Seattle (SEA) to Porto (OPO) flights from USD737

*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 USD737
cmp-daily-histogram-bars-legend-max-price-aria-label USD1.3K
Displaying fares for September-2026
  • SEA–OPO, 09/24/2026 – 10/15/2026: From USD992
    24

    Th

    SEP

  • SEA–OPO, 09/25/2026 – 10/09/2026: From USD992
    25

    Fr

  • SEA–OPO, 09/26/2026 – 10/10/2026: From USD1,056
    26

    Sa

  • SEA–OPO, 09/27/2026 – 10/11/2026: From USD999
    27

    Su

  • SEA–OPO, 09/28/2026 – 10/12/2026: From USD932
    28

    Mo

  • SEA–OPO, 09/29/2026 – 10/13/2026: From USD932
    29

    Tu

  • SEA–OPO, 09/30/2026 – 10/07/2026: From USD1,103
    30

    We

  • SEA–OPO, 10/01/2026 – 10/08/2026: From USD1,255
    01

    Th

    OCT

  • SEA–OPO, 10/02/2026 – 10/09/2026: From USD1,243
    02

    Fr

  • SEA–OPO, 10/03/2026 – 10/10/2026: From USD1,060
    03

    Sa

  • SEA–OPO, 10/04/2026 – 10/11/2026: From USD1,000
    04

    Su

  • SEA–OPO, 10/05/2026 – 10/12/2026: From USD932
    05

    Mo

  • SEA–OPO, 10/06/2026 – 11/03/2026: From USD907
    06

    Tu

  • SEA–OPO, 10/07/2026 – 11/04/2026: From USD1,068
    07

    We

  • SEA–OPO, 10/08/2026 – 11/05/2026: From USD1,195
    08

    Th

  • SEA–OPO, 10/09/2026 – 11/06/2026: From USD959
    09

    Fr

  • SEA–OPO, 10/10/2026 – 11/07/2026: From USD1,009
    10

    Sa

  • SEA–OPO, 10/11/2026 – 11/08/2026: From USD949
    11

    Su

  • SEA–OPO, 10/12/2026 – 10/19/2026: From USD932
    12

    Mo

  • SEA–OPO, 10/13/2026 – 11/10/2026: From USD874
    13

    Tu

  • SEA–OPO, 10/14/2026 – 11/11/2026: From USD866
    14

    We

  • SEA–OPO, 10/15/2026 – 11/05/2026: From USD916
    15

    Th

  • SEA–OPO, 10/16/2026 – 11/06/2026: From USD916
    16

    Fr

  • SEA–OPO, 10/17/2026 – 11/07/2026: From USD966
    17

    Sa

  • SEA–OPO, 10/18/2026 – 11/08/2026: From USD916
    18

    Su

  • SEA–OPO, 10/19/2026 – 11/09/2026: From USD916
    19

    Mo

  • SEA–OPO, 10/20/2026 – 11/17/2026: From USD745
    20

    Tu

  • SEA–OPO, 10/21/2026 – 11/11/2026: From USD737
    21

    We

  • SEA–OPO, 10/22/2026 – 11/19/2026: From USD787
    22

    Th

  • SEA–OPO, 10/23/2026 – 11/13/2026: From USD787
    23

    Fr

  • RangeUSD737-USD1,255