AccessoryDwellingUnitServices ES 📞 (815) 860-2798

Accessory dwelling unit permit cost — Boston, MA

Looking for accessory dwelling unit permit cost in Boston, MA? Call AccessoryDwellingUnit Services for a contact a provider — no obligation. Licensed adu builders serve Boston and the surrounding area, and you'll get straight answers on timing and what affects the price.

Last updated: September 24, 2026

What affects the price

Building an ADU involves several moving parts that shape your total investment. The final figure depends heavily on whether you choose a prefab unit or a custom build from the ground up. Site conditions are another major factor; if your property requires extensive grading, utility trenching, or foundation work, costs will climb. You also have to consider your choice of finishes, like high-end appliances or custom cabinetry. Navigating local permit fees and impact assessments also adds to the total.

Frequently asked in Boston

What are the disadvantages of ADUs?

Building an ADU in Boston often involves complex permitting processes that can take several months to finalize. You may face constraints regarding lot coverage and property setbacks in dense areas like Beacon Hill. Additionally, construction costs can vary significantly based on existing foundation conditions. Talk to a specialist to weigh these challenges against the long-term benefits for your Boston home.

How much does an ADU cost in Massachusetts?

Total costs depend on site preparation, material quality, and whether you choose a detached structure or an internal conversion. Boston labor rates and local permit fees impact the final tally significantly. A site-specific assessment is necessary to provide an accurate breakdown for your property. Call us now to get a professional quote tailored to your unique Boston backyard space.

What are the rules for ADUs in California?

While our local pros focus on Massachusetts, they are well-versed in the specific bylaws governing Boston accessory dwellings. Rules in other states like California do not apply to your local project. You should ignore out-of-state regulations and focus on the current Boston zoning ordinances. Contact us to learn exactly what is permitted on your specific lot today.

Is ADU allowed in Maryland?
What are the rules for ADU in California?

That specific grant program is exclusive to California homeowners and does not apply to projects located in Boston. You should focus on local financing options or home improvement loans available within the state of Massachusetts. Avoid relying on out-of-state incentives when planning your budget. Call us now to discuss how to structure your project costs effectively for your Boston property.

Also serving nearby: Quincy · Cambridge · Lynn · Newton · Brockton

All cities in Massachusetts →

More on this: HUD ADU resources — ADU policy and financing research.

Service area details

653,833residents
13,525per sq mile
8ZIP codes served

Serving all of Boston — population 653,833; about 13,525 residents per square mile across 48.3 sq mi. ZIP codes covered include 02108, 02109, 02110, 02111, 02112, 02113, 02114, 02115.

Neighborhoods served in Boston: Beacon Hill, Back Bay, South End, Jamaica Plain, Dorchester, Charlestown — and every surrounding area.

Areas we serve

Browse by state, then city.

Alabama (4)
Alaska (1)
Arizona (9)
Arkansas (1)
California (32)
Colorado (4)
District of Columbia (1)
Florida (11)
Georgia (3)
Hawaii (1)
Idaho (1)
Illinois (2)
Indiana (1)
Iowa (1)
Kansas (2)
Kentucky (2)
Louisiana (3)
Massachusetts (2)
Michigan (2)
Minnesota (2)
Missouri (3)
Nebraska (2)
Nevada (3)
New Jersey (2)
New Mexico (1)
New York (3)
North Carolina (4)
Ohio (5)
Oklahoma (2)
Oregon (2)
Pennsylvania (2)
Rhode Island (1)
South Dakota (1)
Tennessee (5)
Texas (17)
Utah (1)
Virginia (5)
Washington (3)
Wisconsin (2)