Seattle (SEA) to Basel (BSL) flights from USD626

*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 Basel

cmp-daily-histogram-bars-legend-min-price-aria-label USD656
cmp-daily-histogram-bars-legend-max-price-aria-label USD1.2K
Displaying fares for September-2026
  • SEA–BSL, 09/20/2026 – 09/27/2026: From USD1,009
    20

    Su

    SEP

  • SEA–BSL, 09/21/2026 – 09/28/2026: From USD999
    21

    Mo

  • SEA–BSL, 09/22/2026 – 09/29/2026: From USD934
    22

    Tu

  • SEA–BSL, 09/23/2026 – 09/30/2026: From USD943
    23

    We

  • SEA–BSL, 09/24/2026 – 10/08/2026: From USD1,142
    24

    Th

  • SEA–BSL, 09/25/2026 – 09/28/2026: From USD1,193
    25

    Fr

  • SEA–BSL, 09/26/2026 – 10/24/2026: From USD985
    26

    Sa

  • SEA–BSL, 09/27/2026 – 10/11/2026: From USD914
    27

    Su

  • SEA–BSL, 09/28/2026 – 10/05/2026: From USD729
    28

    Mo

  • SEA–BSL, 09/29/2026 – 10/06/2026: From USD669
    29

    Tu

  • SEA–BSL, 09/30/2026 – 10/07/2026: From USD866
    30

    We

  • SEA–BSL, 10/01/2026 – 10/15/2026: From USD1,007
    01

    Th

    OCT

  • SEA–BSL, 10/02/2026 – 10/05/2026: From USD1,036
    02

    Fr

  • SEA–BSL, 10/03/2026 – 10/10/2026: From USD975
    03

    Sa

  • SEA–BSL, 10/04/2026 – 10/11/2026: From USD725
    04

    Su

  • SEA–BSL, 10/05/2026 – 11/02/2026: From USD718
    05

    Mo

  • SEA–BSL, 10/06/2026 – 11/03/2026: From USD656
    06

    Tu

  • SEA–BSL, 10/07/2026 – 11/04/2026: From USD982
    07

    We

  • SEA–BSL, 10/08/2026 – 11/05/2026: From USD957
    08

    Th

  • SEA–BSL, 10/09/2026 – 11/06/2026: From USD717
    09

    Fr

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

    Sa

  • SEA–BSL, 10/11/2026 – 11/08/2026: From USD696
    11

    Su

  • SEA–BSL, 10/12/2026 – 11/09/2026: From USD707
    12

    Mo

  • SEA–BSL, 10/13/2026 – 11/03/2026: From USD667
    13

    Tu

  • SEA–BSL, 10/14/2026 – 11/11/2026: From USD657
    14

    We

  • SEA–BSL, 10/15/2026 – 11/12/2026: From USD717
    15

    Th

  • SEA–BSL, 10/16/2026 – 11/06/2026: From USD706
    16

    Fr

  • SEA–BSL, 10/17/2026 – 11/07/2026: From USD766
    17

    Sa

  • SEA–BSL, 10/18/2026 – 11/08/2026: From USD696
    18

    Su

  • SEA–BSL, 10/19/2026 – 11/09/2026: From USD700
    19

    Mo

  • RangeUSD656-USD1,193