What are property lines?
A property line is the recorded edge of a parcel. It separates one owner's land from the next and is defined by a legal description that lives in the recorded deed, the subdivision plat, and the county parcel record. On a map, the same edge usually appears as a polygon drawn from county GIS data.
Property lines on a map are usually approximate. The legal boundary is the one a licensed surveyor places on the ground, using the deed and recorded plats. Parcel maps are great for research and orientation, and they are not a substitute for that legal boundary.
Where parcel data comes from
Counties manage parcel records. The assessor's office tracks parcels for tax purposes and assigns each one an Assessor's Parcel Number, often called an APN. The recorder's office holds deeds, plats, and other documents that define the boundary. Many counties also publish a public GIS viewer that draws parcels on a map.
Because every county runs its own systems, parcel data quality varies. Large metro counties usually update frequently and publish clean polygons. Smaller rural counties may update less often and may not publish parcel data online at all. A nationwide app like Landy's parcel map normalizes those sources into a single view.
Five steps to find a property line
- 1. Start with the address. Search the address in Landy's property line finder or the relevant county GIS site. The parcel polygon and APN should load on the map.
- 2. Read the parcel card. Confirm acreage, lot dimensions, and the parcel ID. If something looks off, double check with the county's official record. The APN lookup guide explains parcel number formats in more detail.
- 3. Check the deed and plat. The recorded deed and any subdivision plat are the authoritative descriptions of the boundary. Counties typically expose these through the recorder's office.
- 4. Walk the lines with GPS. Stand on the property and use a phone with GPS to see how the parcel polygon lines up with the ground. Look for survey monuments, iron pins, or fence corners that confirm the boundary.
- 5. Hire a surveyor for legal decisions. Fence placement, easement disputes, construction setbacks, and land sales need a licensed survey. Use parcel maps to research, and use a surveyor to confirm.
Tools you can use
Landy is built around a handful of focused tools you can mix and match for property research.
- Property line finder for approximate lot lines and GPS overlay.
- Parcel map for browsing parcels and lot cards.
- APN lookup for finding and cross referencing parcel numbers.
- Property boundaries for reading boundary lines in context.
- Land measurement for estimating distance and acreage.
- Coverage by state to browse state and county hubs.
Common mistakes to avoid
Three mistakes show up over and over in property line research.
- Treating a map polygon as the legal boundary. Maps are approximate. Surveys are legal.
- Ignoring easements. They usually live in deed records, not parcel maps, and can change what you can do on a lot.
- Skipping the on-site walk. A GPS walk against the parcel polygon catches mismatches between published data and what is actually on the ground.