$145 Cheap Southwest Airlines flights Washington (IAD) to Houston (HOU)

You can find affordable round-trip Southwest Airlines flights from $300 from IAD to HOU by organizing your results from “Price (lowest to highest)” on Expedia. Or look for options from $145 for a one-way trip.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

Southwest Airlines flights to Houston are generally more affordable in the low-season months of November and February. Whether you need a one-way or a return ticket, you could score a better deal then.

To find cheap Southwest Airlines fares from Washington Dulles Intl. Airport (IAD) to William P. Hobby Airport (HOU), start searching one to three months before your intended departure. Reserving domestic flights 34 to 86 days in advance could save you 25% compared to booking just 6 to 12 days ahead. The day you book can also influence the overall price. Sunday is generally the cheapest, while Monday is often the most expensive for domestic flights. You can save 6% on average by booking your trip on a Sunday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC’s global airline sales database.

Fill in your dates, hit search and select the “Nonstop” filter on Expedia to browse any direct flights from IAD to HOU with Southwest Airlines or other carriers.

Browse Southwest Airlines’s earliest flights from IAD to HOU by checking our “Morning” and “Early Morning” filters. Not only will you arrive at your destination sooner, early departures are also 20% less likely to be canceled.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.

William P. Hobby Airport (HOU) is the main Houston hub for Southwest Airlines flights from Washington Dulles Intl. Airport (IAD).

Changes are usually free within 24 hours of booking, but your airline may add a charge after that. For further details about altering your reservation, head to your “Trips,” select your flight and click on “Manage Booking.” If you want the freedom to update your itinerary without additional charges, check the “Changes included” and “No cancel fee” filters when planning your trip.