Boston, MA Zoning Overlays & Bonuses: Density Bonus Law (2026)
Key Facts
- Bonus amount
- +1.0 floor area ratio
- Eligible areas
- PDA I, VI, VII, and X only
- Baseline FAR range
- 2.0 (PDA VII) to 5.0 (PDA VI)
- Mixed-use treatment
- Bonus pro-rated above ground floor
- Approval path
- Article 80 PDA Development Plan review
- Governing article
- Zoning Code Article 62, Charlestown District
Summary
Boston's Zoning Code grants a residential density bonus in the Charlestown Neighborhood District: Section 62-21 adds 1.0 to the maximum floor area ratio for residential projects in Planned Development Areas I, VI, VII, and X. Mixed-use buildings with non-residential floors above ground level get the bonus pro-rated. The baseline FAR these bonuses build on, set in Table 2, ranges from 2.0 to 5.0 depending on the PDA.
Section 62-21 - Residential Density Bonus for Planned Development Areas. Projects containing a residential use in PDA I, PDA VI, PDA VII, and PDA X are eligible for a 1.0 increase to the maximum FAR for the area.
For projects containing a mix of residential and non-residential uses above the ground floor, the residential FAR bonus is pro-rated according to the equation shown in this Section 62-21.
Full Breakdown
Boston zones Charlestown under Zoning Code Article 62, and Section 62-21 layers a residential density bonus onto the Planned Development Area (PDA) framework created by Section 62-20. 0 in PDA VI, along with maximum building heights and minimum permeable lot area. 0 FAR increase, but only for projects with a residential use sited in PDA I, PDA VI, PDA VII, or PDA X. 0 in PDA VII. The remaining six PDAs in the district (II, III, IV, V, VIII, and IX) are not listed in Section 62-21 and receive no residential FAR bonus under this provision.
0 rate; instead it is pro-rated according to the equation set out in Section 62-21, scaling the extra floor area to the residential share of the upper floors. Ground-floor retail or commercial space does not by itself reduce the bonus, since the pro-ration only reaches uses placed above the ground floor. The bonus is not self-executing: Section 62-22 requires that PDA Development Plans, PDA Master Plans, and Proposed Projects in these areas go through Article 80 Planned Development Area Review before a project can claim the extra FAR, which in practice means Boston Planning & Development Agency approval of a Development Plan that specifies the bonus square footage.
Violations & Fines
The density bonus is not a right that comes with a penalty structure; it is granted or withheld through project review. Section 62-22 channels every PDA Development Plan, Master Plan, and Proposed Project through Article 80 Large Project Review, so a developer who builds beyond the baseline FAR in Table 2 without an approved Development Plan reflecting the Section 62-21 bonus is building outside the as-of-right envelope and risks an Inspectional Services Department stop-work order or permit denial.
Frequently Asked Questions
Which Planned Development Areas get Boston's Charlestown density bonus?
Does a mixed-use building with ground-floor retail still qualify for the full 1.0 FAR bonus?
Who approves a project claiming the density bonus?
What is the baseline FAR before the bonus applies in these PDAs?
Sources & Official References
Other rules in Boston
Compare Boston to another location·View the Massachusetts zoning overlays & bonuses overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.