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Part of US homes by city: a visual planning guide for 2027
US homes by city prices: what to know and why
US homes by city records: which office holds deeds, assessments, permits and survey files, and a sequence for finding them in any jurisdiction.
The hardest part of researching an American building is not reading the records. It is finding out which office holds which record, because the answer changes at every county line. There is no national property register. There is a patchwork of county recorders, city building departments, assessors and state preservation offices, each with its own portal, its own vocabulary and its own idea of what belongs online.
This page is a method for finding the right office anywhere, and a warning about what each kind of file is for. It names no property, publishes no figures and identifies no person.
What to take away
- Four different offices typically hold the four record types, and only one of them is likely to be the one you first thought of.
- What is online varies enormously; a record that does not appear in a search usually exists on paper at a counter.
- The office that holds a record also defines its terms, so read the office's own glossary before reading the record.
Who holds what
| Record | Usually held by | What it was created to do |
|---|---|---|
| Deeds and conveyances | County recorder, register of deeds, or clerk | Give legal notice of an interest in land |
| Assessment and parcel data | County or city assessor | Classify and value property for taxation |
| Building permits and inspections | City or county building department | Authorize and inspect work |
| Historic designation and survey | City preservation office and the state historic preservation office | Identify and protect significant property |
The overlaps cause most of the confusion. Parcel maps may come from the assessor or from a separate mapping office. Permits may be split between building, planning and fire. Historic survey data may sit with a city, a state office, a university, or a nonprofit that did the fieldwork.
A sequence that works anywhere
- Start with the parcel identifier. Almost every system keys on it, and it is the one value that lets you move between offices without ambiguity.
- Find the assessor first, because assessor portals are the most consistently online and usually carry the parcel number, the parcel map and a basic building description.
- Take the parcel number to the recorder's index for instruments, and to the building department for permits.
- Ask the state historic preservation office about survey coverage. Many buildings that are not designated have nonetheless been surveyed, and the survey form is often the only researched description that exists.
- Read each office's own explanation of its fields before drawing anything from them.
For the national layer that sits above all of this, the National Register database and how to search it explains what the federal file contains and how it is organized. Where a city has published its parcel and planning data as open datasets, that is usually the fastest route in; one large city's approach is described at its planning open data page, and the same pattern now exists in most major jurisdictions.
What varies, and why it matters
Coverage varies by decade. Many portals begin at a scanning cutoff. Everything before that date exists on microfilm or paper, and a search that returns nothing for an old building is usually telling you about the portal rather than about the building.
Terms vary by office. Building area, story count, room count, condition class and use code are all defined locally, and two counties can record the same building differently while both being correct. This is the single most common source of bad comparisons between cities.
Access varies by policy. Some jurisdictions publish parcel-level data openly. Others restrict it, redact fields, or require a request. A restriction is a policy choice, not an obstacle to be worked around, and this site treats it as a limit to respect.
Why the underlying lot geometry differs so much between cities in the first place is set out in homes by city, and what any of these records can honestly support is in how property records work. For the dense-city version of the same research problem, see reading the record calendar, and for how these layers appear on a map, reading public map layers.
Common questions
Is there a single national property database?
No. Aggregator sites present themselves as one, but they are compilations of local records of varying age and accuracy, and they carry no authority. Go to the office that made the record.
Why can I find a building's permits but not its deeds, or the reverse?
Because the two are held by different offices with different digitization histories. A gap in one system says nothing about the other.
What if the record contradicts the building?
The building wins as evidence of what exists. The record wins as evidence of what an office decided, on the date shown. Both statements can be true at once.
Should I use a commercial property data service?
For orientation, sometimes. For anything you intend to state, go to the source record, because a compiled dataset inherits every error in its inputs and adds its own normalization on top.
