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Published: December 18, 2024
If you’re a homeowner, it’s tempting to rely on tools like Zillow to check your home’s value. But the truth about Zillow estimates is that their accuracy varies significantly depending on your city and whether the home is actively listed or off-market. Active listings tend to provide more reliable results thanks to fresher data, while off-market homes often present challenges.
In this post, we’ll explore why Zillow’s estimates perform differently across cities and why consulting a real estate agent remains essential for an accurate valuation.
Key Takeaways
- Estimates are more reliable for active listings due to updated data and fresh comps.
- Accuracy varies by city due to market characteristics, transparency, and home uniformity.
- While these estimates provide a helpful starting point, they may not always reflect the true value—especially for off-market properties.
Why Estimates Are More Accurate for Active Listings
This blog will explain why Zillow estimates are more accurate for active listings compared to off-market homes, explore city-specific accuracy variations, and uncover the key factors behind these differences.
To support this, we’ve included two tables below sourced from Zillow’s Zestimate page ↗. These tables are a snapshot in time, accurate as of the blog’s publication date (see the top of this post). For your convenience, you can sort each column by clicking on the column header to view data in ascending or descending order.
Online estimators like Zillow’s Zestimate and Redfin’s Estimate rely on algorithms that blend public data, sales trends, and listing features. However, they have a significant advantage when a home is actively listed:
- More Data Points: Active listings provide updated photos, descriptions, square footage details, and specific improvements. This granular data helps refine the estimate.
- Recent Comparables (Comps): The algorithm pulls recently sold homes nearby to calculate the home’s value. For active listings, the surrounding market is fresh and dynamic.
- Seller Input: Sellers often add details not captured in public records—renovations, upgrades, or amenities—that influence the price.
For off-market homes, much of this information is missing or outdated. As a result, the estimator relies more heavily on historical data, which may not reflect the current condition or value of the home.
Home Value Estimates Vary by City—Examples and Speculation
Zillow’s estimates don’t perform equally well in all markets, and several factors can impact their reliability. In cities where estimates are considered highly accurate, the gap between the Zestimate and the actual sale price is typically small. This happens when there’s an abundance of recent, high-quality sales data.
Conversely, in cities with lower accuracy, estimates can be farther off the mark. This often occurs when data is incomplete, outdated, or when the housing market includes unique properties that are harder to evaluate.
The table below highlights examples of cities where estimates tend to perform well or less reliably, along with the likely reasons:
| City | Why Accuracy Tends to Be High | Why Accuracy Can Be Lower |
|---|---|---|
| San Francisco, CA | Dense recent sales data | Outliers skew upscale homes |
| Dallas, TX | Suburban uniformity helps | New developments mispriced |
| Chicago, IL | Well-documented markets | Aging inventory confuses data |
Why the Variation?
- Market Transparency: In markets with high turnover (like San Francisco), frequent sales provide estimators with better “comps” to analyze.
- Home Uniformity: Suburban neighborhoods with similar homes (like in Dallas) are easier for algorithms to predict. In contrast, unique or customized properties often throw off the estimate.
- Data Gaps: Older homes in areas like Chicago may have limited digital records, making estimators rely on outdated or incomplete information.
When checking your estimate, keep in mind how your city’s market characteristics might influence its accuracy.
Tables: Snapshot of Zillow’s Accuracy Data
Below are two tables sourced from Zillow’s Zestimate page as of this blog’s publication date. Table 1 and Table 2 contain data for active listings and houses that are off-market, respectively, for major metropolitan areas in the United States.
The definition of each column is as follows:
- Metropolitan Areas: Major metropolitan ↗ area in the United States.
- Median Error: For the Zestimate, half of all active homes are within the median error versus the selling price, and half are not.
- Home With Zestimates: Number of homes in the area that have a Zillow estimate.
- Within 5% of Sales Price: Percentage of transactions for which the Zestimate was within 5% of the transaction price.
- Within 10% of Sales Price: Percentage of transactions for which the Zestimate was within 10% of the transaction price.
- Within 20% of Sales Price: Percentage of transactions for which the Zestimate was within 20% of the transaction price.
Extreme Examples: Pittsburgh vs. Colorado Springs
While tools like Zillow provide a quick estimate, their accuracy depends on the local market. For example:
- Pittsburgh, PA: For active listings, the Zestimate falls within 5% of the sale price only 67% of the time, and for off-market listings, accuracy drops to just 23%.
- Colorado Springs, CO: In contrast, estimates are much more reliable—falling within 5% of the sale price 91% of the time for active listings and 56% for off-market properties.
