Zillow (Bridge API) vs HUD open data for AI agents
Zillow Group's developer portal lists APIs such as MLS Listings (served through the Bridge Listing Output platform), Public Records and Zestimates, and the listings and public records APIs are invite-only. HUD open data is a set of government datasets about HUD-subsidized multifamily properties (an ArcGIS feature service) and Fair Market Rents (HUD USER API); not a listings API.
The short answer
- Zillow (Bridge API): Brokers and approved vendors that already have MLS relationships and want a RESO-normalized feed from Zillow's Bridge platform.
- HUD open data: Mapping subsidized apartment buildings and checking rents against HUD Fair Market Rents, not finding a vacant unit.
Side by side
| Zillow (Bridge API) | HUD open data | |
|---|---|---|
| Searches | MLS listing data from the MLS partners connected to Bridge; a separate Public Records API covers parcel, assessment and county transaction data. | Locations and program details of HUD-subsidized multifamily properties; Fair Market Rent figures by area. |
| Returns | JSON listing records normalized to the RESO Data Dictionary (MLS Listings API). | Property locations and assistance-program attributes; FMR rent figures. No vacancy, availability or asking-rent fields are described. |
| Before the first call | An invitation: you request access through a form, and every MLS partner decides whether you get its data. | Nothing stated for the ArcGIS endpoint; the Fair Market Rents API needs a HUD USER account and an access token. |
| Acting on a result | – | Nothing: no property manager contact is described. |
| Coverage | US and Canada, but only for MLSs that partner with Bridge and approve you. | US |
Where Openpath fits
Openpath has no homes listed yet. Owners and landlords can list a home for rent or sale on Openpath today, free, and agents will find it through the same search as jobs and businesses. Get listed.
Sources
Every line about another company comes from its own pages. Prices and terms change, so check the source before you rely on one.
Zillow (Bridge API), read on October 15, 2026:
- zillowgroup.com/developers/api/mls-broker-data/mls-listings: “The Bridge Listing Output platform allows brokers and developers to access MLS listing data via a modern RESTful API.”
- zillowgroup.com/developers/api/mls-broker-data/mls-listings: “The platform is currently invite only, so please contact us for the latest list of available MLS integrations.”
- zillowgroup.com/developers/api/mls-broker-data/mls-listings: “All data access is at the discretion of our individual MLS partners in the US and Canada.”
- zillowgroup.com/developers/api/public-data/public-records-api: “This resource is really for commercial use cases by businesses.”
HUD open data, read on October 15, 2026:
- catalog.data.gov/dataset/multifamily-properties-assisted: “This dataset denotes HUD subsidized Multifamily Housing properties excluding insured hospitals with active loans.”