From Straight Arrow · · 1m 40s
Home value estimates don't match reality
Zillow's home value estimates swing wildly, but real estate agents say they don't reflect actual sales.
In brief
Zillow's home value estimates swing wildly, but real estate agents say they don't reflect actual sales. Zillow's home value estimates can differ by up to $1 million overnight due to ZIP code averaging, but agents warn lenders won't approve loans based solely on these figures. Originally reported by Straight Arrow.
Zillow's home value estimates
Zillow's home value estimates are snapshots in time that don't match actual home sales prices.
“A Zestimate is a snapshot in time, going backwards”
Why estimates differ from reality
Real estate agents say Zillow groups neighborhoods together and uses public records, creating false price realities for homes.
“If a home does not match public records, Perna said it’s because of a myriad of reasons, including cities not inquiring about permit statuses and people not pulling permits”
Zillow's error rates
Zillow has a 7.2% error rate for off-market homes and 2.54% in San Francisco, the highest error rate among top markets.
“San Francisco has the highest error rate of Zillow’s top markets at 2.54%, and Colorado Springs has the lowest at 1.11%”
Agents' concerns
Real estate agents warn that Zillow's estimates can swing by up to $1 million overnight due to ZIP code-level averaging.
“We've had Zestimates on properties swing upwards to $1 million overnight”
Lenders won't use app values
Most lenders won't approve loans based solely on automated valuation reports from real estate apps.
“Both realtors agreed that knowing how algorithmic the real estate apps work, sellers and buyers should continue to use it with caution”
Market conditions
Redfin reports 63% more sellers than buyers nationally, the widest gap since 2013, with home sales down 2.2% from September 2025.
“Redfin reported Wednesday that much of the U.S. is in a buyer’s market, with 63% more sellers than buyers, the widest gap since 2013”
When to sell
Real estate agents advise sellers to consider mortgage rates, home value, and personal needs when deciding whether to sell.
“Interest rates are going to come down in the middle 5s and sit there for a while”
Zillow's methodology
Zillow calculates home values using county and tax assessor records, MLS feeds, basic home characteristics, and market trends.
“Zillow spokesperson Alex Lacter said in an email to Straight Arrow that the company calculates values based on county and tax assessor records, feeds from multiple listing services (MLS), basic home characteristics, market trends and data”
Market slowdown
Home sales are starting to slow as mortgage rates rise and buyers face higher costs.
“People are not buying because they can’t negotiate for lower prices but because they cannot afford homes currently on the market”
What happens next
Sellers should use Zillow estimates cautiously and consider mortgage rates when deciding whether to sell their homes.
“Use it as a tool, but not the definitive tool in making an offer”
What matters most
Zillow's home value estimates can differ by up to $1 million overnight due to ZIP code averaging, but agents warn lenders won't approve loans based solely on these figures.
