This is a list of Massachusetts counties, consisting of the 14 Massachusetts counties. Massachusetts has abolished seven of its fourteen county governments, leaving five counties with county-level local government (Barnstable, Bristol, Dukes County, Norfolk, Plymouth) and two, Nantucket County and Suffolk County, with combined county/city government. Vestigial judicial and law enforcement districts still follow the old county boundaries in the counties where county-level government has been disestablished, and the counties are still generally recognized as geographic entities if not political ones.
Eleven other historical counties have existed in Massachusetts, most becoming defunct when their lands were absorbed into the colony of New Hampshire or the state of Maine, both of which were created out of territory originally claimed by Massachusetts colonists. The oldest counties still in Massachusetts are Essex County, Middlesex County, and Suffolk County, created in 1643 with the original Norfolk County which was absorbed by New Hampshire and bears no relation to the modern Norfolk County. When these counties were created, they were a part of the Massachusetts Bay Colony, which would remain separate from the Plymouth Colony and that colony's counties until 1691. Hampden County, created in 1812, is the most recently created county still in Massachusetts, although Penobscot County, Maine bore that distinction until Maine broke off from Massachusetts in 1820. The majority of Massachusetts counties are named in honor of English place names, reflecting Massachusetts' colonial heritage.
The term shire town is the statutory term for the Massachusetts town having a county court and administration offices; a county can have multiple shire towns. County seat is the standard term used in general communications by the Massachusetts government.

Alphabetical list

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Former counties