Zillow Accuracy: How Reliable Are Property Estimates Really?

When you type your address into Zillow, a popular online home value estimator used by millions in the U.S. to get quick property estimates. Also known as Zestimate, it’s often the first thing people check before listing a home or making an offer. But here’s the thing: Zillow accuracy isn’t the same everywhere. In dense urban areas with lots of recent sales data, it can be surprisingly close—sometimes within 5% of the actual sale price. In rural towns, new developments, or places with outdated tax records? It can be off by 20%, 30%, or more. That’s not a small mistake—it’s thousands of dollars in potential missteps.

Why does this happen? Zillow doesn’t send agents to measure your house. It uses algorithms that pull public records, past sales, school zones, and sometimes even satellite imagery. But if your home had a renovation that wasn’t permitted, or if your neighborhood just saw a wave of new construction that hasn’t been logged yet, Zillow won’t know. It’s not lying—it’s just working with incomplete or outdated data. And that’s a big problem if you’re using it to set your listing price, make an offer, or decide whether to refinance. Real estate agents in places like Austin, Virginia, or Melbourne know this. They check Zillow, sure, but they also cross-reference it with MLS data, recent comparable sales, and local market trends. Zillow is a starting point, not a final answer.

Some people treat Zillow like a crystal ball. Others dismiss it entirely. The truth is in the middle. If you’re a first-time buyer, it’s useful to get a rough sense of what homes in your target area cost. If you’re a landlord in Maryland or a seller in Texas, it’s worth comparing Zillow’s number to what your agent says—especially if there’s a gap of more than 10%. And if you’re researching commercial property in Australia or affordable housing in Fairfax County, Zillow won’t even help you there—it’s built for single-family homes in the U.S. The posts below show real examples of how property values are measured, where estimates go wrong, and how to find trustworthy data instead. You’ll see what actually drives value, how to verify claims, and why the best decisions come from knowing more than just an algorithm’s guess.