MA · State directory

Massachusetts ADU rules

Official accessory dwelling unit regulations for 7 jurisdictions in Massachusetts, plus statewide law.

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We have read the ordinances for 2 Massachusetts cities and lined them up side by side: detached vs internal, size limits, owner occupancy, and approval process.

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Statewide ADU law

Massachusetts has state-level ADU legislation that applies across local jurisdictions. Local rules below may add requirements on top of state law.

Cities

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