Zillow (Bridge API) vs SimplyRETS 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. SimplyRETS is a developer API and WordPress plugin that turns your own MLS's RETS or RESO Web API feed into a simple REST 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.
- SimplyRETS: An affordable, simple REST layer for an agent or brokerage that already has its own MLS data feed.
Side by side
| Zillow (Bridge API) | SimplyRETS | |
|---|---|---|
| Searches | MLS listing data from the MLS partners connected to Bridge; a separate Public Records API covers parcel, assessment and county transaction data. | Listings from the MLS feeds you connect: active, under contract, pending and closed; residential, condo, rental, multifamily, commercial and land, plus open houses. |
| Returns | JSON listing records normalized to the RESO Data Dictionary (MLS Listings API). | Listing records with property details, photos, and listing agent and office information when the MLS feed supplies it. |
| Before the first call | An invitation: you request access through a form, and every MLS partner decides whether you get its data. | RETS or RESO Web API credentials from your MLS; whether you must be an agent or broker depends on the MLS. |
| Free | – | Free demo API keys with sample data; no free trial with live data. |
| Paid | – | Basic plan $49 a month, plus a one-time $99 fee per MLS connection. |
| Acting on a result | – | Listing agent and office contact details come with each listing when the MLS feed has them, and some MLSs require showing them. |
| Limits on keeping or showing results | – | Only listings flagged for IDX display are served, and you must follow the display rules (e.g. last-updated disclaimers) set by your MLS. |
| Coverage | US and Canada, but only for MLSs that partner with Bridge and approve you. | Whatever MLS you connect (US); no fixed national coverage. |
| MCP server | – | No official server listed |
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.
Questions people ask
What do I need before I can use SimplyRETS?
RETS or RESO Web API credentials from your MLS; whether you must be an agent or broker depends on the MLS.
Is SimplyRETS free?
Free demo API keys with sample data; no free trial with live data.
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.”
SimplyRETS, read on October 15, 2026:
- simplyrets.com: “These are our demo API keys, you can use them!”
- simplyrets.com: “Each RETS or RESO Web API connection requires one time $99 connection fee.”
- simplyrets.com: “Get RETS or RESO Web API credentials from your MLS”
- simplyrets.com/faq: “This is dependent on the MLS area you want to connect to.”
- docs.simplyrets.com/topics/fields-and-features-for-idx-compliance: “In some cases it may be required that you show the contact information for the listing agent and/or listing office.”
- docs.simplyrets.com/topics/fields-and-features-for-idx-compliance: “in many areas it’s required to show the timestamp of when the data was last updated in a disclaimer.”
- simplyrets.com: “Basic $ 49 /mo”
- simplyrets.com/faq: “We don't currently offer a free trial period with live data”