4 Reasons Why You Shouldn’t Believe Online Home Value Estimates

"Those online estimates are simply that: estimates" | Barbara Bellesi Zito


My husband and I browse real estate listings occasionally, but we’re perfectly content to stay where we are until both the market and mortgage rates behave themselves again. 


For kicks, we recently checked out the estimated value of one very interesting listing: our own home. The number surprised us both. “Should we call a real estate agent and start packing?” my husband asked.


We came to our senses, of course, fully aware that those online estimates are simply that: estimates. But if this particular site were indeed to be believed, our house was worth $122,000 more than what we bought it for seven years ago. Another listing site pulled up the same figure, while a third offered a more conservative estimate, which was still $68,000 more than what we paid.


I did reach out to a few real estate agents, not to list our home, but to get their advice on whether anyone should believe those online home value estimates. Here’s why they think you should take what you see with a proverbial grain of salt...

June 14, 2026
Can I Trust the ‘Zestimate’ for My Home on Zillow? | New York Times Real Estate Q&A Pretty remarkable statement in the middle of this short article: A Sotheby's agent is quoted as saying, "He has never heard of a tax assessor relying on a Zestimate." Don't rely on algorithmic valuations for your property's value. These estimates are interesting, but anything but the final word. Read the paywalled article on NYTimes.com >
3 reasons online home value estimates fail
April 13, 2026
Why Your Zillow Estimate is Wrong | What Your Home is Actually Worth | Pauly Campanaro Discover the 3 reasons online home value estimates fail: they can't account for condition (your $40K kitchen remodel), they lag behind the market (using 60-90 day old data), and they don't know your competition (what's hitting the market this week). Learn why pricing right matters: homes priced correctly sell 19 days faster and for 3.8% more ($15K+ on a $400K home). Excerpted from this video posted by Pauly Campanaro:
Screenshot of a Twitter post by Ryan Lundquist, discussing a property's Zestimate history and price changes.
September 15, 2023
@SacAppraiser | Ryan Lundquist Zestimate history. This property in Roseville listed at $349K, and the Zestimate matched the list price at $349K despite comps being above $600K. After 11 days the price went to $699K (sold $638K). Today's Zestimate shows no history of $349K. Maybe a brief Zestimate gets erased?
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