Spencer Municipal Airport (IATA: SPW, ICAO: KSPW, FAA LID: SPW), also known as Northwest Iowa Regional Airport, is a public airport located three miles (5 km) northwest of the central business district of Spencer, a city in Clay County, Iowa, United States. It is owned by the City of Spencer.

The airport is used by charter airlines including Plane Master Services and Nova Air. It has been served by Great Lakes Airlines. The airline was named after the nearby Iowa Great Lakes. The airline has since ceased operations.