Somerville building & ADU permits
Recent permit activity, updated continuously.
Somerville is a dense city just northwest of Boston. Under Massachusetts' 2024 Affordable Homes Act, ADUs are now allowed by right across the state. The city publishes its building permits under the ODbL, so Igni credits the City of Somerville's SomerStat office wherever the data appears.
Igni is tracking 434 residential and building permits in Somerville, MA — including 6 classified accessory-dwelling-unit (ADU) filings. The most active ZIP is 02144. The most recent filing Igni tracked was Nov 3, 2026. All records come from data.somervillema.gov (Socrata), an official government open-data feed, and are refreshed continuously.
434
Permits tracked
6
ADU permits
4
Distinct ZIP codes
Nov 3, 2026
Newest permit
Recent permits
A sample of the freshest permits in this jurisdiction — ZIP and city only (no street addresses).
| ZIP | Permit type | ADU type | Valuation | Applied |
|---|---|---|---|---|
| 02144 | Residential | — | $237,000 | Jul 31, 2026 |
| 02144 | Residential | — | $250,000 | Aug 21, 2026 |
| 02144 | Residential | — | $400,000 | Sep 22, 2026 |
| 02144 | Residential | — | $4,731 | Sep 18, 2026 |
| 02144 | Residential | — | $26,469 | Sep 28, 2026 |
| 02144 | Residential | — | $8,500 | Oct 4, 2026 |
| 02143 | Residential | — | $33,624 | Oct 7, 2026 |
| 02145 | Residential | — | $510,200 | May 22, 2026 |
| 02145 | Residential | Garage conversion | $100,000 | May 31, 2026 |
| 02143 | Residential | — | $25,000 | Apr 7, 2026 |
| 02144 | Residential | — | $34,486 | Aug 5, 2026 |
| 02143 | Commercial | — | $0 | Sep 2, 2026 |
| 02145 | Residential | — | $15,800 | Sep 15, 2026 |
| 02143 | Residential | — | $39,600 | Sep 30, 2026 |
| 02144 | Residential | — | $26,600 | Oct 4, 2026 |
| 02144 | Residential | — | $6,000 | Oct 2, 2026 |
| 02145 | Residential | — | $16,500 | May 22, 2026 |
| 02145 | Residential | — | $1,250,000 | Apr 19, 2026 |
| 02145 | Residential | — | $634,500 | Mar 25, 2026 |
| 02143 | Residential | — | $949,000 | Apr 11, 2026 |
Top ZIP codes by recent activity
ADU types in the recent set
Permit activity in Somerville
Igni counted 1,886 permits issued in Somerville over the last 12 months (Nov 2025 – Oct 2026) — roughly flat (−0.7%) on the 1,900 in the 12 months before. The forecast expects about 942 over the next 6 months.
Forecast: trailing mean, typical error ±10% in backtests one to six months ahead. How we forecast
| Permit type | Last 12 months | Year over year | Forecast, next 6 months |
|---|---|---|---|
| All permits | 1,886 | Flat (−0.7%) | ≈ 942 |
| Residential building | 1,698 | Flat (+0.5%) | ≈ 852 |
| Commercial building | 188 | Down 10.5% | ≈ 96 |
| Trade (electrical, plumbing, mechanical) | 0 | — | — |
| ADU | 21 | — | — |
Monthly figures
| Month | Permits | 10th–90th percentile |
|---|---|---|
| Nov 2023 | 124 | — |
| Dec 2023 | 137 | — |
| Jan 2024 | 173 | — |
| Feb 2024 | 150 | — |
| Mar 2024 | 122 | — |
| Apr 2024 | 160 | — |
| May 2024 | 142 | — |
| Jun 2024 | 159 | — |
| Jul 2024 | 208 | — |
| Aug 2024 | 162 | — |
| Sep 2024 | 189 | — |
| Oct 2024 | 201 | — |
| Nov 2024 | 167 | — |
| Dec 2024 | 160 | — |
| Jan 2025 | 133 | — |
| Feb 2025 | 108 | — |
| Mar 2025 | 124 | — |
| Apr 2025 | 177 | — |
| May 2025 | 133 | — |
| Jun 2025 | 160 | — |
| Jul 2025 | 165 | — |
| Aug 2025 | 163 | — |
| Sep 2025 | 192 | — |
| Oct 2025 | 218 | — |
| Nov 2025 | 146 | — |
| Dec 2025 | 196 | — |
| Jan 2026 | 149 | — |
| Feb 2026 | 86 | — |
| Mar 2026 | 167 | — |
| Apr 2026 | 149 | — |
| May 2026 | 154 | — |
| Jun 2026 | 158 | — |
| Jul 2026 | 160 | — |
| Aug 2026 | 184 | — |
| Sep 2026 | 156 | — |
| Oct 2026 | 181 | — |
| Nov 2026 (forecast) | ≈ 157 | 105–188 |
| Dec 2026 (forecast) | ≈ 157 | 106–179 |
| Jan 2027 (forecast) | ≈ 157 | 91–179 |
| Feb 2027 (forecast) | ≈ 157 | 131–178 |
| Mar 2027 (forecast) | ≈ 157 | 147–179 |
| Apr 2027 (forecast) | ≈ 157 | 149–179 |
Counts are permits issued per calendar month as Somerville publishes them to its open-data feed — not a complete census; a change in what the city publishes moves them too. The current month is left out, and the most recent months are provisional. A forecast is a statistical estimate with a range, not a prediction for any project. Informational only.
How long do permits take in Somerville?
Based on 5,655 Somerville permits applied for between Nov 2023 and Aug 2026, the typical (median) permit was issued 30 days after application, and the middle half of permits took 18–71 days. One in ten took longer than 266 days.
| Permit type | Median | Typical range | Permits |
|---|---|---|---|
| All permits | 30 days | 18–71 days | 5,655 |
| Residential building | 29 days | 17–70 days | 5,017 |
| Commercial building | 42 days | 22–93 days | 638 |
| ADU | 144 days | 75–238 days | 42 |
Typical, not guaranteed: individual permits vary with project scope, application completeness and plan-review workload. Days are calendar days from application to issuance; applications still pending are counted as not-yet-issued rather than dropped. Informational only, not legal advice. How we calculate approval times.
Housing law — Massachusetts
Massachusetts legalized accessory dwelling units by right statewide through the Affordable Homes Act (2024); as of February 2025, an ADU up to 900 sq ft is allowed by right in single-family zoning districts in nearly every community, without an owner-occupancy requirement.
The MBTA Communities Act (2021) requires the 177 MBTA-served cities and towns to zone for multifamily housing as of right near transit; the state's highest court upheld the law as constitutional and enforceable in 2025.
Data source
Sourced from data.somervillema.gov (Socrata). ODbL (attribution required; share-alike).
Attribution: © City of Somerville (SomerStat) (ODbL)
Nearby cities — Massachusetts
Learn more about ADUs & building permits
Background reading on accessory dwelling units, building permits, and how Igni turns Somerville permit records into leads.
Somerville permit data — FAQ
Where does Igni get Somerville permit data?
How fresh is Somerville permit data?
How long does it take to get a building permit in Somerville?
Is construction activity growing in Somerville?
Does Somerville allow accessory dwelling units (ADUs)?
Get permit leads — Somerville
Fresh, filterable residential and ADU permit leads from Somerville — delivered before your competitors even know.
Informational only, not legal advice. Headline counts reflect all permits Igni has tracked for this jurisdiction; the table shows recent activity. Housing law changes — verify current statutes before relying on this.