How Accurate Is the Zillow Zestimate in Seattle?

If you own a home in Seattle, Zillow probably already has an estimate of what it’s worth. But if you’re thinking about selling, how close is that Zestimate to what your home might actually sell for?

Zillow describes its Zestimate as a starting point, not an appraisal, and says its accuracy depends partly on the data available for a home and its market. Zillow’s own figures also show an important difference between homes that are already listed and those that are still off the market.

To see how that plays out for Seattle homeowners, HomeLight compared pre-listing Zestimates with the eventual sale prices of 29 recently sold homes in the city.

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How accurate is the Zillow Zestimate in Seattle?

Zillow publishes separate Zestimate accuracy statistics for homes that are on the market and those that are off the market. That distinction matters if you’re checking your home’s value before deciding whether to sell.

Current Zillow Group data for the Seattle metro reports the following:

Source: Zillow.com, last refreshed Nov. 8, 2026

The off-market numbers are particularly relevant to homeowners who haven’t listed yet. Just 42.91% of Seattle-area off-market Zestimates fall within 5% of the closed sale price, according to Zillow Group’s published data.

Once a home goes on the market, Zillow has more information to work with. Its model can incorporate the asking price, listing description, comparable homes, and days on market, in addition to public records and other property data. That helps explain why Zillow reports significantly lower errors for listed homes.

For active listings, Zillow measures accuracy by comparing the last Zestimate shown before a home goes pending with the final recorded sale price. For our HomeLight analysis, we wanted to answer a different question: How close was the Zestimate before the home was listed and Zillow had that additional market information?

What does a 6.09% median error mean in dollars?

A 6.09% median error can translate into a meaningful dollar amount at Seattle home prices.

This doesn’t mean a $1 million Zestimate will necessarily be within $60,900 of the sale price. A median error of 6.09% means half of measured errors are smaller and half are larger. Individual Zestimates can be much closer or farther from the eventual sale price.

We tested Seattle Zestimates against actual sales

To see how pre-listing Zestimates performed in Seattle, HomeLight reviewed 29 homes that recently sold within Seattle city limits.

For each property, we compared the last available Zestimate before the home was listed for sale with its final closed sale price. We then calculated the percentage difference and noted whether Zillow estimated the home above or below its final sale price.

This approach differs from Zillow’s published on-market accuracy measurement. Our goal is to approximate the position of a homeowner who checks Zillow while the home is still off the market.

Zillow says historical Zestimates are based on information available at that point in time. The company notes that it can occasionally recalculate historical Zestimates following major model or data updates, but says future transaction information isn’t used to influence an earlier historical estimate.

Methodology: HomeLight reviewed 29 recently sold homes within Seattle city limits. For each property, we compared the last historical Zestimate available before the home was listed for sale with its final closed sale price, then calculated the absolute percentage difference between the two. This sample is illustrative and is not statistically representative of all Seattle homes.

What our Seattle Zestimate test found

Among the 29 recently sold Seattle homes HomeLight reviewed, the median absolute percentage error between the pre-listing Zestimate and sale price was 5.4%. The median absolute dollar difference was $51,100.

Just under half of the Zestimates — 48.3% — came within 5% of the final sale price. About 86.2% were within 10%, and all 29 were within 20%.

Zillow’s estimate came in higher than the final sale price for 16 homes and lower for 12. One Zestimate matched the home’s sale price exactly.

The results also showed a wide range from one property to another. The closest Zestimate in our sample was right on the sale price, while the largest miss was 18.2%, or $200,000 above what the home ultimately sold for.

For comparison, Zillow Group reports a 6.09% median error for off-market homes across the Seattle metro, with 42.91% falling within 5% of the sale price.

Five Seattle Zestimate examples

To show what the differences looked like in actual dollars, we selected five homes from our sample representing the closest estimate, the lower quartile, the median result, the upper quartile, and the largest miss.

A positive difference means the pre-listing Zestimate was higher than the eventual sale price. A negative difference means the Zestimate was lower.

How does Zillow calculate a Zestimate?

Zillow says its Zestimate is an automated estimate of a home’s market value, not an appraisal. Its current neural network-based model analyzes hundreds of data points and draws from sources that include county and tax assessor records, MLS feeds, and information supplied by homeowners.

