If you're a contractor, real-estate investor, or developer, building permit
data is one of the most useful public datasets in the US, it tells you who's
building, renovating, or installing solar, roofing, and HVAC, by address and date.
Here's how to get it yourself, for free, from official government data.
Most US cities publish permits as open data
Cities like Austin, Chicago, New York, LA, and Seattle run open-data portals on
a platform called Socrata. Each portal exposes a public API, no scraping, no key
needed for basic use. For example, Austin's issued construction permits live at
data.austintexas.gov, dataset 3syk-w9eu.
Pulling permits with one query
Socrata uses a query language called SoQL. To get the most recent permits, you
hit the dataset's API endpoint and filter by date. For Austin:
https://data.austintexas.gov/resource/3syk-w9eu.json?$where=issued_date > '2026-01-01'&$order=issued_date DESC&$limit=50
That returns clean JSON: permit type, address, valuation, contractor, dates.
Swap the domain and dataset ID for other cities and you get the same data.
The catch
Every city names its columns differently, the date fields vary, and you have to
re-pull and de-duplicate constantly to get only new permits. Doing this across
even 5 cities by hand gets old fast.
The shortcut
I got tired of maintaining this for multiple cities, so I built a tool that
normalizes every city into one schema, runs daily, and returns only new permits, pay only for the rows you get. If you'd rather skip the plumbing, it's here:
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