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Dulles → San Juan

Jan 21, 2027 · return Feb 4, 2027

IAD → SJU1 adulteconomyRound trip

9 flight options · 3 airlines

Nonstop flights

Thu, Jan 21 – Thu, Feb 4

Frontier Airlines
1:05 pmIAD
3h 47m
Nonstop
5:52 pmSJU
Frontier Airlines
8:28 amSJU
4h 3m
Nonstop
11:31 amIAD

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

United Airlines
5:29 pmIAD
3h 53m
Nonstop
10:22 pmSJU
United Airlines
8:05 amSJU
4h 4m
Nonstop
11:09 amIAD

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

United Airlines
8:22 amIAD
3h 53m
Nonstop
1:15 pmSJU
United Airlines
8:05 amSJU
4h 4m
Nonstop
11:09 amIAD

Round-trip total · 1 adult · Taxes included

One-stop flights

Thu, Jan 21 – Thu, Feb 4

Delta Air Lines
10:11 amIAD
6h 35m
ATL · 1h 17m
5:46 pmSJU
United Airlines
8:05 amSJU
4h 4m
Nonstop
11:09 amIAD

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

Frontier Airlines
12:26 pmIAD
3h 49m
Nonstop
5:15 pmSJU
Frontier Airlines
3:55 amSJU
7h 26m
MCO · 2h
10:21 amIAD

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

Frontier Airlines
3:41 pmIAD
6h 50m
FLL · 1h 19m
11:31 pmSJU
Frontier Airlines
8:28 amSJU
4h 3m
Nonstop
11:31 amIAD

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

United Airlines
6:10 amIAD
7h 30m
EWR · 2h 22m
2:40 pmSJU
United Airlines
8:05 amSJU
4h 4m
Nonstop
11:09 amIAD

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

United Airlines
6:10 amIAD
8h 30m
ORD · 1h 20m
3:40 pmSJU
United Airlines
8:05 amSJU
4h 4m
Nonstop
11:09 amIAD

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

Delta Air Lines
6:20 pmIAD
7h 23m
JFK · 1h 49m
2:43 am+1SJU
United Airlines
8:05 amSJU
4h 4m
Nonstop
11:09 amIAD

Round-trip total · 1 adult · Taxes included

Make this trip yours

IAD ⇄ SJU

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 AirlinesF91940 / F91939$255.002026-10-29T01:07:59Z
2027-01-21 → 2027-02-04United AirlinesUA2025 / UA2022$445.002026-10-29T01:07:59Z
2027-01-21 → 2027-02-04Delta Air Lines / United AirlinesDL1324 + DL1946 / UA2022$430.002026-10-29T01:07:59Z
2027-01-21 → 2027-02-04United AirlinesUA2021 / UA2022$445.002026-10-29T01:07:59Z
2027-01-21 → 2027-02-04Frontier AirlinesF91940 / F91823 + F94230$265.002026-10-29T01:07:59Z
2027-01-21 → 2027-02-04Frontier AirlinesF92959 + F94916 / F91939$265.002026-10-29T01:07:59Z
2027-01-21 → 2027-02-04United AirlinesUA1359 + UA1556 / UA2022$425.002026-10-29T01:07:59Z
2027-01-21 → 2027-02-04United AirlinesUA565 + UA1996 / UA2022$425.002026-10-29T01:07:59Z
2027-01-21 → 2027-02-04Delta Air Lines / United AirlinesDL5815 + DL1874 / UA2022$430.002026-10-29T01:07:59Z

2027-01-21 → 2027-02-04 · $255.00

  • Frontier Airlines F91940: IAD 2027-01-21 13:05:00 → SJU 2027-01-21 17:52:00; nonstop; 227 minutes. Local airport times.
  • Frontier Airlines F91939: SJU 2027-02-04 08:28:00 → IAD 2027-02-04 11:31:00; nonstop; 243 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $445.00

  • United Airlines UA2025: IAD 2027-01-21 17:29:00 → SJU 2027-01-21 22:22:00; nonstop; 233 minutes. Local airport times.
  • United Airlines UA2022: SJU 2027-02-04 08:05:00 → IAD 2027-02-04 11:09:00; nonstop; 244 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $430.00

