Find a Nassau County section, block and lot
From the New York State assessment roll for Nassau County.
How Nassau’s tax map numbers work
A Nassau property’s tax map number is its section, block and lot, written like 12-345-67. The section is a sheet of the county land and tax map, the block a block on that sheet (sometimes with letters, like 32-J), and the lot the parcel itself.
The same county map covers the towns of Hempstead, North Hempstead and Oyster Bay and the cities of Glen Cove and Long Beach, and the number appears on your assessment notice, your school and general tax bills, and grievance forms.
Where to see the official tax maps
The county’s Land Records Viewer shows the tax map, with each parcel’s section, block and lot and its assessment details. Deeds and mortgages recorded in Nassau carry the property’s section, block and lot, which the county verifies against the tax map.
For what a property pays and which school district it’s in, look it up with the property tax calculator; for school district boundaries and median bills, see the Long Island tax map.
Frequently asked questions
How do I find my Nassau County section, block and lot?
Type your address into the lookup above. It’s also on your tax bill and assessment notice, and in the county’s Land Records Viewer.
Is the tax map number the same as the SBL?
Yes. In Nassau, “tax map number”, “section, block and lot” and “SBL” all mean the same identifier. See section, block and lot.
Why do I need my section, block and lot?
It’s how the county finds your property: you’ll use it to look up or pay a tax bill, to file an assessment grievance, and on deeds and mortgages.
Sources and citations
- Nassau County Land Records Viewer (LRV) lrv.nassaucountyny.gov
- NY State Open Data — Property Assessment Data data.ny.gov
Last verified October 16, 2026. Tax rules change; we re-check every page each quarter.
Educational content and estimates only, not legal, tax or financial advice. Verify with your county or town receiver, an attorney or a CPA before making financial decisions.