Multiple Listing Service
A database shared among real estate brokers listing properties for sale, enabling cooperation between buyer's and seller's agents across a local market.
What is Multiple Listing Service?
A Multiple Listing Service (MLS) is a private database established by a regional real estate board or association that allows member brokers to share property listing information with one another. When a seller lists a property with a member broker, that listing is entered into the MLS and becomes accessible to all participating buyer's agents in the area, dramatically expanding the property's exposure. MLS listings contain detailed property information: address, list price, square footage, bed/bath count, lot size, school district, photos, days on market, and agent contact information. The MLS also records sold data—final sale prices and days on market for closed transactions—which form the data foundation for comparative market analyses (CMAs) and formal appraisals. Public-facing real estate platforms like Zillow, Redfin, and Realtor.com are powered by MLS data feeds (via IDX licensing agreements) but typically display listings with a 15-minute to 24-hour delay compared to direct MLS access. There are approximately 600 individual MLSs operating in the US, with limited data sharing between regions.
Example
When a homeowner lists with an agent in the Chicago metro area, the property is entered into MRED (Midwest Real Estate Data), the regional MLS covering 6 states and nearly 50,000 members. Within hours, every member agent in the region—and by extension, their buyer clients—can see the listing. A buyer's agent in suburban Chicago immediately sets up a client alert that triggers whenever a new property matching specific criteria hits the MLS, allowing their buyer to schedule a showing the same day the property goes live.