The difference is one word and it is the whole story: a Temporary Certificate of Occupancy expires. A final Certificate of Occupancy does not. A TCO says the Department of Buildings is satisfied a building is safe to occupy right now, while items remain outstanding; a final certificate says everything is finished, approved, paid for and cleared. Both let you live there legally. Only one of them stays true without anybody doing anything.
Side by side
| TCO | Final C of O | |
|---|---|---|
| Expires? | Yes — typically 90 days | No |
| Must be renewed? | Yes, in 30, 60 or 90-day increments | No |
| Outstanding items? | Some remain | None |
| Open violations? | Possible | Must be cleared |
| Other agency sign-offs? | May be pending | All received |
| Safe to occupy? | Yes — that is what it certifies | Yes |
DOB is explicit that a final certificate is issued only once the completed work complies with the applicable laws, all paperwork is complete, all fees owed to the department are paid, relevant violations are resolved, and the necessary approvals from other city agencies are in. A TCO is the acknowledgement that a building has cleared the safety bar but not yet that list.
Why new buildings open on a TCO
Almost every new residential building in New York opens under a temporary certificate. Construction finishes floor by floor, sign-offs from other agencies arrive on their own schedule, and a developer with completed apartments and waiting tenants has an obvious reason not to sit empty until the last piece of paper lands. The TCO exists precisely for that gap. Its presence on a new building is normal and is not, by itself, a sign of anything wrong.
When it stops being normal
The thing to look at is not whether a building has a TCO but how long it has had one. A renewal every 90 days for six months is a project finishing. The same cycle running for years usually means final sign-offs were never completed — sometimes a genuinely minor paperwork item, sometimes an unresolved violation or a dispute with another agency. And a TCO that has been allowed to lapse without renewal is a different matter again: the building's legal authority to be occupied has gone stale, which can affect financing, sales and insurance.
None of this is proof of a serious defect, and it should not be read as one. It is a question worth asking rather than an answer.
Which certificate your building has
Certificates are public, filed against the building's BIN. Newer ones live in DOB NOW, older and historical ones in the legacy Buildings Information System — see DOB NOW vs BIS, because a certificate can sit in either and looking in only one is the commonest reason people conclude a building has none.
And some buildings genuinely have none. New York did not begin issuing certificates of occupancy until 1938, so a building erected before then is generally not required to have one unless later work changed its use, egress or occupancy; the owner can instead obtain a Letter of No Objection confirming the legal use. Finding no certificate on a century-old walk-up is usually ordinary. The full picture is in what is a certificate of occupancy.
Why it matters to a tenant
The certificate states how many dwelling units a building legally has and what each floor may be used for. If your apartment is not accounted for in that legal use — an extra unit carved out of an approved layout, or a converted cellar — it may not be a legal dwelling unit, with real consequences for safety and for your rights. That is the question the certificate answers, and the reason it is worth checking before signing a lease. You can look it up free at Check a Building.
Sources: NYC DOB — Certificate of Occupancy and Temporary Certificate of Occupancy pages, and Code Notes: Certificate of Occupancy. General information about public records, not legal advice. Always confirm a building's current certificate status with DOB.