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Route overview: Washington, DC to Saint Louis (STL) flight deals

Dulles → Saint Louis

Dec 21, 2026 · return Dec 24, 2026

IAD → STL1 adulteconomyRound trip

8 flight options · 4 airlines

Nonstop flights

Mon, Dec 21 – Thu, Dec 24

United Airlines
6:00 pmIAD
2h 35m
Nonstop
7:35 pmSTL
United Airlines
1:17 pmSTL
2h 5m
Nonstop
4:22 pmIAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Thu, Dec 24

United Airlines
5:55 pmIAD
2h 35m
Nonstop
7:30 pmSTL
United Airlines
1:00 pmSTL
2h 9m
Nonstop
4:09 pmIAD

Round-trip total · 1 adult · Taxes included

One-stop flights

Mon, Dec 21 – Thu, Dec 24

American Airlines
6:00 amIAD
5h 19m
CLT · 1h 27m
10:19 amSTL
American Airlines
12:54 pmSTL
5h 39m
CLT · 2h 15m
7:33 pmIAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Thu, Dec 24

Delta Air Lines
12:35 pmIAD
5h 31m
JFK · 1h 9m
5:06 pmSTL
Delta Air Lines
10:14 amSTL
5h 4m
DTW · 1h 59m
4:18 pmIAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Thu, Dec 24

Air Canada
9:55 amIAD
6h 31m
YYZ · 2h 48m
3:26 pmSTL
United Airlines
1:17 pmSTL
2h 5m
Nonstop
4:22 pmIAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Thu, Dec 24

United Airlines
6:10 amIAD
5h 54m
EWR · 1h 32m
11:04 amSTL
United Airlines
1:17 pmSTL
2h 5m
Nonstop
4:22 pmIAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Thu, Dec 24

United Airlines
8:23 amIAD
4h 47m
ORD · 1h
12:10 pmSTL
United Airlines
1:17 pmSTL
2h 5m
Nonstop
4:22 pmIAD

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Thu, Dec 24

Delta Air Lines
12:34 pmIAD
6h 27m
ATL · 2h 49m
6:01 pmSTL
Delta Air Lines
10:14 amSTL
5h 4m
DTW · 1h 59m
4:18 pmIAD

Round-trip total · 1 adult · Taxes included

Make this trip yours

IAD ⇄ STL

Economy

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Explore this route

All dates for this routeDec 20, 2026 → Dec 23, 2026Dec 22, 2026 → Dec 25, 2026
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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 Saint Louis (STL) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-21 → 2026-12-24United AirlinesUA4527 / UA4454$442.002026-10-29T01:07:59Z
2026-12-21 → 2026-12-24American AirlinesAA5649 + AA2486 / AA2486 + AA5317$403.002026-10-29T01:07:59Z
2026-12-21 → 2026-12-24Delta Air LinesDL5618 + DL4715 / DL2868 + DL5413$429.002026-10-29T01:07:59Z
2026-12-21 → 2026-12-24Air Canada / United AirlinesAC8615 + AC8889 / UA4454$572.002026-10-29T01:07:59Z
2026-12-21 → 2026-12-24United AirlinesUA4527 / UA3632$442.002026-10-29T01:07:59Z
2026-12-21 → 2026-12-24United AirlinesUA1359 + UA3571 / UA4454$429.002026-10-29T01:07:59Z
2026-12-21 → 2026-12-24United AirlinesUA1775 + UA2844 / UA4454$429.002026-10-29T01:07:59Z
2026-12-21 → 2026-12-24Delta Air LinesDL1444 + DL1393 / DL2868 + DL5413$429.002026-10-29T01:07:59Z

2026-12-21 → 2026-12-24 · $442.00

  • United Airlines UA4527: IAD 2026-12-21 18:00:00 → STL 2026-12-21 19:35:00; nonstop; 155 minutes. Local airport times.
  • United Airlines UA4454: STL 2026-12-24 13:17:00 → IAD 2026-12-24 16:22:00; nonstop; 125 minutes. Local airport times.

2026-12-21 → 2026-12-24 · $403.00

  • American Airlines AA5649 / AA2486: IAD 2026-12-21 06:00:00 → STL 2026-12-21 10:19:00; 1 stop(s) via CLT; 319 minutes. Local airport times.
    • AA5649: IAD 2026-12-21 06:00:00 → CLT 2026-12-21 07:48:00; layover at CLT: 87 minutes.
    • AA2486: CLT 2026-12-21 09:15:00 → STL 2026-12-21 10:19:00.
  • American Airlines AA2486 / AA5317: STL 2026-12-24 12:54:00 → IAD 2026-12-24 19:33:00; 1 stop(s) via CLT; 339 minutes. Local airport times.
    • AA2486: STL 2026-12-24 12:54:00 → CLT 2026-12-24 15:42:00; layover at CLT: 135 minutes.
    • AA5317: CLT 2026-12-24 17:57:00 → IAD 2026-12-24 19:33:00.

