Selling a House With Open Permits or No Certificate of Occupancy What the building department’s file shows decides how the sale goes.

Where open permits and a missing CO surface in a sale

A house’s building record does not travel with the deed. It sits in the building department’s file, and in a New York sale it is usually looked at in three places.

The house and the file can disagree. A finished basement, a deck, a dormer or a converted garage can be well built and still have no permit or certificate on file. The file is what the buyer’s side reads.

Open permit, no CO, letter in lieu: what each means

What a seller can do about it

Which of these fits depends on what the file shows and what the municipality allows. Your attorney and the building department are the ones to confirm it.

1. Get the file before you list. Ask the building department for the property’s permits, certificates and open items (every department is listed below). The City of Glen Cove puts it plainly: it asks homeowners “to be pro-active prior to listing their properties to ensure they have the proper paperwork.” In Queens and Brooklyn the Department of Buildings’ records are public online, in BIS and the DOB NOW Public Portal.
2. Close out permits for finished work. Ask the department what a final inspection and the certificate require, and who has to request them.
3. Legalize work that was never permitted. Departments have a process for existing work. The Town of Babylon, for one, publishes “Instructions to Maintain (legalize) a Structure.”
4. Ask about older structures. Where a structure predates the department’s certificates, ask what it issues instead. The names differ by town; the table below notes the ones each town’s site uses.
5. Restore what cannot be approved. If the zoning does not allow something, such as a second unit in a one-family house, ask the department what returning to the approved use involves.
6. Disclose it and settle it in the contract. A buyer and seller can agree how an open item is handled, and the attorneys put that agreement in the contract.

Questions to ask when the facts are in front of you

Once the file is in hand, these are the questions that tend to decide what happens next. They are questions for your attorney and the building department, not answers.

1. What does the file list, item by item: permits, certificates, open permits and any violations?
2. Does each certificate describe the house as it stands today: rooms, decks, pool, sheds, dormers, garage and basement?
3. For each open permit: was the work finished, who took out the permit, and what does closing it require?
4. Is there a violation on file, or only a missing certificate?
5. Does any structure predate the department’s certificates, and what does this department issue for that?
6. How long does the department say closing out or legalizing takes, and does that fit the closing date?
7. What does the contract say about certificates and open permits, and what happens if one is not cleared by closing?
8. Does the answer to Question 9 on the disclosure statement match the file?
9. If there is a second kitchen or apartment: does the zoning allow it, and is there a permit or licence for it?

Basement apartments and second kitchens

Whether a second unit is legal is a zoning and permit question, and the building department answers it, not the house. A basement apartment or second kitchen with no permit or approval on file is the kind of item the buyer’s attorney and lender ask about.

In New York City, the Department of Buildings defines an illegal conversion as “an alteration or modification of an existing building to create additional apartment units without first obtaining the proper permits or approval from DOB.” On Long Island the rules are each town’s or village’s own. The Town of Brookhaven, for example, says “An Accessory Apartment License is required to legally operate an accessory apartment within the Town.”

If the unit can be approved, the department explains how. If it cannot, ask what restoring the approved use involves. Either way, the attorney handling your sale advises on how it is handled in the contract.

Every building department in Nassau, Suffolk, Queens and Brooklyn

Your building department is the one for the municipality the house is in, which is not always the place named in its mailing address. Inside an incorporated village, the village keeps the building records; outside one, the town does (or, in Nassau, the City of Glen Cove or the City of Long Beach). If you pay a village tax bill, you are in a village. Queens and Brooklyn are both the NYC Department of Buildings.

Nassau County

Suffolk County

Suffolk has no cities. The Census also lists two reservations, Shinnecock and Poospatuck; they are not towns or villages, so they are not in this table.

Queens and Brooklyn

Every link above was opened on October 23, 2026. The list of towns, cities and villages is the U.S. Census Bureau’s (TIGERweb, current boundaries). If a link has moved, the municipality’s own website lists its building department.