Baltimore/Washington International Thurgood Marshall Airport continues to post record-breaking numbers of passengers flying through its terminals, airports officials said Monday.

The airport, one of three major hubs serving the Washington region, has been buoyed by budget airlines Southwest Airlines and AirTran Airways.

Southwest carried 1.09 million passengers out of the total 1.99 million to travel through BWI’s gates in October. The airline recently announced plans to expand its presence at the airport in the spring with two new routes to Charleston and Greenville-Spartanburg in South Carolina.

AirTran Airways, the second leading carrier at BWI, reported 298,463 passengers for October, BWI officials said.

Overall passenger traffic has increased at BWI for 16 of the past 17 months over similar months’ numbers, airport officials said, with only February falling short when record snowstorms waylaid flights nationwide.

July, the height of the summer tourism season, holds the record for busiest month ever at the airport. This October beat the October 2009 tally, the prior record for that month, by 7.2 percent.