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If you work with New York City property data, you have probably run into a moment where an address alone is not enough. Two listings can point to the same building, a corner property can carry several legal addresses, and a single tower can hold hundreds of separate tax lots. The identifier that cuts through all of that is the city's parcel number.
This guide walks through what that number is, how it is built, and every free way to look it up. The goal is simple: by the end, you will be able to find the right records for any NYC property with confidence, whether you are checking taxes, pulling title documents, or building a list of leads.
What a Block and Lot Number Is
In New York City, every piece of real estate is assigned a parcel number. BBL is the official NYC abbreviation for Borough-Block-Lot, and that ten-digit number is how the Department of Finance and most city systems identify a property behind the scenes.
The address you see on the door is for people. The block and lot number is for the city's databases. It stays consistent across the tax rolls, ACRIS, permit records, and mapping tools, which is why a quick "nyc bbl lookup" is often more reliable than searching by street address. When an address comes up empty or returns the wrong unit, the parcel number gets you to the exact property every time.
You will need it for routine tasks like paying property taxes, filing Department of Finance applications, and pulling recorded documents. For investors, it is also the thread that ties one property's records together across every public source.
How a NYC Block and Lot Number Is Structured
The ten digits are not random. They break into three parts, read left to right: one digit for the borough, five digits for the block, and four digits for the lot.
The first digit tells you the borough. The next five identify the tax block, and the final four identify the specific lot within that block. When a block or lot number is shorter than its slot, it is padded with leading zeros so the total always lands at ten digits.
Here is how the borough codes map out.
| Borough | Borough Code (First Digit) |
|---|---|
| Manhattan | 1 |
| Bronx | 2 |
| Brooklyn | 3 |
| Queens | 4 |
| Staten Island | 5 |
A worked example makes the padding clear. Say a building sits in Brooklyn, on block 1129, lot 7501. Brooklyn is borough 3. The block 1129 is padded to 01129, and the lot 7501 already fills its four digits. Put them together and the parcel number is 3011297501.
Once you can read a number this way, you can also work backward. If a document lists the parcel as 1000237501, you know it is in Manhattan (1), on block 23 (00023), lot 7501. Reading the number in both directions saves time when you are scanning records quickly, and it helps you catch a typo before it sends you to the wrong property.
How to Do a Block Lot Lookup in NYC
There are several free, official ways to find a property's parcel number. Each one starts from the address and returns the borough, block, and lot. Pick whichever fits your workflow.
NYC Property Information Portal
The Department of Finance runs the NYC Property Information Portal, which is the most current and straightforward option. Enter the street address, select the matching property, and the borough, block, and lot appear at the top of the property's page along with its tax and ownership summary. This is usually the fastest starting point.
ACRIS
ACRIS, the city's Automated City Register Information System, is built for recorded documents like deeds and mortgages. To find a parcel number, choose "Find Addresses and Parcels," enter the borough and street address, and the system returns the block and lot. Since you are already in ACRIS, this method is convenient when your next step is pulling the deed or checking liens. If liens are part of your research, our complete guide to property lien searches walks through that process.
NYCityMap (NYC GIS)
If you think geographically, the city's mapping tool is a good fit. Open NYCityMap, type in an address, and the parcel details, including the block and lot, display in the information panel. The map view also helps when you are working a neighborhood block by block, which pairs naturally with driving for dollars.
Your Property Tax Bill
If you already own the property or have a copy of the bill, the simplest route is to read it directly. The borough, block, and lot are printed on every NYC property tax statement. No search required.
To make the choice easier, here is how the four free methods compare at a glance.
| Method | What You Need | Best For |
|---|---|---|
| Property Information Portal | Street address | A fast, all-in-one summary |
| ACRIS | Borough and address | Pulling deeds and documents next |
| NYCityMap (GIS) | Address or map location | Working an area block by block |
| Property Tax Bill | A copy of the bill | Properties you already own |
What You Can Find Once You Have the Parcel Number
Finding the number is only the first step. Its real value is that it unlocks the rest of a property's public record, and every source uses the same ten digits to file that information. Once you have it, a BBL lookup NYC opens up four kinds of records in particular.
- Tax status. The Department of Finance ties assessed value, exemptions, and any unpaid balances to the parcel number. This is also how you confirm whether a property owes back taxes.
- Ownership. The tax roll lists the owner of record, which is the name you will want before any outreach.
- Recorded documents. In ACRIS, the parcel number pulls the deed, mortgage, and lien history so you can see how a property has changed hands.
- Zoning and land use. The city's mapping tools link zoning, lot size, and building details to the same number, which matters if you plan to build or change use.
Because every system speaks the same language, the parcel number lets you move from one record to the next without losing your place. That consistency is what makes it the foundation for serious research.
Finding the Block and Lot for a Specific Condo Unit
Condos add one wrinkle. The building has its own block and lot, but each individual unit also carries its own lot number. In most cases, condo unit lots begin with 75, which is why you will often see lots like 7501 or 7502 on newer towers.
When you run a lookup for a condo, confirm whether the number you found points to the whole building or to a single unit. If you need a specific apartment, look for the unit-level lot rather than the building's base lot. Pulling the wrong one is a common reason records do not match up later, so it is worth a second glance before you move on.
Using Block and Lot Data as an Investor
For investors, a parcel number is more than a filing requirement. It is the key that connects ownership, tax status, and sales history across every public source. Once you have it, you can confirm the legal owner, check for delinquent taxes, and verify you are looking at the exact property you intend to contact.
That matters most when you are building a targeted list. New York investors often start from a category, such as tax delinquent properties in New York, then use parcel-level data to confirm each lead before reaching out. A clean NYC block and lot lookup on each address keeps the list accurate from the start.
The slow part is rarely finding one parcel number. It is doing the lookup for hundreds of properties and then locating the people behind them. That is where a tool helps. DealMachine's automated owner lookup pulls property and ownership data so you can go from a list of addresses to verified owner details without checking each record by hand, and accurate skip tracing fills in the phone numbers and mailing addresses you need to follow up.
Putting It to Work
A block lot lookup in NYC comes down to one habit: when an address is not enough, reach for the parcel number. Read the ten digits, confirm whether you are looking at a building or a unit, and use one of the free city tools to pull the record. From there, you have a clean foundation for taxes, title work, or a lead list.
If your next step is turning those parcels into conversations with owners, DealMachine can handle the lookup and outreach side for you. From here, you can decide what makes sense for your own workflow.
Frequently Asked Questions
What does BBL stand for in NYC real estate?
BBL is the official NYC abbreviation for Borough-Block-Lot. It is the ten-digit parcel number the Department of Finance uses to identify every individual piece of real estate in the city.
How many digits is a NYC block and lot number?
Ten digits in total: one for the borough, five for the block, and four for the lot. Shorter block or lot numbers are padded with leading zeros so the full number always reaches ten digits.
How do I find a block and lot number for free?
Use any of the city's free tools. The NYC Property Information Portal, ACRIS, and NYCityMap all return the borough, block, and lot from a street address, and the number is also printed on your property tax bill.