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Route overview: Washington, DC to Lisbon (LIS) flight deals

Dulles → Lisbon

Dec 16, 2026 · return Dec 18, 2026

IAD → LIS1 adulteconomyRound trip

7 flight options · 3 airlines

Nonstop flights

Wed, Dec 16 – Fri, Dec 18

United Airlines
10:30 pmIAD
6h 50m
Nonstop
10:20 am+1LIS
United Airlines
12:20 pmLIS
8h 20m
Nonstop
3:40 pmIAD

Round-trip total · 1 adult · Taxes included

One-stop flights

Wed, Dec 16 – Fri, Dec 18

TAP Air Portugal
10:30 pmIAD
7h 10m
Nonstop
10:40 am+1LIS
TAP Air Portugal
7:30 amLIS
12h 55m
DUB · 1h 40m
3:25 pmIAD

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Fri, Dec 18

Air Canada
4:30 pmIAD
11h 25m
YYZ · 2h 48m
8:55 am+1LIS
Air Canada
12:50 pmLIS
12h 33m
YUL · 2h 30m
8:23 pmIAD

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Fri, Dec 18

United Airlines
10:15 pmIAD
6h 50m
Nonstop
10:05 am+1LIS
TAP Air Portugal
7:30 amLIS
12h 55m
DUB · 1h 40m
3:25 pmIAD

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Fri, Dec 18

United Airlines
6:10 pmIAD
11h 35m
MAD · 2h 35m
10:45 am+1LIS
United Airlines
12:20 pmLIS
8h 20m
Nonstop
3:40 pmIAD

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Fri, Dec 18

United Airlines
5:18 pmIAD
10h 37m
YYZ · 1h 44m
8:55 am+1LIS
United Airlines
12:20 pmLIS
8h 20m
Nonstop
3:40 pmIAD

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Fri, Dec 18

United Airlines
6:20 pmIAD
11h 45m
LHR · 1h 35m
11:05 am+1LIS
United Airlines
12:20 pmLIS
8h 20m
Nonstop
3:40 pmIAD

Round-trip total · 1 adult · Taxes included

Make this trip yours

IAD ⇄ LIS

Economy

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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.

Live price for these dates: opening any fare on this page checks it live and shows the current bookable total for 1 adult. Check live prices for Dulles (IAD) to Lisbon (LIS), Dec 16, 2026 · return Dec 18, 2026

Route overview: Washington, DC to Lisbon (LIS) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-16 → 2026-12-18United AirlinesUA942 / UA943$998.752026-10-29T01:07:18Z
2026-12-16 → 2026-12-18TAP Air PortugalTP234 / TP1322 + UA229$805.502026-10-29T01:07:18Z
2026-12-16 → 2026-12-18Air CanadaAC8619 + AC810 / AC813 + AC8725$869.502026-10-29T01:07:18Z
2026-12-16 → 2026-12-18United Airlines / TAP Air PortugalUA942 / TP1322 + UA229$870.502026-10-29T01:07:18Z
2026-12-16 → 2026-12-18United AirlinesUA260 + TP1011 / UA943$958.752026-10-29T01:07:18Z
2026-12-16 → 2026-12-18United AirlinesUA3453 + AC810 / UA943$958.752026-10-29T01:07:18Z
2026-12-16 → 2026-12-18United AirlinesUA918 + TP1351 / UA943$958.752026-10-29T01:07:18Z

2026-12-16 → 2026-12-18 · $998.75

  • United Airlines UA942: IAD 2026-12-16 22:30:00 → LIS 2026-12-17 10:20:00; nonstop; 410 minutes. Local airport times.
  • United Airlines UA943: LIS 2026-12-18 12:20:00 → IAD 2026-12-18 15:40:00; nonstop; 500 minutes. Local airport times.

