Sudbury

Middlesex County · Pop. 18,934

A

Sudbury has approved 3 of 3 ADU applications (100% approval rate) and has 4 of 10 bylaw provisions consistent with state law.

Some bylaw provisions aren’t yet consistent with state law, but permits are still being approved. State law overrides inconsistent local rules.
How active is your town?
1.6
per 10K residents0.8x state average
Sudbury
1.6
State avg
2.0

Based on 3 approved ADU applications and 18,934 residents

Permits

100%approval rateShare of 2025 applications approved in 2025
3 approved0 denied0 pending

3 applications since the ADU law took effect in Feb 2025

Oakwood Ave
Issued
Internal$50,000
Willow Rd
Issued
Detached$297,000
Fox Run
Issued
Attached$300,000

Bylaw Consistency

4 / 10
provisions consistent with Chapter 150

Sudbury’s bylaw was partially gutted by the AG in October 2025 — 3 provisions deleted, 1 partially struck. The surviving ‘architecturally harmonious’ requirement is a gray area. Confirm with the building department which version of the bylaw they’re enforcing.

Provision-by-provision analysis available

We've mapped 10 provisions in Sudbury against Chapter 150. See which specific bylaw sections appear inconsistent with state law.

See full compliance analysis

Cost Snapshot

Low
$50,000
Median
$297,000
High
$300,000

Based on 3 permitted ADU projects in Sudbury

Try the full cost estimator

ADU Impact on Housing Production

In 2024, Sudbury issued 10 total residential building permits. In the first year of the ADU law, 3 ADU permits were approved — equivalent to 30% of prior-year housing production.

2024 Building Permits
10
2025 ADU Approvals
3

Source: Census Bureau (2024) via UMass Donahue Institute; EOHLC ADU Survey (2025)

How Sudbury Compares

Next Steps

Sources: EOHLC ADU Survey 2025. Individual permit records from municipal building department. Population estimates from 2024 Census ACS.

Disclaimer: ADU Pulse provides data for informational purposes only. It does not constitute legal, financial, or construction advice.Bylaw consistency analysis reflects our interpretation of public records and may not reflect the most current local amendments.

See methodology for details on data collection, scoring, and consistency analysis.