Sellers Left $1.5 Billion on the Table Over Three Years by Using Dual Agents, Study Finds

Private listings and dual-agent transactions can be costly to home sellers, with those in California, Florida, New York, and New Jersey losing the most, according to a new study.

Over the last three years, homes sold as private listings, which don't appear on a Multiple Listing Service, typically sold for 1.3% less than comparable sales on the MLS, costing the seller an average of $4,230 per sale, the analysis by Zillow found.

And sellers in dual-agent transactions, where one agent represents both buyer and seller, typically lost out on $2,165 per transaction during the same time period, the analysis found.

Over the three years covered by the study, home sellers who used dual agency lost a combined $1.49 billion, while sellers who listed privately lost a total of $1.36 billion, according to the study.

Private listings, also known as pocket or whisper listings, are homes marketed privately by a brokerage instead of or before a widely available MLS listing. (Realtor.com® recently struck an agreement with Zillow to show preview listings from brokers who participate in Zillow’s preview program, in an effort to boost market transparency.)

"Buyers searching without the right connections never even see the homes they're being shut out of," Mischa Fisher, chief economist at Zillow, said. "It's a velvet rope system designed to enrich brokerages, and sellers are subsidizing it."

Agent's incentives 'shift in dual agency'

The new Zillow study analyzed about 15 million transactions from 2023 to 2025, including 6.8 million dual-agent transactions and 6.2 million private listings. In both sets, the study excluded new-construction homes, foreclosures, auctions, and certain other conditions.

Comparing the sale price of the home to the company's in-house estimate of the home's value three months before the sale, the study determined the median percentage losses on each home.

The study suggests that the agent's incentives may shift in dual agency. Typically the buyer's agent and seller's agent split the commission, which often totals around 5% to 6% of the sales price, subject to negotiation.

But in dual agency, the dual agent gets a modest additional commission only if they negotiate the seller's price higher. Meanwhile, the dual agent stands to lose half of their prospective commission if they lose the listing to another buyer with independent representation.

Dual-agent deals cost California sellers an aggregate $533 million over the period in question, the study found. Sellers in Florida lost $217 million, New York sellers lost $146 million, and New Jersey sellers lost $115 million, according to the analysis.

Private listings delivered an even bigger hit to sellers on a per-home basis, the study found. And homes in lower price tiers lost the most, going for 2.2% less compared with similar MLS-listed homes, the study found.

"A private listing, by definition, is not widely marketed via the MLS, shrinking exposure to some potential buyers," says Realtor.com Chief Economist Danielle Hale. "This study shows that it reduces the price for sellers, and implies that some buyers are missing out on the chance to spot their dream home."

Because it excluded some important outliers, including sale prices under $10,000 or over $10 million, as well as some other kinds of transactions, Zillow says it likely underestimated the full financial hit sellers take from private listings and dual agency.

Growing concerns over private listings

The new research adds to the body of evidence raising questions about the potential drawbacks of private listings.

Bright MLS, a multiple listing service covering the mid-Atlantic region, recently published a study finding that private listings take longer to sell and offer no price benefits to the seller.

That study parsed six months of data on over 100,000 home sales spanning six states and Washington, DC, examining sales trends for private listings, also known as office exclusives.

"From our standpoint, the research says that, on average, when sellers list their home as an office exclusive in our market, the Bright MLS market, those homes take longer to sell; and they don't bring the seller any higher price," said Lisa Sturtevant, chief economist at BrightMLS.

Some state legislatures are examining the issue. In Washington state, Gov. Bob Ferguson recently signed a new law that will ban private listings there, marking the strictest ban in the country.

The law, which goes into effect on June 11, 2026, prohibits brokers from marketing homes to an exclusive or limited group of prospective buyers, unless the property is concurrently marketed to the public.

As well, Wisconsin last year passed restrictions on private listings that require brokers to obtain informed consent from sellers before marketing a home privately.

Lawmakers in Illinois, Hawaii, and Connecticut have also proposed similar legislation to restrict private listings.