Code: BBL (official acronym)
Description: Borough, Block, Lot - a 10-digit identifier provided by the Department of Finance to identify a tax lot that contains one or more buildings in NYC.
Practical Meaning: In simple words, a BBL works like a property ID number. City agencies use it to connect records for taxes, ownership, permits, violations, and building data. A BBL is usually shown as three parts: borough, block, and lot. In many systems, it is stored as one 10-digit number. Homeowners often need the BBL when searching property records, checking tax information, or using official city lookup tools.
Source: BBL lookup