  • Delta Air Lines DL1324 / DL1946: IAD 2027-01-21 10:11:00 → SJU 2027-01-21 17:46:00; 1 stop(s) via ATL; 395 minutes. Local airport times.
    • DL1324: IAD 2027-01-21 10:11:00 → ATL 2027-01-21 12:04:00; layover at ATL: 77 minutes.
    • DL1946: ATL 2027-01-21 13:21:00 → SJU 2027-01-21 17:46:00.
  • United Airlines UA2022: SJU 2027-02-04 08:05:00 → IAD 2027-02-04 11:09:00; nonstop; 244 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $445.00

  • United Airlines UA2021: IAD 2027-01-21 08:22:00 → SJU 2027-01-21 13:15:00; nonstop; 233 minutes. Local airport times.
  • United Airlines UA2022: SJU 2027-02-04 08:05:00 → IAD 2027-02-04 11:09:00; nonstop; 244 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $265.00

  • Frontier Airlines F91940: IAD 2027-01-21 12:26:00 → SJU 2027-01-21 17:15:00; nonstop; 229 minutes. Local airport times.
  • Frontier Airlines F91823 / F94230: SJU 2027-02-04 03:55:00 → IAD 2027-02-04 10:21:00; 1 stop(s) via MCO; 446 minutes. Local airport times.
    • F91823: SJU 2027-02-04 03:55:00 → MCO 2027-02-04 06:00:00; layover at MCO: 120 minutes.
    • F94230: MCO 2027-02-04 08:00:00 → IAD 2027-02-04 10:21:00.

2027-01-21 → 2027-02-04 · $265.00

  • Frontier Airlines F92959 / F94916: IAD 2027-01-21 15:41:00 → SJU 2027-01-21 23:31:00; 1 stop(s) via FLL; 410 minutes. Local airport times.
    • F92959: IAD 2027-01-21 15:41:00 → FLL 2027-01-21 18:32:00; layover at FLL: 79 minutes.
    • F94916: FLL 2027-01-21 19:51:00 → SJU 2027-01-21 23:31:00.
  • Frontier Airlines F91939: SJU 2027-02-04 08:28:00 → IAD 2027-02-04 11:31:00; nonstop; 243 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $425.00

  • United Airlines UA1359 / UA1556: IAD 2027-01-21 06:10:00 → SJU 2027-01-21 14:40:00; 1 stop(s) via EWR; 450 minutes. Local airport times.
    • UA1359: IAD 2027-01-21 06:10:00 → EWR 2027-01-21 07:28:00; layover at EWR: 142 minutes.
    • UA1556: EWR 2027-01-21 09:50:00 → SJU 2027-01-21 14:40:00.
  • United Airlines UA2022: SJU 2027-02-04 08:05:00 → IAD 2027-02-04 11:09:00; nonstop; 244 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $425.00

  • United Airlines UA565 / UA1996: IAD 2027-01-21 06:10:00 → SJU 2027-01-21 15:40:00; 1 stop(s) via ORD; 510 minutes. Local airport times.
    • UA565: IAD 2027-01-21 06:10:00 → ORD 2027-01-21 07:32:00; layover at ORD: 80 minutes.
    • UA1996: ORD 2027-01-21 08:52:00 → SJU 2027-01-21 15:40:00.
  • United Airlines UA2022: SJU 2027-02-04 08:05:00 → IAD 2027-02-04 11:09:00; nonstop; 244 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $430.00

  • Delta Air Lines DL5815 / DL1874: IAD 2027-01-21 18:20:00 → SJU 2027-01-22 02:43:00; 1 stop(s) via JFK; 443 minutes. Local airport times.
    • DL5815: IAD 2027-01-21 18:20:00 → JFK 2027-01-21 19:57:00; layover at JFK: 109 minutes.
    • DL1874: JFK 2027-01-21 21:46:00 → SJU 2027-01-22 02:43:00.
  • United Airlines UA2022: SJU 2027-02-04 08:05:00 → IAD 2027-02-04 11:09:00; nonstop; 244 minutes. Local airport times.

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