# What is a parcel number (APN)?

> A parcel number (APN, PIN or parcel ID) is the unique ID a county assigns to each piece of land for taxes and records. What it looks like, where to find it, and why it changes.

Source: https://www.parceled.ai/guides/what-is-a-parcel-number-apn  
Publisher: Parceled (https://www.parceled.ai)  
Updated: 2026-10-06

A parcel number, usually called an assessor's parcel number (APN), is the unique identifier a county assessor assigns to each parcel of land for property tax and record-keeping. It also goes by parcel ID, PIN (property identification number), tax ID or folio number. You can find it on the property tax bill, the deed, or by searching the address on the county assessor's or GIS website.

- **Assigned by:** County (or township) assessor
- **Also called:** Parcel ID, PIN, tax ID, folio
- **Unique within:** One county, not nationwide

## What does an APN look like?

There is no national format. Each county designs its own, usually encoding the map book, page, block and lot, or the township, range and section. The same digits can exist in two counties, so a parcel is only uniquely identified by its APN plus its county (state and county FIPS code).

| Name | Where you see it |
| --- | --- |
| APN (assessor's parcel number) | California, Arizona, Nevada and many western counties |
| PIN (parcel/property identification number) | Illinois, Minnesota, North Carolina and others |
| Folio number | Miami-Dade and other Florida counties |
| Section-Block-Lot (SBL) | New York |
| Map-Block-Lot (MBL) | New England towns |
| Schedule number, account number | Some Colorado and Texas assessors use these alongside or instead of a parcel number |

## How do I find the parcel number for an address?

1. Look at the property tax bill or assessment notice; the parcel number is printed near the top.
2. Check the deed or closing documents.
3. Search the address on the county assessor's website or the county GIS parcel viewer.
4. Programmatically: Parceled's `search_parcels` returns the county parcel number (`parcelId`) for any latitude/longitude.

## Can a parcel number change?

Yes. When land is split, combined or re-platted, the county retires the old numbers and issues new ones, and some counties renumber whole areas when they redraw tax maps. Systems that track properties over time should store a stable internal ID and the county APN separately. Parceled returns both: its own stable `hailProId` and the county `parcelId`.

## Frequently asked questions

### Is a parcel number the same as a lot number?

No. A lot number comes from a recorded subdivision plat and identifies a lot within that subdivision. The parcel number is the assessor's tax ID. One parcel can contain several platted lots.

### Is the parcel number public information?

Yes. Parcel numbers are part of the public assessment roll.