Code: BIN (Unique DOB building ID number)
Description: (Building Identification Number) is a unique 7-digit number that the NYC Department of Buildings uses to identify each building structure in the city and track all DOB records for that building.
Practical Meaning: For a homeowner, the BIN is a permanent 7-digit number that uniquely identifies a specific NYC building in DOB and other city systems, even if its street address or tax lot (BBL) later changes. Because each building keeps its original BIN for life except when correcting an assignment error, you should rely on the BIN when checking permits, violations, and complaints so you do not confuse your building with another that has a similar address, including cases where a demolished building and a new building share the same postal address but have different BINs.
Where You May See It: You may see the BIN on DOB NOW and BIS search results, on DOB permits and violation notices, in NYC planning or mapping tools, and in city benchmarking or energy-reporting forms that ask for a unique building identifier.
Why It Matters: The BIN matters because DOB and other city systems use it to pull the full record for a specific building, including open violations, complaints, permits, and enforcement actions that can affect safety, financing, and resale. If you use the wrong BIN, you may miss serious issues or think a violation is on your building when it actually belongs to a different one.