NYC BBL Lookup: How to Find Your Borough-Block-Lot from an Address

Every property record in New York City — violations, deeds, mortgages, tax assessments, permits, even FEMA flood determinations — is keyed to a 10-digit identifier called a BBL: Borough-Block-Lot. If you've ever tried to look something up on ZoLa, ACRIS, BIS, or NYC Open Data and hit a "Property not found" error after typing the address, the answer is almost always: you needed the BBL, not the street address. Here's how to derive one in under a minute.

What a BBL actually is

BBL stands for Borough-Block-Lot. It's a 10-digit numeric key the city uses internally for every taxable parcel:

• 1 digit for borough — 1=Manhattan, 2=Bronx, 3=Brooklyn, 4=Queens, 5=Staten Island.
• 5 digits for the tax block (zero-padded).
• 4 digits for the tax lot (zero-padded).

Example: 1008350041 → Manhattan (1), block 00835, lot 0041 → the Empire State Building. Once you have the BBL, every NYC dataset opens up: PLUTO returns lot characteristics, ACRIS returns deeds and mortgages, the HPD/DOB/OATH datasets return violations, and FEMA's flood layer aligns to it via the lot polygon.

Three ways to get the BBL from an address

1. NYC Geosearch (fastest, official)

The Department of City Planning runs a free address-resolver at geosearch.planninglabs.nyc. It returns the canonical BBL for any street address plus a confidence score. This is what most modern apps use under the hood — the same service powers ZoLa's address bar.

2. ZoLa (the city zoning map)

Open zola.planning.nyc.gov, type the address into the search box, and click the parcel. The BBL appears in the right-hand sidebar under "Tax Lot Information." Useful if you want to see the lot on the map and verify which parcel you're looking at — important for corner buildings or buildings that span two lots.

3. ACRIS (if you only have a recent deed)

ACRIS — the city's deed and mortgage database — lets you search by party name or document number. Every recorded document includes the BBL. If you have any past deed, mortgage, or UCC filing on the property, the BBL is in the document index.

Five gotchas that break BBL lookups

• Corner buildings often have two valid street addresses (e.g. "123 Main St" and "456 Side St"). The BBL is the same — but only one address may resolve cleanly in geosearch.
• Condo units get their own BBL. The "building BBL" (the underlying lot) is different from the "unit BBL" you see on a condo deed. PLUTO indexes the building BBL; ACRIS indexes both.
• Recently subdivided lots may not propagate to PLUTO for a year or more. If a building was carved up after the most recent PLUTO release, you'll get the old combined BBL.
• Vacant lots after demolition keep their BBL but may show no building data — violations from the prior structure can still be open.
• Government parcels (parks, schools, courthouses) have BBLs but aren't taxed; they may return empty in some datasets. Our reports gate on these by design.

When you actually need the BBL

For most renters and buyers, you don't need to memorize the BBL — you just need a tool that resolves it for you. NYC Property Audit takes a street address and runs the resolution chain (geosearch → PLUTO → BBL → all-agency lookup) in one shot: try a free address search →