The Town of Andover's governing charter was enacted by the Legislature in 1956, and amended in 1974. The Charter authorizes an Open Town Meeting - Select Board - Town Manager form of government.

The Town is overseen by an elected 5-member Select Board, and is administered by an appointed professional Town Manager, who also oversees approximately 20 departments and divisions. Andover's public schools are overseen by an elected 5-member School Committee, and administered by an appointed professional Superintendent.

There are also various appointed boards and committees which have specific responsibilities concerning various aspects of town governance. Town Meeting, which is generally unique to New England, serves as Andover's legislative body. It offers all registered voters of the community the opportunity to participate in the major decisions of the Town. Town Meeting is facilitated by an elected Town Moderator, who also responsible for appointing a nine-member Finance Committee, which in turn is responsible for advising Town Meeting on all matters brought before it.