{"publisher":"Massachusetts Executive Office of Housing and Livable Communities","source":"https://www.mass.gov/info-details/accessory-dwelling-unit-tracker","download":"https://www.mass.gov/files/csv/2026-08/ADUSurvey2026Midyear_DownloadableComposite.csv","sha256":"aebd9f22bce2d5f42f6c9022eb556fef9685627da45c63c7749f187e2cc6e04c","retrieved":"2026-09-08","period":"2025 and January–June 2026","municipalities":351,"limitations":"Voluntary municipality survey; incomplete responses and reporting periods. Null means not reported, not zero. Approvals, occupancy certificates and applications are different measures. Boston has separate zoning authority. No construction costs are provided."}