Compass Analysis Links Zillow Exposure to Lower Sale Prices

Compass Analysis Links Zillow Exposure to Lower Sale Prices

Compass, Inc. has released internal research suggesting a correlation between exposure on Zillow and reduced final sale prices for home sellers. The study, led by the brokerage’s chief economist and chief data officer, analyzed nearly 300,000 listings to determine what the firm terms the “Zillow Tax.”

The data review covered 296,966 Compass listings posted between January 2025 and May 2026. Within that dataset, economists compared 806 listings that were restricted from appearing on Zillow Group, Inc. against those that were widely distributed on the portal. The findings indicate that properties kept off the platform achieved a median sale-to-list price ratio of 100%. Conversely, listings that appeared on Zillow secured a ratio of 98.7%, representing a 1.3% difference.

Quantile regression models confirmed the statistical significance of this 1.3 percentage point gap, with a margin of error of plus or minus 0.8 percentage points. In practical terms, Compass notes that on a property valued at $1 million, this disparity translates to approximately $13,000 less in seller proceeds. The report further highlights that 50.5% of the banned listings sold at or above their asking price, compared to 44.6% of the listings shared on the portal.

The release of these findings occurs against a backdrop of intensifying legal friction between the two real estate giants. The conflict originated last June following Zillow’s implementation of its Listing Access Standards policy. Compass subsequently filed an antitrust lawsuit alleging Zillow was leveraging monopoly power to damage competition, though that suit was voluntarily dismissed in March. Zillow has since counter-sued, accusing Compass and Midwest Real Estate Data (MRED) of conspiring to block data feeds to the Chicagoland MLS.

Currently, a House Judiciary subcommittee is investigating the private listing network partnership between Compass and MRED. Additionally, Compass has filed Code of Ethics complaints against Zillow in 26 states, 55 MLSs, and 30 realtor associations, accusing the portal of false advertising.

Market Snapshot

In afternoon trading, Compass, Inc. (COMP) was up 1.06% to $11.93, giving the company a market capitalization of $8.27 billion. Meanwhile, Zillow Group, Inc. (Z) traded down 0.69% to $33.42, with a market cap of $7.39 billion.

What to watch

• Updates on the House Judiciary subcommittee’s inquiry into the Compass-MRED partnership.
• Legal proceedings regarding Zillow’s counter-suit against Compass and MRED.
• Further responses from real estate associations regarding the filed ethics complaints.

Source: original release