The model considers details such as square footage, location, bedrooms and bathrooms, previous sales, tax assessment, and market trends. Once a property is listed, Zillow can also use information including the asking price, listing description, comparable properties, and days on market.

And as with any real estate value estimate, the quality and completeness of that information can affect the final result. This is even true for professional appraisals.

Why can a Seattle Zestimate be off?

A Zestimate may know a home’s square footage and bedroom count without knowing everything that makes buyers value one Seattle property differently from another.

Renovations and condition can be difficult to capture. Zillow says unreported additions, updates and remodels may not be reflected in its estimate. A remodeled kitchen, updated systems or significant deferred maintenance can all make two otherwise similar homes very different in the eyes of buyers.

Property-specific features can matter. Views, lot usability, street location, walkability scores, interior condition, and the quality of improvements aren’t always apparent in public records.

Comparable homes aren’t always interchangeable. Automated valuation models rely heavily on available property and market data. A home that is unusual for its area or has relatively few comparable recent sales may be harder to estimate. Zillow says the amount of reliable data available for a property and surrounding area directly affects Zestimate accuracy.

These differences are one reason an online estimate can be useful without necessarily being the number a seller should use to price a home.

Get another estimate using details about your home

When you’re estimating what your home might sell for, it can help to compare more than one valuation, especially when the numbers disagree.

HomeLight’s Home Value Estimator takes a somewhat different approach. In addition to pulling property, sales, and market data, the tool asks eight questions designed to capture more specific information about the home itself.

The questions allow you to enter and confirm the property address, beds and baths, kitchen, bathrooms, and main living space, as well as your home’s curb appeal, upgrades and extras, and your selling timeline.

Those questions can capture details that may not be apparent from an automated estimate based primarily on existing property and market data. For example, public records may show that two homes have identical bed and bath counts without reflecting that one has a recently remodeled kitchen or newer HVAC system.

HomeLight describes its estimate as a starting point, too. Homeowners can also receive a free introduction to a top 5% agent in their ZIP code who can look at the property, comparable sales, and current buyer demand. With this information, an agent can provide a comparative market analysis (CMA), which estimates your home’s value based on local sales of similar homes and market conditions.

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Comparing the HomeLight estimate with a Zestimate can be useful even when the two numbers are close. If several valuation methods land in roughly the same range, they’re generally pointing in the same direction. If they’re far apart, the property may deserve a closer look.

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What if your Seattle Zestimate looks wrong?

If your Zestimate seems noticeably higher or lower than expected, first check the property information Zillow is using. Zillow recommends reviewing home facts and correcting incomplete or inaccurate information. It also notes that updates may not always change the Zestimate.

You can also:

1. Compare another estimate. Run the address through another home value estimator to see whether the Zestimate is an outlier.
2. Review recent comparable sales. Look for homes that are similar in location, size, age, style, and condition.
3. Ask a local agent for a comparative market analysis. An agent can consider features and current competition that an automated model may miss. Most agents will perform a CMA for free, though some may charge a small fee.
4. Correct inaccurate home facts on Zillow. If Zillow has the wrong square footage, bed or bath count, or other property details, claim your home and update the information. Zillow says those changes can affect the Zestimate, although not every update will change the value. For other property-data problems, you can visit Zillow’s Help Center or Customer Support.
5. Get an appraisal when you need a formal valuation. Zillow itself states that a Zestimate is not an appraisal and can’t replace one. According to Angi, most homeowners pay $314 to $425 for a home appraisal, with a national average of $359.

Is a Zestimate enough to price your Seattle home?

A Zillow Zestimate can give Seattle homeowners a quick estimate of value, but its own accuracy data shows why the number shouldn’t automatically become a listing price.

In HomeLight’s 29-home Seattle sample, the median pre-listing Zestimate differed from the eventual sale price by 5.4%, reinforcing that a Zestimate can be informative but shouldn’t be treated as a definitive pricing tool.

If you’re considering selling, compare your Zestimate with another estimate and recent comparable sales. HomeLight’s Home Value Estimator can provide another perspective by factoring in answers about the condition and features of your home, while a local agent can provide a more detailed opinion based on the property and today’s Seattle market.

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