26

United Airlines
5:55 pmIAD
6h 7m
Nonstop
9:02 pmSEA
United Airlines
8:09 amSEA
4h 59m
Nonstop
4:08 pmIAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Sat, Dec 26

Alaska Airlines
7:46 amIAD
5h 50m
Nonstop
10:36 amSEA
Alaska Airlines
9:45 pmSEA
4h 55m
Nonstop
5:40 am+1IAD

Round-trip total · 1 adult · Taxes included

One-stop flights

Mon, Dec 21 – Sat, Dec 26

Sun Country Airlines
12:44 pmIAD
7h 33m
MSP · 1h 4m
5:17 pmSEA
Alaska Airlines
9:45 pmSEA
4h 55m
Nonstop
5:40 am+1IAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Sat, Dec 26

Delta Air Lines
7:00 amIAD
6h 5m
Nonstop
10:05 amSEA
Delta Air Lines
1:25 pmSEA
7h 22m
SLC · 1h 25m
11:47 pmIAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Sat, Dec 26

United Airlines
8:15 amIAD
8h 20m
DEN · 1h 3m
1:35 pmSEA
United Airlines
5:00 amSEA
7h 44m
DEN · 1h 39m
3:44 pmIAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Sat, Dec 26

United Airlines
6:10 amIAD
9h 51m
EWR · 2h 12m
1:01 pmSEA
United Airlines
5:00 amSEA
7h 44m
DEN · 1h 39m
3:44 pmIAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Sat, Dec 26

United Airlines
6:10 amIAD
9h 9m
ORD · 1h 53m
12:19 pmSEA
United Airlines
5:00 amSEA
7h 44m
DEN · 1h 39m
3:44 pmIAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Sat, Dec 26

United Airlines
5:55 pmIAD
6h 6m
Nonstop
9:01 pmSEA
United Airlines
5:00 amSEA
7h 44m
DEN · 1h 39m
3:44 pmIAD

Round-trip total · 1 adult · Taxes included

Make this trip yours

IAD ⇄ SEA

Economy

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Explore this route

All dates for this routeDec 20, 2026 → Dec 25, 2026Dec 22, 2026 → Dec 27, 2026
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.

Route overview: Washington, DC to Seattle (SEA) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-21 → 2026-12-26Alaska AirlinesAS737 / AS367$486.002026-10-29T01:07:59Z
2026-12-21 → 2026-12-26United AirlinesUA1128 / UA672$526.502026-10-29T01:07:59Z
2026-12-21 → 2026-12-26Sun Country Airlines / Alaska AirlinesSY668 + SY285 / AS367$418.502026-10-29T01:07:59Z
2026-12-21 → 2026-12-26Delta Air LinesDL1015 / DL1120 + DL847$492.752026-10-29T01:07:59Z
2026-12-21 → 2026-12-26Alaska AirlinesAS409 / AS367$486.002026-10-29T01:07:59Z
2026-12-21 → 2026-12-26United AirlinesUA792 + UA2302 / UA2601 + UA2087$472.502026-10-29T01:07:59Z
2026-12-21 → 2026-12-26United AirlinesUA1359 + UA1330 / UA2601 + UA2087$472.502026-10-29T01:07:59Z
2026-12-21 → 2026-12-26United AirlinesUA565 + UA2099 / UA2601 + UA2087$472.502026-10-29T01:07:59Z
2026-12-21 → 2026-12-26United AirlinesUA1128 / UA2601 + UA2087$499.502026-10-29T01:07:59Z

2026-12-21 → 2026-12-26 · $486.00

  • Alaska Airlines AS737: IAD 2026-12-21 17:31:00 → SEA 2026-12-21 20:32:00; nonstop; 361 minutes. Local airport times.
  • Alaska Airlines AS367: SEA 2026-12-26 21:45:00 → IAD 2026-12-27 05:40:00; nonstop; 295 minutes. Local airport times.

2026-12-21 → 2026-12-26 · $526.50

  • United Airlines UA1128: IAD 2026-12-21 17:55:00 → SEA 2026-12-21 21:02:00; nonstop; 367 minutes. Local airport times.
  • United Airlines UA672: SEA 2026-12-26 08:09:00 → IAD 2026-12-26 16:08:00; nonstop; 299 minutes. Local airport times.

2026-12-21 → 2026-12-26 · $418.50

  • Sun Country Airlines SY668 / SY285: IAD 2026-12-21 12:44:00 → SEA 2026-12-21 17:17:00; 1 stop(s) via MSP; 453 minutes. Local airport times.
    • SY668: IAD 2026-12-21 12:44:00 → MSP 2026-12-21 14:21:00; layover at MSP: 64 minutes.
    • SY285: MSP 2026-12-21 15:25:00 → SEA 2026-12-21 17:17:00.
  • Alaska Airlines AS367: SEA 2026-12-26 21:45:00 → IAD 2026-12-27 05:40:00; nonstop; 295 minutes. Local airport times.

