Top 20 MLS Real Estate Listings in the United States

What are the largest MLS real estate listings in the United States? The table gives you the most updated list (10/31/2021), as well as links to their homepages, and their 2021 Membership numbers.

The National Association of REALTORS (NAR) is North America’s largest trade association for real estate helped set the general requirements for IDX and does a good job of coordinating the industry but the MLS space is a continually shifting landscape.

In December of 2020, a RESO official cited about 556 MLS’s. Over the course of the last year, the median subscriber count per MLS grew about 18.8 percent.

Feel free to bookmark this page for your resource of the top MLS’s in the country. We’ll continue to update it for you, so you have a single resource.

Rank Company Name Corporate Office 2021 Membership
1 California Regional MLS San Dimas, CA 104,414
2 Bright MLS Rockville, MD 94,429
3 Stellar MLS Maitland, FL 64,552
4 First Multiple Listing Service Atlanta, GA 48,991
5 MIAMI Association of Realtors (SEF Shared MLS Database) Miami, FL 47,694
6 Midwest Real Estate Data Lisle, Il 47,251
7 Georgia MLS Tucker, GA 44,995
8 MLS Property Information Network Shrewsbury, MA 43,813
9 North Texas Real Estate Information Systems Dallas, TX 43,000
10 One Key MLS (formerly New York MLS or NYMLS) West Babylon, NY 42,450
11 Arizona Regional MLS Tempe, AZ 40,926
12 Houston Association Of Realtors Houston, TX 40,002
13 Beaches MLS West Palm Beach, FL 36,000
14 Northwest MLS Kirkland, WA 32,656
15 Garden State MLS Parsippany, NJ 25,912
16 Metrolist Sacramento, CA 25,039
17 REcolorado Greenwood Village, CO 24,241
18 Northstar MLS St. Paul, MN 20,818
19 CanopyMLS (formerly Carolina Multiple Listing Service or CMLS)  Charlotte, NC 20,197
20 SMART MLS Wallingford, CT 19,220

What is an MLS?

A multiple listing service (MLS, also multiple listing system or multiple listings service) is a suite of services that real estate brokers use to establish contractual offers of compensation (among brokers) and accumulate and disseminate information to enable appraisals. A multiple listing service’s database and software is used by real estate brokers in real estate (or aircraft broker[1] in other industries for example), representing sellers under a listing contract to widely share information about properties with other brokers who may represent potential buyers or wish to work with a seller’s broker in finding a buyer for the property or asset. The listing data stored in a multiple listing service’s database is the proprietary information of the broker who has obtained a listing agreement with a property’s seller.

In the late 1800s, real estate brokers regularly gathered at the offices of their local associations to share information about properties they were trying to sell. They agreed to compensate other brokers who helped sell those properties, and the first MLS was born, based on a fundamental principle that’s unique to organized real estate: Help me sell my inventory and I’ll help you sell yours

National Association of Realtors

There is no single authoritative MLS and no universal data format. However, there is a data standard for MLS systems—the Real Estate Transaction Standard—which is being deployed across MLS solutions in North America. However, the Real Estate Standards Organization has been spearheading the industry’s move to use more modern data formats, standard data definitions/fields, and coordinate leading industry organizations to build a new future of real estate data.

Getting Your MLS on Your Real Estate Website

Each MLS in the U.S. are independent and offers direct data feeds to technology vendors via RETS and/or Web API. Our proprietary MLS aggregation technology connects your local MLS into our IDX engine and the most advanced home search available.

We deal with technology, so you do not have to, and we love geeking out on innovative technology that people use every day. How much do we love data and software people love? The Real Estate Standards Organization (RESO) wrote a case study on us, how our team helped build the navigation apps in your car and on your phone (pages 6 – 7, and Showcase IDX’s role in the real estate industry over the past 20+ years).

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Entrepreneurial marketing leader that’s built and run organizations from start-up to over $500M annual revenue. He brings a unique combination of storytelling and innovation to the team, having led marketing for many brands. Kurt’s a regular conference speaker and workshop leader around modern marketing tactics that actually drive sales. In addition, he has been asked to coach and advise thousands of leaders, from startup founders to the President of the United States.

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