Seattle Construction Permit Index, September 2026: 91.5
The City of Seattle issued 455 construction permits in September 2026, which puts the Builtie Construction Permit Index for Seattle at 91.5 (its average month, January to September 2025 = 100), up 0.2% on September 2025 and down 11.8% on August 2026.
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September 2026 at a glance
| Measure | September 2026 |
|---|---|
| Index (base = 100) | 91.5 |
| Permits issued | 455 |
| Change on August 2026 | -11.8% |
| Change on September 2025 | +0.2% |
| Base: average month | 497 |
| Three-month average | 99.1 |
| Three-month average, change on a year earlier | +2.8% |
The three months to September 2026 averaged 99.1, up 2.8% on the same three months a year earlier.
Average month, January to September 2025 = 100. Gaps are months below the publish rule. Permits read October 9, 2026.
Month by month
| Month | Permits issued | Index | Month over month | Year over year | Note |
|---|---|---|---|---|---|
| September 2026 | 455 | 91.5 | -11.8% | +0.2% | |
| August 2026 | 516 | 103.7 | +1.6% | +7.3% | |
| July 2026 | 508 | 102.1 | -5.4% | +0.8% | |
| June 2026 | 537 | 108.0 | +12.8% | -2.5% | |
| May 2026 | 476 | 95.7 | -15.3% | -16.6% | |
| April 2026 | 562 | 113.0 | -8.0% | +0.7% | |
| March 2026 | 611 | 122.8 | +59.5% | +14.6% | |
| February 2026 | 383 | 77.0 | -13.5% | -3.0% | |
| January 2026 | 443 | 89.1 | -10.7% | +3.0% | |
| December 2025 | 496 | 99.7 | +40.9% | n/a | |
| November 2025 | 352 | 70.8 | -28.5% | n/a | |
| October 2025 | 492 | 98.9 | +8.4% | n/a | |
| September 2025 | 454 | 91.3 | -5.6% | n/a | |
| August 2025 | 481 | 96.7 | -4.6% | n/a | |
| July 2025 | 504 | 101.3 | -8.5% | n/a | |
| June 2025 | 551 | 110.8 | -3.5% | n/a | |
| May 2025 | 571 | 114.8 | +2.3% | n/a | |
| April 2025 | 558 | 112.2 | +4.7% | n/a | |
| March 2025 | 533 | 107.1 | +34.9% | n/a | |
| February 2025 | 395 | 79.4 | -8.1% | n/a | |
| January 2025 | 430 | 86.4 | n/a | n/a |
The base is Seattle's average month over January to September 2025, the months on record in the base year: 497 permits.
What was permitted
Permits Builtie could classify by building type and work, for September 2026 and for the twelve months to it. Permits with no building type, demolitions and unclassified work are counted in the index but not here.
| Building type and work | Permits, September 2026 | Share, September 2026 | Share, Oct 2025 to Sep 2026 |
|---|---|---|---|
| Residential Renovation | 218 | 53% | 54% |
| New Residential Construction | 104 | 25% | 25% |
| Commercial Renovation | 77 | 19% | 17% |
| Institutional Renovation | 7 | 2% | 3% |
| Industrial Renovation | 3 | 1% | 1% |
| New Commercial Construction | 1 | 0% | 0% |
| New Institutional Construction | 1 | 0% | 0% |
| New Industrial Construction | 0 | 0% | 0% |
How Seattle compares
Seattle is one of the 15 markets in the composite Builtie Construction Permit Index. Among the 17 markets indexed for September 2026, Seattle ranks 9 of 17 on year-over-year change.
What the Seattle data covers
Seattle's feed rarely names the builder: 1.4% of new-build permits carry one. Builtie resolves the company behind a Seattle project from other records, and does not publish a Seattle builder count because it would describe the feed rather than the market.
More on Seattle: Seattle construction permits by month; the September 2026 permit report; Seattle construction leads by trade.
How to cite
Builtie Construction Permit Index, Seattle, September 2026, builtie.com/seattle-construction-permit-index/.
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Frequently asked questions
What is the Seattle construction permit index for September 2026?
91.5 (average month, January to September 2025 = 100), from 455 permits issued. Released October 15, 2026 by Builtie.
Is construction in Seattle up or down?
By permits issued, September 2026 was up 0.2% on September 2025 and down 11.8% on August 2026. The three months to September 2026 averaged 99.1, up 2.8% on the same three months a year earlier.
How is the index calculated?
Permits issued in the month, divided by Seattle's average month over January to September 2025, the months on record in the base year, times 100. A month counts only with 40 or more permits and at least half the market's median month.
Where does the data come from?
The City of Seattle's own building permits, read by Builtie October 9, 2026.
What does Builtie cost?
Starter is $79 per seat per month (CAD) for 20 projects; Growth is $99 for 50 projects and adds LinkedIn and email outreach. There is a 7-day free trial with 10 projects.