Southwest Fare Calendar 2025. This date is subject to change! Visit southwest.com to view the southwest low fare calendar and find the cheapest airfare of the season.

Unlike some fare search tools that only display limited results or promotional fares, southwest’s low fare calendar provides a broad overview of fare trends for each day of the. The airline said on thursday that its passengers will be able to book a reserved seat in late 2025 and those seats will start to become available on flights in early 2026.