Flights from Great Falls to Porto from $ 796*

Promotion Code

Changed bag rules and optional services         Cruise Packages

Featured daily fares for flights from Great Falls (GTF) to Porto (OPO)

Mar 2026
From$ 867*
Viewed: 1 day ago
RoundTrip|Economy
Apr 2026
From$ 796*
Viewed: 1 day ago
RoundTrip|Economy
May 2026
From$ 951*
Viewed: 1 day ago
RoundTrip|Economy
$ 796
$ 2.2K
Displaying fares for March-2026
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    • Range$ 796-$ 2,172

    *Prices have been available for round trips within the last 48 hours and may not be currently available. For Economy class, fares listed may be Basic Economy, which is our most restrictive fare option and subject to additional restrictions. Additional baggage charges and fees for other optional service may apply. Other terms and conditions may apply. Schedules are subject to change without notice.

    More United deals on Great Falls (GTF) to Porto (OPO) flights

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    More United deals on Great Falls (GTF) to Porto (OPO) flights
    From
    To
    Fare Type
    Dates
    Price
    Great Falls (GTF)Porto (OPO)Roundtrip
    |
    Economy    		04/15/26 - 04/22/26

    from

    $ 796

    Viewed: 1 day ago

    Great Falls (GTF)Porto (OPO)Roundtrip
    |
    Economy    		04/15/26 - 04/29/26

    from

    $ 796

    Viewed: 1 day ago

    Great Falls (GTF)Porto (OPO)Roundtrip
    |
    Economy    		04/21/26 - 04/28/26

    from

    $ 822

    Viewed: 1 day ago

    Great Falls (GTF)Porto (OPO)Roundtrip
    |
    Economy    		03/24/26 - 03/31/26

    from

    $ 867

    Viewed: 1 day ago

    Great Falls (GTF)Porto (OPO)Roundtrip
    |
    Economy    		04/21/26 - 05/05/26

    from

    $ 867

    Viewed: 1 day ago

    Great Falls (GTF)Porto (OPO)Roundtrip
    |
    Economy    		04/25/26 - 05/02/26

    from

    $ 882

    Viewed: 1 day ago

    Great Falls (GTF)Porto (OPO)Roundtrip
    |
    Economy    		04/16/26 - 04/20/26

    from

    $ 884

    Viewed: 1 day ago

    Great Falls (GTF)Porto (OPO)Roundtrip
    |
    Economy    		04/07/26 - 04/14/26

    from

    $ 886

    Viewed: 1 day ago

    *Prices have been available for round trips within the last 48 hours and may not be currently available. For Economy class, fares listed may be Basic Economy, which is our most restrictive fare option and subject to additional restrictions. Additional baggage charges and fees for other optional service may apply. Other terms and conditions may apply. Schedules are subject to change without notice.

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