National association of realtors | MLS & Online Listings |

MLS & Online Listings


The multiple listing service, or MLS, is a facility that allows real estate professionals to learn about and share local property listings in support of the interests of clients and customers. REALTORS® enjoy an economical, efficient system of sharing real property information and facilitating cooperative transactions, while their clients and customers have access to the most accurate and up-to- date property information available. There are hundreds of MLSs across the country, which use a common set of rules to enable a smooth exchange of information in their local communities. MLSs provide a means for participants to offer compensation to other participants and enhance cooperation among them. As applications of Internet technology to the real estate business have increased in number, quality, and acceptance by the public, most real estate brokerage firms have established "online identities." MLSs have adopted Internet Data Exchange (IDX) programs as a means of enhancing cooperation between REALTORS®. Under IDX, brokers exchange consent to display each other’s listings on participants’ websites and using applications for mobile devices that participants control. Many MLSs, as a service to their members, also provide listing information to third-party aggregators such as realtor®.com and others through syndication or other similar type agreements, unless the broker withholds consent.

MLS & Online Listings Topics


Managing and protecting listing content is a paramount concern to real estate professionals and the multiple listing services in which they participate. In response to this concern, the National Association of REALTORS® offers these resources to help facilitate the understanding and implementation of proper listing content management.

The purpose of these resources is to assist brokers, agents, and multiple listing services in understanding the various assets they each control and how to secure and manage the contractual and intellectual property rights of the listing content.

  • What listing content can be protected?
  • Why manage and protect listing content?
  • How to manage and protect listing content
  • Flow of Rights and Building the Chain of Ownership
  • How to Build a Chain of Ownership
  • Related MLS Policy
  • Understanding the Terminology
  • Copyright Registration
  • MLS Compilation Registration
  • Sample Documents and Implementation Guides


Additional Resources

Automated Valuation Models
MLSs are now required to supply participants with the information necessary to create Automated Valuation Models.

Internet Data Exchange (IDX)
IDX policy gives MLS participants the ability to authorize limited electronic display of their listings by other participants.

Real estate professionals must be cognizant of copyright issues when it comes to listing content, most notably in connection with listing photographs.

Conference Live
NAR Conference Live is your virtual window into the 2019 REALTORS® Conference & Expo experience! Watch recaps, interviews and more.