According to a year-end traffic report released by the Houston Airport System (HAS), George Bush Intercontinental Airport welcomed 42.9 million passengers (+8%) and William P Hobby a record 12 million (+1.8%).
HAS claims that the figures, a 4% upturn on 2014, repesent an "unprecedented total in the history of the two facilities".
"Houston's vibrant economy and diverse population continue to spark unprecedented growth at both our commercial airports," says Houston Mayor, Sylvester Turner.
"We've seen historic passenger totals in Houston on a regular basis, followed by a string of new international air carriers and all of this growth and activity is vital to the future success of the entire region."
At George Bush Intercontinental Airport, domestic traffic increased by almost a million passengers in 2015, rising to 32.3 million by the end of the year.
While the number of international passengers increased by an impressive 8%, rising from 9.8 million in 2014 to 10.6 million in 2015.
In 2015, Houston Airports welcomed seven new foreign flag carriers and also expanded service to international destinations from existing carriers.
At William P Hobby Airport, an all-time record in passenger totals was set for the sixth consecutive year, with the airport reaching the 12 million mark for the first time in its history.
Demand for travel from Hobby is growing at a steady pace and has increased more than 30% in 10 years – an increase of nearly 3 million passengers since 2006.
The airport also welcomed international flights for the first time in more than 40 years when Southwest Airlines began offering service to destinations in Latin America and the Caribbean in 2015.
"Houston's status as a true global gateway city continues to grow stronger as a result of these record-setting passenger totals," says HAS director, Mario Diaz.
"Houston is one of only two municipalities in the United States to offer passengers a choice between two international airports, and we are the only city in the western hemisphere to offer non-stop flights to all six inhabited continents."