CoStar and Realtor.com clash over number two US portal claim

A war of words is escalating between OnTheMarket owner CoStar and its rival Realtor.com in the US.

It comes as CoStar was forced to change some marketing claims by its Homes.com portal which said it was the number two property website in the US behind Zillow.

Realtor.com, which claims to be the second largest property portal in the US, challenged CoStar’s marketing and the National Advertising Division (NAD) of BBB National Programs has ordered Homes.com to alter its terminology, as originally reported by OnlineMarketPlaces.com.

CoStar’s advertising was found to be misleading because the monthly visitor figures it shares as part of its "we're number two" statistics were a combination of web traffic numbers to several other CoStar-owned websites.

The NAD decision said CoStar shouldn't use data based on combined traffic and said it can't accurately say that its visitor numbers are double Realtor.com's.

However, the notice said “nothing in these two decisions precludes CoStar from making other truthful and non-misleading claims about the number of unique visitors to its websites collectively, or to any of its individual websites, or comparative claims about Homes.com’s traffic.”

While CoStar has changed its messaging, it is still pretty unimpressed with Realtor.com.

A statement from Gene Boxer, CoStar Group general counsel, provided to Estate Agent Today, claimed Realtor.com is now “sliding into obscurity.”

Boxer highlighted data showing  that the Homes.com Network had 156m unique monthly visitors in March 2024 and that Homes.com had 110m as shown by Google Analytics.

In contrast, Realtor.com reported only 66m unique monthly users in the same period, measured by Adobe Analytics.  

The statement added: “As a result, Homes.com is the #2 most-visited residential real estate portal, far surpassing Realtor.com, and the Homes.com Network has double the traffic of Realtor.com.  Apples to apples, Realtor.com is losing the portal wars, and losing big. 

“Consistent with NAD’s decision, CoStar will continue to advertise that fact and disclose the number of unique visitors to the Homes.com Network and Homes.com.  Realtor.com’s NAD gambit can’t change those numbers, or the reality: Realtor.com has fallen far behind.  

“Realtor.com keeps trying, and keeps failing, to hide the facts.  We couldn’t be happier to continue spreading the word about the success of Homes.com, and in compliance with the NAD’s recommendation, the success of the Homes.com Network.”