Building Permits in Boston

Boston requires a building permit for most construction, alteration, and repair work that affects structural, electrical, plumbing, or mechanical systems. Permits are issued by the ISD (Inspectional Services Department), the city agency responsible for building permits, housing inspections, and code enforcement at 1010 Massachusetts Avenue.

Boston enforces the Massachusetts State Building Code (780 CMR), a statewide code based on the 2021 International Building Code (IBC) and 2021 International Residential Code (IRC). Massachusetts is a state-mandatory building code jurisdiction — the commonwealth sets a single code that all municipalities enforce, so Boston does not adopt its own local building code amendments beyond what 780 CMR already allows.

The Key Split: ISD vs. BPDA

Boston's development process involves two separate agencies with distinct roles. Understanding this split is the most important thing for anyone planning a project in Boston.

ISD (Inspectional Services Department) is the building department. ISD reviews applications for code compliance under 780 CMR, issues building permits, and conducts all construction inspections. For most straightforward residential and commercial projects that comply with existing zoning, your interaction is primarily with ISD.

BPDA (Boston Planning & Development Agency) is the city's planning and development authority. The BPDA administers Article 80 of the Boston Zoning Code — a design and impact review process that applies to larger projects and certain categories of development. Article 80 has two tracks:

• Large Project Review (Article 80B) — applies to projects over 20,000 square feet or more than 15 dwelling units (approximately). These projects undergo extensive public review, traffic and infrastructure impact analysis, and design review before receiving BPDA approval.
• Small Project Review (Article 80E) — a streamlined review track for smaller projects that still require BPDA design oversight.

If your project triggers Article 80 review, you must obtain BPDA approval before ISD will issue a building permit. The BPDA and ISD processes run sequentially, not in parallel, which is why large projects in Boston have longer overall timelines than the building permit review alone might suggest.

For projects that conform to existing zoning and fall below Article 80 thresholds, you deal with ISD only.

Short-Form vs. Long-Form Permits

ISD divides building permit applications into two categories:

Short-Form Permits cover minor alterations, repairs, or replacements that do not change the structure or use of a building — for example, opening a wall for minor electrical or plumbing work, repairing a deck, or replacing roofing materials in kind. The fee is $20 plus $10 per $1,000 of estimated project cost. Owner-occupants of 1–2 family homes may self-perform work on short-form permits.

Long-Form Permits are required for major alterations, structural changes, new construction, additions, demolition, changes of use, and any work that materially changes the structure or occupancy of a building. Long-form applications require professionally stamped design plans, a certified plot plan from a licensed surveyor, detailed work descriptions, cost estimates, and contractor insurance and licensing documentation. The fee is $50 plus $10 per $1,000 of estimated project cost.

Both permit types must be applied for through the ISD online portal before any work begins. The permit must be used within six months of issuance.

When You Need a Permit

You generally need a Boston building permit for:

• New construction, additions, and accessory structures (including ADUs)
• Structural alterations, load-bearing wall changes, and foundation work
• Electrical, plumbing, and mechanical (HVAC) changes
• Reroofing and window or door openings in exterior walls
• Swimming pools, most retaining walls above a height threshold, and certain fences
• Change of use or occupancy of any space
• Demolition of any habitable structure

Minor cosmetic work — painting, floor coverings, cabinetry without plumbing or electrical changes — is typically exempt. When in doubt, contact ISD before starting work.

Permit Costs

Boston's ISD building permit fees are based on estimated project valuation:

• Short-form permit — $20 application fee + $10 per $1,000 of project cost
• Long-form permit — $50 application fee + $10 per $1,000 of project cost
• Trade permits (electrical, plumbing, mechanical) — separate permit fees apply for each trade
• Demolition permits — separate fee schedule

Do not rely on third-party fee estimates. Verify the current fee schedule directly with ISD at 617-635-5300 or [email protected] before budgeting.

Typical Timeline

Review times vary with ISD workload and the completeness of your submission. Incomplete applications are a leading cause of delay.

The Process

1. Determine your permit type: Confirm whether your project needs a short-form or long-form permit, and whether it triggers Article 80 or Landmarks Commission review
2. BPDA review first (if required): If your project triggers Article 80, obtain BPDA approval before proceeding to ISD
3. Landmarks Commission (if applicable): For properties in historic districts, obtain Boston Landmarks Commission approval for exterior work
4. Create an ISD portal account: Register at the Inspectional Services online portal (onlinepermitsandlicenses.cityofboston.gov/isdpermits/)
5. Prepare documents: For long-form permits — stamped plans, certified plot plan, work description, cost estimate, contractor license and insurance, worker's compensation affidavit, and site safety plan
6. Submit and pay fees: Apply online or in person at 1010 Massachusetts Ave, 5th Floor; fees are due upfront
7. Plan review: ISD reviews for compliance with 780 CMR; complex projects may require review by external agencies (Parks, Fire, Zoning)
8. Corrections: Respond to review comments and resubmit until approved
9. Permit issuance: Receive permit; work must begin within six months
10. Inspections: Schedule required inspections at each construction phase
11. Final inspection: Pass final inspection to close the permit; obtain Certificate of Occupancy if applicable

Inspections

Typical inspection stages for a residential long-form project include:

• Foundation / footings
• Underground plumbing and electrical
• Framing
• Rough plumbing, electrical, and mechanical
• Insulation
• Drywall
• Final building and trade inspections

Schedule inspections through the ISD portal. Inspection requests are generally accommodated within 48 hours of request.

Historic Districts

Properties in Boston's designated historic districts require an additional layer of review by the Boston Landmarks Commission before ISD will issue a permit for exterior alterations. Historic districts include Back Bay, Beacon Hill, Fort Point Channel, Bay Village, St. Botolph Street, and others. Interior work generally does not require Landmarks Commission review unless the building itself is individually landmarked. Factor this additional step and its timeline into your project schedule.

Common Reasons for Denial or Corrections

• Plans do not comply with 780 CMR (Massachusetts State Building Code)
• Missing engineer or architect stamps on required drawings
• No certified plot plan (required for long-form)
• Zoning conflicts — setbacks, height, lot coverage, or use not in conformance
• Article 80 BPDA approval not obtained prior to ISD submission
• Boston Landmarks Commission approval not obtained for historic district properties
• Incomplete contractor licensing or insurance documentation
• Worker's compensation affidavit missing or incorrect

Official Sources

All permit applications go through the ISD online portal at onlinepermitsandlicenses.cityofboston.gov/isdpermits/. To check the status of an issued permit, use the permit finder at permitfinder.boston.gov. For questions, contact ISD at 617-635-5300 or [email protected]. See the sources listed in the frontmatter for direct links to ISD, the permitting guides, and the Boston Municipal Code.

Disclaimer: This guide summarizes publicly available information from official City of Boston sources and is provided for general orientation only. It does not constitute legal or engineering advice. Building code and permitting requirements change — always confirm current rules with the City of Boston Inspectional Services Department and, where applicable, the Boston Planning & Development Agency before submitting plans or starting construction.