2026-12-21 → 2026-12-24 · $429.00

  • Delta Air Lines DL5618 / DL4715: IAD 2026-12-21 12:35:00 → STL 2026-12-21 17:06:00; 1 stop(s) via JFK; 331 minutes. Local airport times.
    • DL5618: IAD 2026-12-21 12:35:00 → JFK 2026-12-21 14:01:00; layover at JFK: 69 minutes.
    • DL4715: JFK 2026-12-21 15:10:00 → STL 2026-12-21 17:06:00.
  • Delta Air Lines DL2868 / DL5413: STL 2026-12-24 10:14:00 → IAD 2026-12-24 16:18:00; 1 stop(s) via DTW; 304 minutes. Local airport times.
    • DL2868: STL 2026-12-24 10:14:00 → DTW 2026-12-24 12:46:00; layover at DTW: 119 minutes.
    • DL5413: DTW 2026-12-24 14:45:00 → IAD 2026-12-24 16:18:00.

2026-12-21 → 2026-12-24 · $572.00

  • Air Canada AC8615 / AC8889: IAD 2026-12-21 09:55:00 → STL 2026-12-21 15:26:00; 1 stop(s) via YYZ; 391 minutes. Local airport times.
    • AC8615: IAD 2026-12-21 09:55:00 → YYZ 2026-12-21 11:22:00; layover at YYZ: 168 minutes.
    • AC8889: YYZ 2026-12-21 14:10:00 → STL 2026-12-21 15:26:00.
  • United Airlines UA4454: STL 2026-12-24 13:17:00 → IAD 2026-12-24 16:22:00; nonstop; 125 minutes. Local airport times.

2026-12-21 → 2026-12-24 · $442.00

  • United Airlines UA4527: IAD 2026-12-21 17:55:00 → STL 2026-12-21 19:30:00; nonstop; 155 minutes. Local airport times.
  • United Airlines UA3632: STL 2026-12-24 13:00:00 → IAD 2026-12-24 16:09:00; nonstop; 129 minutes. Local airport times.

2026-12-21 → 2026-12-24 · $429.00

  • United Airlines UA1359 / UA3571: IAD 2026-12-21 06:10:00 → STL 2026-12-21 11:04:00; 1 stop(s) via EWR; 354 minutes. Local airport times.
    • UA1359: IAD 2026-12-21 06:10:00 → EWR 2026-12-21 07:28:00; layover at EWR: 92 minutes.
    • UA3571: EWR 2026-12-21 09:00:00 → STL 2026-12-21 11:04:00.
  • United Airlines UA4454: STL 2026-12-24 13:17:00 → IAD 2026-12-24 16:22:00; nonstop; 125 minutes. Local airport times.

2026-12-21 → 2026-12-24 · $429.00

  • United Airlines UA1775 / UA2844: IAD 2026-12-21 08:23:00 → STL 2026-12-21 12:10:00; 1 stop(s) via ORD; 287 minutes. Local airport times.
    • UA1775: IAD 2026-12-21 08:23:00 → ORD 2026-12-21 09:45:00; layover at ORD: 60 minutes.
    • UA2844: ORD 2026-12-21 10:45:00 → STL 2026-12-21 12:10:00.
  • United Airlines UA4454: STL 2026-12-24 13:17:00 → IAD 2026-12-24 16:22:00; nonstop; 125 minutes. Local airport times.

2026-12-21 → 2026-12-24 · $429.00

  • Delta Air Lines DL1444 / DL1393: IAD 2026-12-21 12:34:00 → STL 2026-12-21 18:01:00; 1 stop(s) via ATL; 387 minutes. Local airport times.
    • DL1444: IAD 2026-12-21 12:34:00 → ATL 2026-12-21 14:31:00; layover at ATL: 169 minutes.
    • DL1393: ATL 2026-12-21 17:20:00 → STL 2026-12-21 18:01:00.
  • Delta Air Lines DL2868 / DL5413: STL 2026-12-24 10:14:00 → IAD 2026-12-24 16:18:00; 1 stop(s) via DTW; 304 minutes. Local airport times.
    • DL2868: STL 2026-12-24 10:14:00 → DTW 2026-12-24 12:46:00; layover at DTW: 119 minutes.
    • DL5413: DTW 2026-12-24 14:45:00 → IAD 2026-12-24 16:18:00.

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