2026-12-21 → 2026-12-26 · $492.75

  • Delta Air Lines DL1015: IAD 2026-12-21 07:00:00 → SEA 2026-12-21 10:05:00; nonstop; 365 minutes. Local airport times.
  • Delta Air Lines DL1120 / DL847: SEA 2026-12-26 13:25:00 → IAD 2026-12-26 23:47:00; 1 stop(s) via SLC; 442 minutes. Local airport times.
    • DL1120: SEA 2026-12-26 13:25:00 → SLC 2026-12-26 16:26:00; layover at SLC: 85 minutes.
    • DL847: SLC 2026-12-26 17:51:00 → IAD 2026-12-26 23:47:00.

2026-12-21 → 2026-12-26 · $486.00

  • Alaska Airlines AS409: IAD 2026-12-21 07:46:00 → SEA 2026-12-21 10:36:00; nonstop; 350 minutes. Local airport times.
  • Alaska Airlines AS367: SEA 2026-12-26 21:45:00 → IAD 2026-12-27 05:40:00; nonstop; 295 minutes. Local airport times.

2026-12-21 → 2026-12-26 · $472.50

  • United Airlines UA792 / UA2302: IAD 2026-12-21 08:15:00 → SEA 2026-12-21 13:35:00; 1 stop(s) via DEN; 500 minutes. Local airport times.
    • UA792: IAD 2026-12-21 08:15:00 → DEN 2026-12-21 10:27:00; layover at DEN: 63 minutes.
    • UA2302: DEN 2026-12-21 11:30:00 → SEA 2026-12-21 13:35:00.
  • United Airlines UA2601 / UA2087: SEA 2026-12-26 05:00:00 → IAD 2026-12-26 15:44:00; 1 stop(s) via DEN; 464 minutes. Local airport times.
    • UA2601: SEA 2026-12-26 05:00:00 → DEN 2026-12-26 08:41:00; layover at DEN: 99 minutes.
    • UA2087: DEN 2026-12-26 10:20:00 → IAD 2026-12-26 15:44:00.

2026-12-21 → 2026-12-26 · $472.50

  • United Airlines UA1359 / UA1330: IAD 2026-12-21 06:10:00 → SEA 2026-12-21 13:01:00; 1 stop(s) via EWR; 591 minutes. Local airport times.
    • UA1359: IAD 2026-12-21 06:10:00 → EWR 2026-12-21 07:28:00; layover at EWR: 132 minutes.
    • UA1330: EWR 2026-12-21 09:40:00 → SEA 2026-12-21 13:01:00.
  • United Airlines UA2601 / UA2087: SEA 2026-12-26 05:00:00 → IAD 2026-12-26 15:44:00; 1 stop(s) via DEN; 464 minutes. Local airport times.
    • UA2601: SEA 2026-12-26 05:00:00 → DEN 2026-12-26 08:41:00; layover at DEN: 99 minutes.
    • UA2087: DEN 2026-12-26 10:20:00 → IAD 2026-12-26 15:44:00.

2026-12-21 → 2026-12-26 · $472.50

  • United Airlines UA565 / UA2099: IAD 2026-12-21 06:10:00 → SEA 2026-12-21 12:19:00; 1 stop(s) via ORD; 549 minutes. Local airport times.
    • UA565: IAD 2026-12-21 06:10:00 → ORD 2026-12-21 07:32:00; layover at ORD: 113 minutes.
    • UA2099: ORD 2026-12-21 09:25:00 → SEA 2026-12-21 12:19:00.
  • United Airlines UA2601 / UA2087: SEA 2026-12-26 05:00:00 → IAD 2026-12-26 15:44:00; 1 stop(s) via DEN; 464 minutes. Local airport times.
    • UA2601: SEA 2026-12-26 05:00:00 → DEN 2026-12-26 08:41:00; layover at DEN: 99 minutes.
    • UA2087: DEN 2026-12-26 10:20:00 → IAD 2026-12-26 15:44:00.

2026-12-21 → 2026-12-26 · $499.50

  • United Airlines UA1128: IAD 2026-12-21 17:55:00 → SEA 2026-12-21 21:01:00; nonstop; 366 minutes. Local airport times.
  • United Airlines UA2601 / UA2087: SEA 2026-12-26 05:00:00 → IAD 2026-12-26 15:44:00; 1 stop(s) via DEN; 464 minutes. Local airport times.
    • UA2601: SEA 2026-12-26 05:00:00 → DEN 2026-12-26 08:41:00; layover at DEN: 99 minutes.
    • UA2087: DEN 2026-12-26 10:20:00 → IAD 2026-12-26 15:44:00.

Explore this route