While it’s impossible to know Zillow’s exact methodology, here are a few reasons why these cities might stand out:
- Pittsburgh: The city’s housing market includes a mix of older homes, variable property conditions, and smaller, lower-value sales that may lack detailed, up-to-date records. Inconsistencies in public data and fewer comparables for certain neighborhoods likely make predictions more difficult.
- Colorado Springs: This market benefits from a higher percentage of newer, more uniform housing developments. Additionally, Colorado Springs has seen steady growth, with consistent sales activity providing fresh and reliable data for Zillow’s algorithms.
If you live in a city like Pittsburgh, where estimates are less reliable, a real estate agent can offer insights based on recent sales, neighborhood trends, and specific property details. Algorithms often struggle to interpret these subtle factors.
For those curious, sort through the tables below and compare your area’s performance. It might shed light on how much you can trust those estimates—or not! Don’t see your metropolitan area in the table? Go to Contact Us and provide the name of your area that you want to include in the Zillow blog, and we’ll add it to the tables.
Active Listings
Click on a column header to sort the data in ascending or descending order.
| Metropolitan Areas | Median Error | Homes With Zestimates | Within 5% of Sales Price | Within 10% of Sales Price | Within 20% of Sales Price |
|---|---|---|---|---|---|
| Atlanta | 2.02% | 25.2 K | 82.43% | 94.14% | 98.12% |
| Austin | 2.34% | 14.2 K | 80.78% | 94.29% | 98.62% |
| Baltimore | 2.04% | 7.4 K | 77.03% | 90.51% | 95.38% |
| Boston | 2.53% | 10.9 K | 75.22% | 93.24% | 98.97% |
| Charlotte | 1.89% | 10.4 K | 82.75% | 94.65% | 98.22% |
| Chicago | 2.25% | 38.3 K | 79.49% | 93.53% | 98.29% |
| Cincinnati | 2.51% | 6.5 K | 75.40% | 92.75% | 98.22% |
| Cleveland | 3.04% | 5.8 K | 69.18% | 89.50% | 97.13% |
| Colorado Springs | 1.46% | 3.6 K | 91.09% | 97.92% | 99.51% |
| Dallas-Fort Worth | 2.00% | 26.3 K | 81.96% | 94.36% | 98.43% |
| Denver | 1.55% | 11.8 K | 88.25% | 97.52% | 99.57% |
| Detroit | 2.63% | 12.6 K | 72.75% | 89.89% | 96.59% |
| Fort Collins | 1.52% | 1.5 K | 89.36% | 97.38% | 99.03% |
| Houston | 2.23% | 30.8 K | 81.07% | 94.35% | 98.40% |
| Jacksonville | 2.13% | 8.9 K | 81.95% | 94.01% | 98.46% |
| Kansas City | 2.41% | 6.9 K | 75.81% | 91.92% | 97.53% |
| Las Vegas | 2.04% | 14.6 K | 85.68% | 96.07% | 98.73% |
| Los Angeles-Long Beach-Anaheim | 2.16% | 28.0 K | 79.23% | 93.95% | 98.87% |
| Miami-Fort Lauderdale | 2.48% | 50.5 K | 78.08% | 93.41% | 98.38% |
| Minneapolis-St Paul | 1.91% | 11.1 K | 83.99% | 95.98% | 99.16% |
| Nashville | 2.07% | 9.8 K | 81.72% | 93.87% | 98.09% |
| New York | 2.75% | 55.8 K | 71.99% | 90.74% | 97.87% |
| Orlando | 2.10% | 14.9 K | 84.56% | 95.68% | 98.98% |
| Philadelphia | 2.71% | 18.3 K | 71.48% | 89.01% | 96.19% |
| Phoenix | 1.92% | 24.7 K | 86.96% | 96.61% | 99.16% |
| Pittsburgh | 3.00% | 7.2 K | 66.91% | 86.54% | 95.71% |
| Portland | 1.82% | 8.5 K | 84.98% | 95.84% | 99.29% |
| Raleigh | 1.82% | 4.1 K | 85.11% | 95.87% | 98.80% |
| Riverside | 1.85% | 20.2 K | 82.15% | 93.37% | 97.19% |
| Sacramento | 2.09% | 9.0 K | 82.67% | 94.74% | 98.64% |
| San Antonio | 2.21% | 13.8 K | 79.70% | 92.71% | 97.57% |
| San Diego | 2.04% | 8.1 K | 82.18% | 95.05% | 98.68% |
| San Francisco | 3.11% | 10.1 K | 67.07% | 87.46% | 97.62% |
| Seattle | 2.11% | 9.1 K | 82.53% | 94.85% | 98.97% |
| St. Louis | 2.86% | 8.2 K | 69.79% | 89.31% | 97.62% |
| Tampa | 2.29% | 22.4 K | 82.84% | 94.90% | 98.60% |
| Tucson | 1.81% | 4.3 K | 84.05% | 95.71% | 98.68% |
| Washington | 1.66% | 15.2 K | 85.08% | 96.14% | 99.04% |
Off Market
Click on a column header to sort the data in ascending or descending order.