2026-12-16 → 2026-12-18 · $805.50

  • TAP Air Portugal TP234: IAD 2026-12-16 22:30:00 → LIS 2026-12-17 10:40:00; nonstop; 430 minutes. Local airport times.
  • TAP Air Portugal TP1322 / UA229: LIS 2026-12-18 07:30:00 → IAD 2026-12-18 15:25:00; 1 stop(s) via DUB; 775 minutes. Local airport times.
    • TP1322: LIS 2026-12-18 07:30:00 → DUB 2026-12-18 10:25:00; layover at DUB: 100 minutes.
    • UA229: DUB 2026-12-18 12:05:00 → IAD 2026-12-18 15:25:00.

2026-12-16 → 2026-12-18 · $869.50

  • Air Canada AC8619 / AC810: IAD 2026-12-16 16:30:00 → LIS 2026-12-17 08:55:00; 1 stop(s) via YYZ; 685 minutes. Local airport times.
    • AC8619: IAD 2026-12-16 16:30:00 → YYZ 2026-12-16 17:57:00; layover at YYZ: 168 minutes.
    • AC810: YYZ 2026-12-16 20:45:00 → LIS 2026-12-17 08:55:00.
  • Air Canada AC813 / AC8725: LIS 2026-12-18 12:50:00 → IAD 2026-12-18 20:23:00; 1 stop(s) via YUL; 753 minutes. Local airport times.
    • AC813: LIS 2026-12-18 12:50:00 → YUL 2026-12-18 15:55:00; layover at YUL: 150 minutes.
    • AC8725: YUL 2026-12-18 18:25:00 → IAD 2026-12-18 20:23:00.

2026-12-16 → 2026-12-18 · $870.50

  • United Airlines UA942: IAD 2026-12-16 22:15:00 → LIS 2026-12-17 10:05:00; nonstop; 410 minutes. Local airport times.
  • TAP Air Portugal TP1322 / UA229: LIS 2026-12-18 07:30:00 → IAD 2026-12-18 15:25:00; 1 stop(s) via DUB; 775 minutes. Local airport times.
    • TP1322: LIS 2026-12-18 07:30:00 → DUB 2026-12-18 10:25:00; layover at DUB: 100 minutes.
    • UA229: DUB 2026-12-18 12:05:00 → IAD 2026-12-18 15:25:00.

2026-12-16 → 2026-12-18 · $958.75

  • United Airlines UA260 / TP1011: IAD 2026-12-16 18:10:00 → LIS 2026-12-17 10:45:00; 1 stop(s) via MAD; 695 minutes. Local airport times.
    • UA260: IAD 2026-12-16 18:10:00 → MAD 2026-12-17 07:45:00; layover at MAD: 155 minutes.
    • TP1011: MAD 2026-12-17 10:20:00 → LIS 2026-12-17 10:45:00.
  • United Airlines UA943: LIS 2026-12-18 12:20:00 → IAD 2026-12-18 15:40:00; nonstop; 500 minutes. Local airport times.

2026-12-16 → 2026-12-18 · $958.75

  • United Airlines UA3453 / AC810: IAD 2026-12-16 17:18:00 → LIS 2026-12-17 08:55:00; 1 stop(s) via YYZ; 637 minutes. Local airport times.
    • UA3453: IAD 2026-12-16 17:18:00 → YYZ 2026-12-16 19:01:00; layover at YYZ: 104 minutes.
    • AC810: YYZ 2026-12-16 20:45:00 → LIS 2026-12-17 08:55:00.
  • United Airlines UA943: LIS 2026-12-18 12:20:00 → IAD 2026-12-18 15:40:00; nonstop; 500 minutes. Local airport times.

2026-12-16 → 2026-12-18 · $958.75

  • United Airlines UA918 / TP1351: IAD 2026-12-16 18:20:00 → LIS 2026-12-17 11:05:00; 1 stop(s) via LHR; 705 minutes. Local airport times.
    • UA918: IAD 2026-12-16 18:20:00 → LHR 2026-12-17 06:40:00; layover at LHR: 95 minutes.
    • TP1351: LHR 2026-12-17 08:15:00 → LIS 2026-12-17 11:05:00.
  • United Airlines UA943: LIS 2026-12-18 12:20:00 → IAD 2026-12-18 15:40:00; nonstop; 500 minutes. Local airport times.

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