Southampton Airport (IATA: SOU, ICAO: EGHI) is an international airport located in both Eastleigh and Southampton, Hampshire, in the United Kingdom. The airport is located 3.5 nautical miles (6.5 km; 4.0 mi) north-north-east of central Southampton. The southern tip of the runway lies within the Southampton unitary authority boundary with most of the airport, including all of the terminal buildings, within the Borough of Eastleigh.

The airport handled nearly two million passengers during 2016, an 8.8% increase compared with 2015, making it the 18th busiest airport in the UK. Southampton Airport has a CAA Public Use Aerodrome Licence (Number P690) that allows flights for the public transport of passengers or for flying instruction. The airport is owned and operated by AGS Airports which also owns and operates Aberdeen and Glasgow Airports. It was previously owned and operated by Heathrow Airport Holdings (formerly known as BAA).

Up to March 2020, 95% of the flights from Southampton were operated by Flybe. However, the airline went into administration on 5 March 2020 with all flights cancelled. When Flybe was purchased and relaunched, it was announced that they would start serving Southampton Airport from the 23 July 2022. The reincarnated Flybe ultimately ceased operations nine months after its relaunch.