| Metropolitan Areas | Median Error | Homes With Zestimates | Within 5% of Sales Price | Within 10% of Sales Price | Within 20% of Sales Price |
|---|---|---|---|---|---|
| Atlanta | 6.76% | 1.97 M | 38.86% | 64.92% | 85.47% |
| Austin | 6.69% | 706.0 K | 39.57% | 65.87% | 88.81% |
| Baltimore | 6.52% | 891.0 K | 41.54% | 63.70% | 81.98% |
| Boston | 6.95% | 1.45 M | 37.35% | 65.18% | 87.92% |
| Charlotte | 6.51% | 1.01 M | 40.23% | 65.74% | 85.24% |
| Chicago | 8.03% | 3.02 M | 33.81% | 58.34% | 82.76% |
| Cincinnati | 8.97% | 730.1 K | 31.10% | 54.17% | 77.87% |
| Cleveland | 10.27% | 716.3 K | 26.92% | 49.12% | 75.20% |
| Colorado Springs | 4.37% | 248.1 K | 55.79% | 81.12% | 94.28% |
| Dallas-Fort Worth | 5.98% | 2.15 M | 43.46% | 70.45% | 89.64% |
| Denver | 5.17% | 959.9 K | 48.67% | 76.12% | 93.39% |
| Detroit | 8.66% | 1.46 M | 32.66% | 54.69% | 78.20% |
| Fort Collins | 5.16% | 128.4 K | 48.84% | 71.84% | 90.54% |
| Houston | 6.40% | 2.08 M | 41.27% | 67.47% | 87.66% |
| Jacksonville | 6.84% | 598.0 K | 39.61% | 64.70% | 85.93% |
| Kansas City | 7.36% | 732.8 K | 36.60% | 61.34% | 83.33% |
| Las Vegas | 5.08% | 743.4 K | 49.25% | 76.40% | 93.06% |
| Los Angeles-Long Beach-Anaheim | 6.38% | 2.95 M | 40.85% | 67.93% | 89.15% |
| Miami-Fort Lauderdale | 7.33% | 2.21 M | 36.15% | 62.24% | 86.09% |
| Minneapolis-St Paul | 6.05% | 1.23 M | 42.60% | 69.80% | 89.70% |
| Nashville | 7.02% | 731.3 K | 37.76% | 62.98% | 83.72% |
| New York | 8.24% | 5.04 M | 33.01% | 57.58% | 82.60% |
| Orlando | 5.84% | 880.7 K | 43.59% | 71.28% | 90.30% |
| Philadelphia | 8.57% | 1.96 M | 32.58% | 55.43% | 79.60% |
| Phoenix | 6.02% | 1.58 M | 43.02% | 70.16% | 90.83% |
| Pittsburgh | 12.65% | 773.1 K | 23.05% | 42.15% | 65.80% |
| Portland | 5.74% | 775.6 K | 44.48% | 71.40% | 89.77% |
| Raleigh | 5.61% | 465.9 K | 45.35% | 73.53% | 91.26% |
| Riverside | 6.18% | 1.34 M | 42.61% | 67.20% | 84.89% |
| Sacramento | 5.95% | 732.7 K | 43.23% | 72.20% | 90.57% |
| San Antonio | 6.65% | 808.3 K | 39.57% | 64.91% | 85.71% |
| San Diego | 6.25% | 865.0 K | 41.37% | 68.31% | 89.36% |
| San Francisco | 6.92% | 1.26 M | 38.64% | 65.34% | 88.85% |
| Seattle | 6.37% | 1.20 M | 39.98% | 68.94% | 90.30% |
| St. Louis | 9.19% | 946.4 K | 30.01% | 53.68% | 77.64% |
| Tampa | 7.21% | 1.20 M | 36.93% | 63.08% | 86.25% |
| Tucson | 6.28% | 356.5 K | 42.08% | 68.53% | 88.27% |
| Washington | 5.11% | 1.88 M | 49.36% | 75.36% | 91.90% |
Final Thoughts
Online estimators like Zillow and Redfin are powerful tools for homeowners and buyers alike, but their accuracy depends on a range of factors. Whether you’re checking your home’s value for fun or considering a sale, use these tools as just one piece of the puzzle, not the entire picture.
For a more reliable picture, especially if you’re planning to sell or buy, consult with a local real estate agent. Agents have access to up-to-date market data and can provide a tailored, in-depth analysis of your home’s true value.
For more information about selling your home, see The True Costs of Selling Your Home: What You Need to Know.