Portland International Airport (IATA: PDX, ICAO: KPDX, FAA LID: PDX) is a joint civil–military airport and the largest airport in the U.S. state of Oregon, accounting for 90% of the state's passenger air travel and more than 95% of its air cargo. It is within Portland's city limits just south of the Columbia River in Multnomah County, 6 miles (10 kilometers) by air and 12 mi (19 km) by highway northeast of downtown Portland. Portland International Airport is often referred to by its IATA airport code, PDX. The airport covers 3,000 acres (1,214 ha) of land.

Portland International Airport has direct flights to cities throughout the United States and in several other countries, including Canada, Mexico, Germany, United Kingdom, the Netherlands, and Iceland. The airport is a hub for Alaska Airlines. It also has a maintenance facility for Alaska Air subsidiary Horizon Air. General aviation services are provided at PDX by Atlantic Aviation. The Oregon Air National Guard has a base on the southwest portion of the airport property grounds, and is also the host unit of the 142nd Fighter Wing (142 FW), which operates the F-15 Eagle. Local transportation includes the MAX Red Line light rail, which takes passengers between PDX and downtown Portland, as well as farther west to Beaverton. There is also Interstate 205, which connects to southwestern Washington (north from PDX) along with many suburbs of Portland (south from PDX).