Southwest Pet Policy: Fees, Carrier Size and Rules

Yes, in the cabin only. Southwest allows small, vaccinated dogs at least 8 weeks old in an approved carrier under the seat for a pet fare each way, paid at the ticket counter.

Checked:

Yes

Yes, in the cabin only. Southwest allows small, vaccinated dogs at least 8 weeks old in an approved carrier under the seat for a pet fare each way, paid at the ticket counter. No cargo transport is offered. Since March 2021 Southwest only accepts trained service dogs, not emotional support animals, which must fly as standard pets.

Rules for flying Southwest Airlines with a dog

Southwest Airlines pet fees

WhatFee
In-cabin pet fare, one-way (US mainland)$125.00 one-way
In-cabin pet fare, one-way (inter-island Hawaii)$35.00 one-way

Carrier, age and breed limits

Carrier size18.5 x 9.5 x 13.5 in (soft or hard-sided)
Pets per passenger2
Minimum age8 weeks
Cargonot offered

Service animals and emotional support animals

Only trained service dogs travel free as service animals; ESAs do not qualify.

Since March 1, 2021 Southwest no longer recognizes emotional support animals as service animals; ESAs must travel under the standard paid pet policy.

Good to know: Pet fare amount and exact carrier-per-flight limits can change; Southwest's own help center did not state the dollar fee directly in the fetched page, so the $125 figure is corroborated from multiple secondary sources rather than directly quoted from southwest.com.

Something changed? Tell us: hello@puppymethod.com · Checked September 23, 2026

Sources

  1. Pet Policy | Southwest Airlines — Southwest Airlines Support (September 23, 2026)
  2. Southwest Airlines Pet Policy: 2026 Fees, Carrier Size, Weight Limits & Booking Rules — CitizenShipper (September 23, 2026)