ADU Rules in Boston, MA — 2026 Guide
Check if your Boston property qualifies for an ADU in 20 seconds
Boston ADU Rules at a Glance
Boston is considered ADU-friendly. Here are the key regulations.
- MA Affordable Homes Act (2024) allows ADUs by right statewide on single-family lots.
- Boston permits ADUs up to 900 sqft under the new state framework.
- No owner-occupancy requirement under the state law.
- ADU cannot be used as a short-term rental under 30 days.
What ReadyPermit Checks for Boston Properties
Enter any Boston address and get an instant ADU feasibility analysis covering:
Zoning Compliance
Verify your Boston lot is zoned for ADU construction under current MA and local rules.
Setbacks & Coverage
Check required setbacks, lot coverage limits, and height restrictions for your specific parcel.
ADU Size Limits
Calculate the maximum ADU square footage allowed based on your lot size and primary dwelling.
Permit Requirements
Understand what permits and approvals Boston requires before you can break ground.
Flood & Hazard Zones
Identify if your property falls in a flood zone, fire zone, or other hazard overlay.
Lot & Parcel Data
Pull parcel boundaries, lot dimensions, and existing structures from county records.
Check Your Boston Property Free
Enter your address below. In under 20 seconds you will know if your Boston lot qualifies for an ADU — no phone calls, no waiting.
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