What Is a CD Number? How to Read a NYC Condo Offering Plan ID

Updated Sep 25, 2026 · 3 min read

Short answer: A CD number is the plan ID the New York State Attorney General gives a condominium offering plan: two letters and six digits, like CD250420, where 25 is the year the plan came in and 0420 its place in that year's line of filings. It stays with the filing and every amendment, and because serials run in order of submission (98% of neighboring IDs are in date order), it dates the sponsor's first submission even after amendments overwrite the AG's "Submitted Date." The ID year is not the acceptance year: only 44% of accepted plans were accepted in the year their ID carries.

How to Read a CD Number

Take CD250420, the Morgan Condominium at 38 East 35th Street in Manhattan:

Part	Value	What it tells you
CD	Prefix	A condominium plan
25	Two-digit year	The year the plan came in: 2025
0420	Serial	Its place in that year's line of filings

The serial runs in order of submission. Among the plans whose first submission date we recorded, 98% of 1,284 neighboring IDs are in date order. So the serial dates the plan even after amendments have erased the original date from the AG's record: the IDs on either side of it, CD250419 and CD250421, came in both on Dec 17, 2025, so the Morgan was first submitted around then. It was accepted for filing on Jul 1, 2026.

The ID year is not the acceptance year. Of the 7,423 accepted plans on The Condo Book Project, 44% were accepted in the year their ID carries, 50% the next year and 5% two or more years later. A late-year serial accepted the next spring is normal; a 2023 ID accepted in 2026 had a long review. (How long AG review takes.)

Older plans work the same way: CD06 is 2006 and CD98 is 1998.

CD vs. CC and Other Prefixes

Of the 8,338 plan records on The Condo Book Project, 8,128 start with CD and 19 with CC, which the Attorney General mostly uses for combined cooperative/condominium offerings. The prefix is a filing category, so check the plan type on the record rather than going by the letters.

Where to Find a Building's CD Number

In the Attorney General's database. Search the address or name in the Real Estate Finance database; the plan ID is at the top of the record. See how to search the AG's offering plans.
On The Condo Book Project. Every building page shows it, and the buildings directory lists every condo plan by borough.
In the new filings list. The newest NYC condo filings list every plan from the last month with its CD number, sellout, manager and attorney.

What You Can Do With a CD Number

Pull up the filing directly. Type it into the AG's database or The Condo Book Project's search and you land on one building, with no guessing about spellings.
Find every amendment. Amendments are filed under the same ID. See how to find and read offering plan amendments.
Spot a re-filed building. A building whose first plan was withdrawn or abandoned and later re-filed has two IDs. The older one tells you the project stalled once.
Cite it. In emails to a lawyer, lender or broker, the plan ID removes any doubt about which filing you mean.

FAQ

Is a CD number the same as a BIN or BBL?

No. A BIN (building identification number) and BBL (borough, block and lot) are New York City identifiers for a building and a tax lot. A CD number identifies an offering plan filed with the State Attorney General. One building can have more than one plan over the years.

Does a CD number change when the plan is amended?

No. Amendments are numbered (Amendment 1, 2, 3…) under the same plan ID.

How do I tell when a plan was first submitted?

Use the ID. The year and serial show when it came in, while the "Submitted Date" on an amended plan's AG record is the latest amendment's date.

Can I search The Condo Book Project by CD number?

Yes. Paste the plan ID into the search box, for example CD250420.