Pittsfield is the largest city in and the county seat of Berkshire County, Massachusetts, United States. It is the principal city of the Pittsfield, Massachusetts Metropolitan Statistical Area which encompasses all of Berkshire County. Its area code is 413. Its ZIP code is 01201 (01202 and 01203 are ZIP codes for Pittsfield post office boxes only). The population was 45,793 at the 2000 census, and it continues to be one of the population centers of Western Massachusetts, although the population has declined in recent decades. In 2005, Farmers Insurance ranked Pittsfield 20th in the United States as “Most Secure Place To Live” among small towns with fewer than 150,000 residents. In 2006, Forbes ranked Pittsfield as number 61 in its list of Best Small Places for Business. In 2008, Country Home Magazine ranked Pittsfield as #24 in a listing of "green cities" East of the Mississippi. In 2009, the City of Pittsfield was chosen to receive a 2009 Commonwealth Award, Massachusetts' highest award in the arts, humanities, and sciences.