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MLS API access

MLS data comes from the MLS: each one decides who may read its listings, under its own licence, and most platforms that carry the feed still need that approval. This page explains the routes and what they cost, from each provider's own pages. Listingrail is not one of them; it reads public portals instead, and the last section says when that fits.

How MLS data access works

The standard. The RESO Web API is how MLS data moves today: a REST interface on OData V4 that replaced RETS, which RESO no longer supports. The RESO Data Dictionary names the fields, more than 1,700 of them, so feeds from different MLSs look alike. RESO writes the standard and holds no data.

The licence. According to RESO, you ask the MLS, agree to its data-use and licensing policies, and receive credentials from its software provider or staff. NAR requires MLSs owned by REALTOR associations to offer production access over the Web API.

The use. Licences are written per use. IDX lets MLS members show listings on their own sites; a VOW shows more, including sold data, to consumers who log in. Back-office and analytics uses have licences of their own where the MLS offers them.

Routes to MLS data

MLS data routes, checked 19 October 2026
RouteWhat it isWho gets accessCost
Your MLS, over the RESO Web APIThe MLS's own feed in the RESO standard (OData; RETS is retired)Whoever the MLS licenses, after agreeing to its data-use policiesSet by each MLS
Zillow Group MLS Listings (Bridge)MLS listings normalised to the RESO Data Dictionary, by REST APIInvite only; each MLS partner decidesNot published
Spark API (FBS)MLS data plans (IDX, VOW and others) bought in the Spark DatamartKeys issued only with the MLS's approvalPer MLS data plan; free demo credentials with example data
MLS GridOne feed and one licence for IDX, VOW and back-office useBrokers only from MLSs where they hold participatory rightsThe MLS's licence fee, collected by MLS Grid
Trestle (Cotality)MLS data platform; MLSs approve each connection by use casePer connection, approved by the MLSFree to MLSs; not stated for data users
SimplyRETSA REST API on top of credentials you already hold from your MLSAnyone with MLS credentialsFrom $49 a month per feed plus $99 once; free demo data
REALTOR.ca DDF (Canada)CREA's service for sharing listings with third-party sites and members' own sitesREALTORS and broker owners, who control how their listings are sharedNot stated

MLS feed or portal listings

What each gives you
MLS feedListingrail
SourceThe MLS: what member agents enterPublic portals: what Zillow, Rightmove or Idealista show a visitor
Who can get itMLS members and vendors the MLS licensesAnyone with an email address
Time to first dataApproval by each MLS, then a licenceA key at once, 100 listings free
CoverageOne MLS per licence, US and Canada17 portals in 11 countries; no MLS
FieldsRESO Data Dictionary, 1,700+ fields; sold data with VOWThe same 23 fields on every portal, as far as the portal shows them, plus its own record
Display rulesIDX and VOW rules of the MLSThe portal's terms and your local law

Use the MLS feed for a brokerage's IDX website, for sold data, and wherever the MLS licence is a requirement of your customer.

Use portal listings when you have no MLS membership, need rentals from the big rental portals, need countries outside the US and Canada, or want new listings and price cuts across several portals for research, lead lists or alerts. Zillow, Redfin, Zumper, Apartments.com and Craigslist cover the US side; the portal list has the rest.

US listings without an MLS licence

Homes for sale in Austin with three or more bedrooms, as Zillow shows them. POST it to /v1/listings/search with your key; the Zillow Python guide runs it end to end.

{
  "source": "zillow",
  "location": "Austin, TX",
  "minBeds": 3,
  "limit": 50
}

Pricing

TicketListings a monthPer listingPrice
Free100, oncefree$0
Starter10,000$0.0029$29 /mo
Pro50,000$0.0020$99 /mo
Scale250,000$0.0012$299 /mo

One credit is one listing returned. A search that finds nothing, or fails at the portal, is not charged. Choose a plan.

Questions about MLS APIs

What is an MLS API?

An interface to a multiple listing service's data, normally over the RESO Web API, the industry standard that replaced RETS. RESO writes the standard but holds no data: the MLS licenses its own listings.

How do I get MLS API access?

Ask the MLS. According to RESO, data requests go to the MLS, you agree to its data-use and licensing policies, and credentials then come from the MLS's software provider or staff. Platforms such as Spark, MLS Grid, Trestle and Zillow's Bridge carry the feed, but each MLS still approves who gets it.

Is there a free MLS API?

Not for live data. Spark gives free demo credentials with example data, and SimplyRETS has free demo data; real listings come under the MLS's licence. Trestle is free to MLSs, not to data users.

How much does MLS API access cost?

The MLS sets its licence fee, and a platform may add its own: SimplyRETS starts at $49 a month per feed plus a one-time $99 connection fee; MLS Grid collects the MLS's fee; Spark sells MLS data plans whose prices each MLS sets.

Can I get MLS data without being an agent?

It depends on the MLS. Spark issues keys only with an MLS's approval, MLS Grid gives brokers data only from MLSs where they hold participatory rights, and SimplyRETS says whether an agent or broker is needed depends on the MLS area.

What are IDX and VOW?

In Spark's documentation, IDX is an MLS policy that lets authorized MLS members show designated MLS listings on their websites and apps, and a VOW is a site where the consumer logs in and may see more, including sold data.

Is there an MLS API for Canada?

CREA's REALTOR.ca DDF shares listings with third-party sites and members' own sites; REALTORS and broker owners control how their listings are shared.

Is Listingrail an MLS API?

No. Listingrail reads public property portals and returns their listings. It has no MLS feed, no sold data and no IDX licence. It suits analysis, alerts and tools that work across portals and countries; an IDX website for a brokerage needs the MLS feed.

Sources

NAR's own IDX policy page required a login when we checked; the IDX and VOW definitions above are Spark's.

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