A BBL — Borough, Block and Lot — is the unique fingerprint of every piece of land in New York City. If an address is how people find a building, the BBL is how the city finds it: in tax records, deeds, mortgages, permits and violations.
A BBL has three parts that combine into a 10-digit number. The borough is a single digit: 1 = Manhattan, 2 = the Bronx, 3 = Brooklyn, 4 = Queens, 5 = Staten Island. The block is up to five digits identifying a city block within that borough. The lot is up to four digits identifying the individual parcel on that block.
Written out, the parts are padded with zeros: borough (1 digit) + block (5 digits) + lot (4 digits). For example, the Empire State Building is BBL 1-00835-0041, usually stored as the 10-digit string 1008350041.
Lot numbers from 1 up are the physical tax lots you can see on a map. Lot numbers of 1001 and above are typically condominium unit lots — individual apartments carved out of a single base lot. That is why a 50-unit condo building can have one street address but dozens of BBLs.
This matters for research: a condo unit's BBL exists in deed and tax records but often has no standalone polygon on the property map, because the physical footprint belongs to the base lot. Tools that map by BBL frequently fall back to the address for condo units.
Once you have a BBL you can pull almost everything the city knows about a parcel: the deed history and last sale (ACRIS), the lot size, zoning and building area (PLUTO), recorded mortgages, tax liens, building permits and open violations. On Crezly, the BBL is the key that ties a property to its owner, its debt and its transaction history.
You can search any NYC parcel by BBL, owner name or street address on the Crezly property map, and see recorded deeds, liens and mortgages in the Data Suite.
What does BBL stand for?
BBL stands for Borough, Block and Lot — the three components of the number that uniquely identifies every tax parcel in New York City.
How many digits is a BBL?
A standard BBL is 10 digits: 1 for the borough, 5 for the block and 4 for the lot, zero-padded (for example 1008350041).
What do the borough numbers mean?
1 is Manhattan, 2 is the Bronx, 3 is Brooklyn, 4 is Queens and 5 is Staten Island.
Why does one building have several BBLs?
Condominium buildings assign a separate unit lot (numbered 1001 and up) to each apartment, so a single building can carry many BBLs even though it has one address.