Seattle (SEA) to Porto (OPO) flights from USD802

*Modifying this information may result in a different fare

*All amounts are in USD. Taxes and surcharges are included. No booking fee is applicable. Fares displayed have been collected within the last 48hrs and may no longer be available at time of booking. Additional baggage fees may apply.

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Lowest fares between Seattle and Porto

cmp-daily-histogram-bars-legend-min-price-aria-label USD906
cmp-daily-histogram-bars-legend-max-price-aria-label USD1.9K
Displaying fares for August-2026
  • SEA–OPO, 08/13/2026 – 08/20/2026: From USD1,828
    13

    Th

    AUG

  • SEA–OPO, 08/14/2026 – 09/04/2026: From USD1,828
    14

    Fr

  • SEA–OPO, 08/15/2026 – 09/12/2026: From USD1,888
    15

    Sa

  • SEA–OPO, 08/16/2026 – 08/23/2026: From USD1,828
    16

    Su

  • SEA–OPO, 08/17/2026 – 09/14/2026: From USD1,829
    17

    Mo

  • SEA–OPO, 08/18/2026 – 09/08/2026: From USD1,768
    18

    Tu

  • SEA–OPO, 08/19/2026 – 09/02/2026: From USD1,768
    19

    We

  • SEA–OPO, 08/20/2026 – 09/10/2026: From USD1,828
    20

    Th

  • SEA–OPO, 08/21/2026 – 08/28/2026: From USD1,828
    21

    Fr

  • SEA–OPO, 08/22/2026 – 09/12/2026: From USD1,894
    22

    Sa

  • SEA–OPO, 08/23/2026 – 08/30/2026: From USD1,824
    23

    Su

  • SEA–OPO, 08/24/2026 – 09/14/2026: From USD1,824
    24

    Mo

  • SEA–OPO, 08/25/2026 – 09/15/2026: From USD1,764
    25

    Tu

  • SEA–OPO, 08/26/2026 – 09/02/2026: From USD1,764
    26

    We

  • SEA–OPO, 08/27/2026 – 09/24/2026: From USD1,834
    27

    Th

  • SEA–OPO, 08/28/2026 – 09/18/2026: From USD1,834
    28

    Fr

  • SEA–OPO, 08/29/2026 – 09/26/2026: From USD1,894
    29

    Sa

  • SEA–OPO, 08/30/2026 – 09/06/2026: From USD1,824
    30

    Su

  • SEA–OPO, 08/31/2026 – 09/07/2026: From USD1,829
    31

    Mo

  • SEA–OPO, 09/01/2026 – 09/29/2026: From USD1,764
    01

    Tu

    SEP

  • SEA–OPO, 09/02/2026 – 09/23/2026: From USD1,764
    02

    We

  • SEA–OPO, 09/03/2026 – 10/01/2026: From USD1,834
    03

    Th

  • SEA–OPO, 09/04/2026 – 09/25/2026: From USD1,839
    04

    Fr

  • SEA–OPO, 09/05/2026 – 09/12/2026: From USD1,894
    05

    Sa

  • SEA–OPO, 09/06/2026 – 10/04/2026: From USD1,824
    06

    Su

  • SEA–OPO, 09/07/2026 – 09/28/2026: From USD1,824
    07

    Mo

  • SEA–OPO, 09/08/2026 – 09/22/2026: From USD906
    08

    Tu

  • SEA–OPO, 09/09/2026 – 10/07/2026: From USD1,096
    09

    We

  • SEA–OPO, 09/10/2026 – 10/01/2026: From USD976
    10

    Th

  • SEA–OPO, 09/11/2026 – 09/18/2026: From USD1,171
    11

    Fr

  • SEA–OPO, 09/12/2026 – 09/19/2026: From USD1,036
    12

    Sa

  • RangeUSD906-USD1,894