Blocks & Lots

What is a Building Identification Number?

A Building Identification Number (BIN) is a unique identifier for each NYC building.

The Department of City Planning assigns Building Identification Numbers, though the Department of Buildings may do so as well. The DOB uses BINs to track permits, codes, and violations.

Therefore, BINs are helpful for condo owners and buyers. They can help you identify a building in government databases.

One use for this is figuring out if there are violations on your property. This is important because building violations can lead to fines and penalties. Violations can also prevent you from refinancing or selling your home.

You’ll notice the BIN in the certificate of occupancy below. A CO is one of the ten key documents in the life of an NYC building.

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You may be wondering how a BIN differs from a BBL, the identifier of your home’s borough, block, and lot. The Department of Finance issues the BBL, which it uses for tax purposes. By contrast, as we covered above, the DOB uses BINs.

BINs are more specific than BBLs. This is especially pertinent when it comes to co-ops because a single co-op may include several buildings and many units. All these units will share one BBL, or one block and lot. However, the buildings in the co-op will have different BINs.

Therefore, knowing a BIN can help you identify your co-op building in public records when knowing a BBL will not. But this is not the case for condos, for which each unit has a different lot number.

How to find Building Identification Numbers

The best place to find your Building Identification Number is on real estate data and analytics platform Marketproof. Marketproof classifies buildings at the individual BIN level, whereas many other property sites only go to the block-and-lot level.

Consider this Stuy Town building. The blue region covers the block and lot that contains this building. But the single building shaded purple is the actual building. Marketproof isolates this data so that you get a clearer view of properties you own or would like to consider buying.

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Top photo courtesy of 215 Chrystie St.