Southwest® flights from Boston to San Antonio from $139

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Low fares from Boston to San Antonio

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Boston (BOS)to

San Antonio (SAT)
Depart: 09/11/2026

One-way

Basic

From
$139
Seen: 2 hrs ago

Boston (BOS)to

San Antonio (SAT)
Depart: 09/05/2026

One-way

Basic

From
$139
Seen: 22 hrs ago

Boston (BOS)to

San Antonio (SAT)
Depart: 09/25/2026

One-way

Basic

From
$145
Seen: 17 hrs ago

Boston (BOS)to

San Antonio (SAT)
Depart: 09/30/2026

One-way

Basic

From
$145
Seen: 15 hrs ago

Boston (BOS)to

San Antonio (SAT)
Depart: 08/31/2026

One-way

Basic

From
$145
Seen: 7 hrs ago

Boston (BOS)to

San Antonio (SAT)
Depart: 10/07/2026

One-way

Basic

From
$145
Seen: 2 hrs ago

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Explore flights from Boston to San Antonio

Aug 2026
From$145*
Seen: 7 hrs ago
One Way/Basic
Sep 2026
From$139*
Seen: 2 hrs ago
One Way/Basic
Oct 2026
From$145*
Seen: 23 hrs ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $145
cmp-daily-histogram-bars-legend-max-price-aria-label $475
Displaying fares for August-2026
  • BOS–SAT, 08/01/2026: From $475
    01

    Sat

    AUG

  • BOS–SAT, 08/02/2026: From $380
    02

    Sun

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    Mon

  • BOS–SAT, 08/04/2026: From $375
    04

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    05

    Wed

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    06

    Thu

  • BOS–SAT, 08/07/2026: From $470
    07

    Fri

  • BOS–SAT, 08/08/2026: From $470
    08

    Sat

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    09

    Sun

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    10

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    11

    Tue

  • BOS–SAT, 08/12/2026: From $275
    12

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    13

    Thu

  • BOS–SAT, 08/14/2026: From $225
    14

    Fri

  • BOS–SAT, 08/15/2026: From $275
    15

    Sat

  • BOS–SAT, 08/16/2026: From $314
    16

    Sun

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    17

    Mon

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    18

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    19

    Wed

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    20

    Thu

  • BOS–SAT, 08/21/2026: From $175
    21

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    22

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    23

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    24

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    25

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    26

    Wed

  • BOS–SAT, 08/27/2026: From $152
    27

    Thu

  • BOS–SAT, 08/28/2026: From $175
    28

    Fri

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    29

    Sat

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    30

    Sun

  • BOS–SAT, 08/31/2026: From $145
    31

    Mon

    • Range$145-$475

    *Fares displayed have been collected within the last 24 hours and may no longer be available at time of booking. Additional fees and charges for optional products and services may apply. Modifying this information may result in a different fare. To find the most updated fare, please visit Southwest.com. Fares listed are Basic, which are subject to additional terms and conditions.

    Flight Details

    Departing from:
    Logan International Airport
    Arriving at:
    San Antonio International Airport
    Distance:
    1764 miles

    Route Information

    138† Weekly flights

    † Weekly flights based on DOT published scheduled average flights Monday through Sunday between 9/1/2025 and 9/30/2025. Note: route may not operate every day of the week.

    ‡ Nonstop flights based on DOT published scheduled average flights Monday through Sunday between 9/1/2025 and 9/30/2025.

    Questions we hear the most

    There are 138 weekly flights from Boston to San Antonio on Southwest Airlines.
    To find the lowest fares by day and time to fly Boston to San Antonio with Southwest, check out our Low Fare Calendar.
    You can rent a car at San Antonio International Airport book yours with your flight.
    Yes! Flights from Boston to San Antonio—or from here or there to anywhere—can be changed with no change fees. Fare difference may apply.
    Check the status of your upcoming Southwest flight.
    Check out the Southwest Airlines® Help Center for answers about everything Southwest.

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