ADU · Erie County
Can you build an ADU in Amherst, NY?
Town of Amherst has 25 districts. 15 districts prohibit ADUs, 10 allow them with occupancy restrictions. Check your address to confirm the district that applies to your parcel:
What the Amherst code indicates by district
The table below shows how each district treats ADUs, alongside the lot and setback standards that govern a second unit. District boundaries and conditions vary, so treat this as a starting point and confirm the district that applies to your parcel.
| District | Min lot | Setbacks F / S / R | Max height | ADU |
|---|---|---|---|---|
| Rural Residential District | 3 ac | 50 / - / - ft | 35 ft | Occupancy restricted |
| Suburban Agricultural District | 1 ac | 50 / - / - ft | 35 ft | Occupancy restricted |
| Residential District One | 0.5 ac | 30 / 8 / 35 ft | 35 ft | Occupancy restricted |
| Residential District Two | 0.264 ac | 30 / 8 / 35 ft | 35 ft | Occupancy restricted |
| Residential District Three | 0.194 ac | 30 / 5 / 30 ft | 35 ft | Occupancy restricted |
| Cluster Residential District Three-A | 0.115 ac | 25 / - / 30 ft | 35 ft | Occupancy restricted |
| Traditional Single-Family Residential District | 0.103 ac | 25 / 5 / 25 ft | 35 ft | No |
| Residential District Four | 0.134 ac | 30 / 8 / 30 ft | 35 ft | Occupancy restricted |
| Multifamily Residential District Four-A | 0.138 ac | 25 / 5 / 20 ft | 35 ft | Occupancy restricted |
| Multifamily Residential District Five | 0.083 ac | — | 35 ft | Occupancy restricted |
| Multifamily Residential District Six | 0.138 ac | 25 / - / - ft | 35 ft | Occupancy restricted |
| Multifamily Residential District Seven | 0.138 ac | — | — | No |
| Manufactured Home Residential District Eight | 0.092 ac | 30 / 15 / 15 ft | — | No |
| Office Building District | — | 20 / - / - ft | — | No |
| Neighborhood Business District | 1 ac | - / 10 / 15 ft | 30 ft | No |
| General Business District | — | 20 / - / - ft | 65 ft | No |
| Commercial Service District | 1 ac | 20 / 10 / 10 ft | 40 ft | No |
| Motor Service District | — | 20 / 10 / 25 ft | 65 ft | No |
| Shopping Center District | 10 ac | 25 / 50 / 50 ft | 65 ft | No |
| Research and Development District | 1 ac | 20 / - / - ft | 65 ft | No |
| Science Technology District | 2 ac | 20 / - / - ft | 45 ft | No |
| General Industrial District | 1 ac | 20 / - / - ft | 65 ft | No |
| AG Agricultural District | 5 ac | 50 / 30 / 30 ft | 35 ft | No |
| TND Traditional Neighborhood Development District | — | - / 15 / 15 ft | 50 ft | No |
| LW-1 Live-Work District 1 | — | 25 / 5 / 25 ft | 35 ft | No |
ADUs vs. short-term rentals in Amherst
Short-term rentals allowed with registration for Town of Amherst. A short-term rental requires Town registration. § 44-3 of Chapter 44, Rental Unit Registration, makes it unlawful to let a dwelling unit unless the owner has first obtained EITHER a short-term rental dwelling unit registration certificate OR an ordinary rental dwelling unit registration — so the short-term case has its own certificate. § 44-2 defines SHORT TERM RENTAL, and § 44-7 sets the registration term. The requirement is outside the zoning chapter. New York State's 2025 short-term rental registry (Ch. 99 of the Laws of 2025) separately requires every host statewide to register the unit regardless of local law. Confirm with Town of Amherst at (716) 631-7080 before listing. These are separate questions from whether you can build an ADU — a unit you're allowed to add isn't automatically one you're allowed to rent nightly, so check both.
Good to know
- Residential lot minimum0.083–5 ac — an ADU still has to fit the district's lot and setback envelope.
- UtilityNational Grid territory.
- Building dept(716) 631-7080
- Last reviewed2026-08-06
ADU FAQ — Amherst, NY
Are ADUs allowed in Amherst, NY?
Town of Amherst has 25 districts. 15 districts prohibit ADUs, 10 allow them with occupancy restrictions. Check your address with the free ADU checker, or confirm with the building department at (716) 631-7080.
Do I need a special permit for an ADU in Amherst?
No district in Town of Amherst requires a special-use permit for an ADU - 15 districts prohibit ADUs, 10 allow them with occupancy restrictions. Site-plan review or a building permit may still apply.
Can I use an ADU as a short-term rental in Amherst?
Short-term rentals allowed with registration for Town of Amherst. ADU occupancy and short-term-rental rules are separate: an ADU you can build isn't automatically one you can rent nightly. Confirm both before you count on STR income.
What an ADU costs to build in Amherst
Permission is one question and budget is another. An 800 sq ft accessory unit here runs roughly $200k–260k at a standard finish, and the per-square-foot rate comes in above a full house because the kitchen, bath, panel and heating plant cost the same either way. See the full cost to build an ADU in Amherst, priced by size.
More on Amherst: Full zoning for new construction · ADU build cost · House build cost · All Erie County towns
ADU information for Town of Amherst is compiled from the municipal code (last reviewed 2026-08-06) and provided for decision-support only — not legal or architectural advice. ADU eligibility, size, owner-occupancy and permit conditions vary by district and often carry exceptions; verify with the building department at (716) 631-7080 before relying on any answer. Source: Offsite / Aldo zoning dataset, municipalData.js.