Matanuska-Susitna Borough, Alaska

Matanuska-Susitna Borough
Borough
Ruth Glacier
Flag Seal
Location within the U.S. state of Alaska
Alaska's location within the U.S.
Coordinates: 62°24′N 149°35′W / 62.4°N 149.58°W / 62.4; -149.58
Country	United States
State	Alaska
Incorporated	January 1, 1964[1][2]
Named for	Matanuska River and Susitna River
Seat	Palmer
Largest CDP	Knik-Fairview
Area
• Total	25,258 sq mi (65,420 km2)
• Land	24,608 sq mi (63,730 km2)
• Water	650 sq mi (1,700 km2)  2.6%
Population  (2020)
• Total	107,801
• Estimate  (2022)	113,325
• Density	4.3/sq mi (1.6/km2)
Time zone	UTC−9 (Alaska)
• Summer (DST)	UTC−8 (ADT)
Congressional district	At-large
Website	www.matsugov.us

Matanuska-Susitna Borough (often referred to as the Mat-Su Borough) is a borough located in the U.S. state of Alaska. Its borough seat is Palmer, and the largest community is the census-designated place of Knik-Fairview. As of the 2020 census, the borough's population was 107,801.^[3]

The borough is part of the Anchorage Metropolitan Statistical Area, along with the municipality of Anchorage on its south.

The Mat-Su Borough is so designated because it contains the entire Matanuska and Susitna Rivers. They empty into Cook Inlet, which is the southern border of the Mat-Su Borough. It is one of the few agricultural areas of Alaska.