Residents in the Washington area are fortunate to have three major airports at their disposal for when they need to fly, and it’s surprisingly cheap to park your car at them, according to a new study.

BWI Thurgood Marshall Airport has some of the cheapest parking rates among major airports, while Reagan National and Dulles are cheaper than most, a Travelbank.com survey showed.

There’s a lot that goes into choosing whether to fly out of Reagan National, Dulles, or BWI Thurgood Marshall Airports. There’s the proximity to your house or office, traffic to and from the airport, airline selection, availability of flights—and yes, parking rates.

Travelbank.com performed a study of parking rates at the 30 largest airports in America, and BWI rated behind only airports in Charlotte, Orlando and Houston. Parking near the terminal will cost you $22 per day, on average at BWI, and long-term parking averages $8. (And I know from experience there are lots that charge even less.)

BWI is quite a bit cheaper than Reagan National or Dulles, though those two airports are still relatively inexpensive. Dulles was the 12th-cheapest airport for parking, averaging $30 for terminal parking and $10 for long term. Reagan National was 14th cheapest overall, averaging $25 for terminal parking and $17 for long term. Of course, Reagan has the nice advantage of being Metro accessible as well.

One downside to BWI is its lack of Metro accessibility, though it is possible to reach the airport via MARC train for about $6 from Union Station in D.C.

The most expensive airport to park at? New York’s Laguardia, at $59 a day at the terminal and $39 for long-term. Boston’s Logan airport charges less for long-term parking ($26) but a whopping $70 if you want to park close.

Do you take parking fees into account when selecting an airport?

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