How accurate are Colorado price ranges?
Every Colorado figure labelled "Price range" on Groundwork passed a sealed test before it was shown: we priced real sales using only data from before each sale, then compared. Figures labelled "Rough estimate" did not reach that standard; their measured miss is listed too. Where a county's test failed outright, its parcels show no figure.
Tested price ranges
Half within: half of the test sales came within this much of our estimate (the median miss). Inside the range: the share of scored test sales that fell inside the printed range. A range whose final check is not passed by its due date is withdrawn (the parcel then shows facts only).
| County | Priced | Test | Test sales from | Test sales | Half within | Inside the range | Parcels with this range | Final check |
|---|---|---|---|---|---|---|---|---|
| Jefferson County | single-family homes | Sealed home-value test (co-homevalue-1) | Jan–Sep 2026 | 753 | ±10% | 75% | 152,303 | Due Jun 30, 2027 |
| Denver County | single-family homes | Sealed home-value test (co-homevalue-1) | Jan–Sep 2026 | 5,145 | ±9% | 76% | 133,314 | Due Jun 30, 2027 |
| Boulder County | single-family homes | Sealed home-value test (co-homevalue-1) | Jan–Sep 2026 | 2,723 | ±9% | 75% | 73,324 | Due Jun 30, 2027 |
| Mesa County | single-family homes | Sealed home-value test (co-homevalue-1) | Jan–Sep 2026 | 1,667 | ±7% | 79% | 41,979 | Due Jun 30, 2027 |
| Denver County | condominiums | Sealed home-value test (co-homevalue-1) | Jan–Sep 2026 | 1,289 | ±10% | 84% | 32,370 | Due Jun 30, 2027 |
| Arapahoe County | condominiums | Sealed home-value test (co-homevalue-1) | Jan–Sep 2026 | 804 | ±8% | 77% | 22,084 | Due Jun 30, 2027 |
| Eagle County | single-family homes | Sealed home-value test (co-homevalue-1) | Jan–Sep 2026 | 485 | ±10% | 81% | 13,371 | Due Jun 30, 2027 |
| Denver County | single-family homes (dearest tenth) | Sealed home-value test (co-homevalue-1) | Jan–Sep 2026 | 501 of the 5,145 | ±9% | 75% | 12,687 | Due Jun 30, 2027 |
| Boulder County | condominiums | Sealed home-value test (co-homevalue-1) | Jan–Sep 2026 | 546 | ±7% | 87% | 12,682 | Due Jun 30, 2027 |
| Denver County | condominiums (least expensive tenth) | Sealed home-value test (co-homevalue-1) | Jan–Sep 2026 | 181 of the 1,289 | ±12% | 79% | 6,101 | Due Jun 30, 2027 |
| Denver County | condominiums (dearest tenth) | Sealed home-value test (co-homevalue-1) | Jan–Sep 2026 | 130 of the 1,289 | ±11% | 81% | 3,477 | Due Jun 30, 2027 |
Rough estimates
Where a county's own sales were too few for a sealed test, or its test missed our standard but stayed usable, the card says "Rough estimate" and gives the miss measured where it was measured: in the county, or across the state's pooled sales. Each label says what it was tested on and how close its estimates came.
| Miss measured | Half within | Covers | Parcels |
|---|---|---|---|
| El Paso County | ±6% | Land and building | 179,113 |
| Arapahoe County | ±7% | Land and building | 137,681 |
| Douglas County | ±6% | Land and building | 98,463 |
| Weld County | ±6% | Land and building | 79,077 |
| Jefferson County | ±7% | Land and building | 28,587 |
| Jefferson County | ±10% | Land and building | 15,028 |
| Teller County | ±9% | Land and building | 12,488 |
| Gunnison County | ±11% | Land and building | 10,824 |
| Elbert County | ±7% | Land and building | 9,421 |
| Mesa County | ±9% | Land and building | 7,945 |
| El Paso County | ±11% | Land and building | 4,514 |
| Denver County | ±15% | Land and building | 4,095 |
| Mesa County | ±16% | Land and building | 3,747 |
| Eagle County | ±10% | Land and building | 3,035 |
| Weld County | ±15% | Land and building | 2,906 |
| Boulder County | ±5% | Land and building | 1,871 |
| Arapahoe County | ±8% | Land and building | 1,595 |
| Boulder County | ±7% | Land and building | 793 |
What did not pass
The home-value test (co-homevalue-1) checked 43 county and home-type groups on 38,947 sealed sales: 8 passed for a price range, 13 passed only as a rough estimate, and 22 passed neither, so they show no tested home value from it.
In the groups that passed, 1,897 homes got no range because their whole range fell below $50,000 (the test scored only home sales of $50,000 or more).
In Weld County, 112 homes got no range because the county's value for them changed after the test ran (accounts that are not the parcel's own land and buildings were taken out of its value).
Sources and dates
Test sales: recorded Colorado sales on file for each county. Test figures: our out-of-time test reports and, where run, sealed final checks (co-homevalue-1). Parcel counts: our Colorado map on Oct 25, 2026. Estimates are for your own analysis, not an appraisal or a broker price opinion.