Sell a House With Open Permits in Suffolk County
In Suffolk County, building permits and certificates of occupancy come from the town or village, not the county. Here's how open permits and missing COs get sorted out, and how selling as-is works.
Who handles permits in Suffolk County
New York law has each village, town and city enforce the state building code.[1] Suffolk County’s own business guide says building permits in unincorporated areas are handled by each town’s Building and Zoning Departments, and that a certificate of occupancy (CO) should be requested once a renovation is finished.[2]
So the office that matters is the one for the town your house is in: Babylon, Brookhaven, East Hampton, Huntington, Islip, Riverhead, Shelter Island, Smithtown, Southampton or Southold. Incorporated villages run their own. The Town of Smithtown’s Building Department, for example, doesn’t take applications for projects in the Village of the Branch, Nissequogue or Head of the Harbor.[3]
Why open permits matter when you sell
- The Town of Babylon says work done without a permit can be legalized by applying for a building permit, which leads to a CO, and that homeowner’s insurance and mortgage companies usually require a CO when a home is sold, bought or refinanced. If the work isn’t up to code, repairs are sometimes needed first.[4]
- The Town of Huntington checks a property for expired permits and unpermitted work when it reviews a new application, and it won’t issue a CO for that project until those are legalized. Work that started or finished before a permit was issued pays three times the normal application fee.[5]
How six towns handle it
| Town | What to know |
|---|---|
| Huntington | The Building & Housing Division (Town Hall, Room 115, 100 Main Street, (631) 351-2821) issues permits and COs. Its online Site History Summary shows a property’s permit and CO applications. An original letter-in-lieu of a CO costs $200, and a departmental search costs $30.[5] |
| Brookhaven | A building permit is generally valid for 365 days, and applications stay active for 24 months. Some older structures can get a Certificate of Existing Use, including mainland houses built before 1959. Owners can ask online to void an issued permit.[6] |
| Islip | A residential compliance permit covers structures built more than 4 years ago without a permit, permits past their maximum renewals and unpermitted accessory apartments. It expires after one year and can’t be renewed. The Records Section closes out permits with a certificate of occupancy or compliance (631-224-5470).[7] |
| Smithtown | A permit is good for one year and can be renewed once. The Building Department will search its records to see whether every permit on a property has its certificate. For a house built before permits were required in 1947, owners can request a History Letter (Letter in Lieu).[3] |
| Southampton | A Pre-Existing Certificate of Occupancy covers buildings and uses that existed before zoning took effect on October 14, 1957. It takes an original survey, sworn affidavits, floor plans and a final inspection.[8] |
| Babylon | Since February 2026, every Building Department application goes through the town’s Online Permit Center, which also tracks its status.[4] |
Selling as-is with open permits
Mike Plactere buys Suffolk County houses with open permits or missing certificates of occupancy. You don’t legalize anything or chase old permits first. We buy the house as it is and deal with the town ourselves afterward.
We’ve done it before. At a house we bought in Mastic Beach, a shed sat too close to the house under Town of Brookhaven rules and had to be legalized. It was too heavy to move, so we took it down.
- A cash offer within 24 hours of seeing the house, with the math behind it.
- No fees or commissions, and we cover the standard seller-side closing costs.
- You pick the closing date.
Sources
- New York Executive Law § 381 and § 372.
- Suffolk County, "Starting a Business."
- Town of Smithtown, Building Department FAQ.
- Town of Babylon, Building Department.
- Town of Huntington, Building & Housing, expired permits and unpermitted work, building fee schedule and Land Management Information.
- Town of Brookhaven, Building Construction, Certificate of Existing Use and Void Building Permit request.
- Town of Islip, residential compliance permit requirements and Building Division.
- Town of Southampton, Pre-Existing Certificate of Occupancy requirements.
Frequently asked questions
Can I sell a Suffolk County house with open permits?
Yes. We buy Suffolk County houses with open permits or no certificate of occupancy as-is, and we deal with the town after we buy.
Who issues certificates of occupancy in Suffolk County?
The town or village where the house is, not the county. Suffolk County's business guide says each town's Building and Zoning Departments handle building permits in unincorporated areas.
What's a letter in lieu of a certificate of occupancy?
Some towns issue one for houses built before permits were required. Smithtown's History Letter covers houses built before 1947, and Huntington charges $200 for an original letter-in-lieu.
Do I have to legalize everything before I sell?
Not to sell to us. On a regular sale, the Town of Babylon notes that insurance and mortgage companies usually require a certificate of occupancy.