B2B data
Construction Companies in Washington
Ken's database lists 5,436 construction companies headquartered in Washington as of Oct 17, 2026. The largest group, 61%, has 1-10 employees.
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Ken Search
Query
Industry: "Construction", excluding "Real Estate", "Utilities" and "Architecture and Planning"; HQ state: Washington; HQ country: United States; Employees on record: 1 or more
- Companies
- 5,436
- 1-10 employees
- 3,317 (61%)
- 11-50 employees
- 1,814 (33%)
- 51-200 employees
- 103 (2%)
Ken's database, Oct 17, 2026. Headquarters counts, refreshed weekly.
How Many Construction Companies Are in Washington?
In short 5,436 construction companies in Ken's database have their headquarters in Washington (Oct 17, 2026).
Ken's database lists 5,436 construction companies with headquarters in Washington. The largest group, 61%, has 1-10 employees. A company with only a branch office in Washington is not counted.
| Employees | Companies | Share |
|---|---|---|
| 1-10 | 3,317 | 61% |
| 11-50 | 1,814 | 33% |
| 51-200 | 103 | 2% |
| 201-500 | 7 | <1% |
| 501-1,000 | 1 | <1% |
| 1,001-5,000 | 2 | <1% |
| 10,001+ | 2 | <1% |
| Not listed | 190 | 3% |
| Total | 5,436 | 100% |
Employee range as listed on each company profile, for the companies in the count. Not listed means the profile shows no size.
Largest Construction Companies in Washington
In short By employee count in Ken's database, the largest is McKinstry in Seattle with 1,001-5,000 employees.
| Company | City | Employees |
|---|---|---|
| McKinstry | Seattle | 1,001-5,000 |
| MacDonald-Miller Facility Solutions | Seatac | 1,001-5,000 |
| MSV International, Inc. | Kenmore | 501-1,000 |
| Parametrix | Seattle | 501-1,000 |
| Prime Electric | Bellevue | 501-1,000 |
| Cumming Corporation | Seattle | 501-1,000 |
| Apollo Mechanical Contractors | Kennewick | 501-1,000 |
| Action Ready Labor | Duvall | 501-1,000 |
| KPG | Seattle | 51-200 |
| Rb Construction | Bothell | 51-200 |
Company-level data from Ken's database, ranked by employee count. This table reads each company's state from its address, so it can include large companies the count above misses because their record stores the state with a ZIP code. Public bodies, schools, job boards and companies with 50 employees or fewer are left out.
How We Counted
In short We counted construction companies in Ken's database with headquarters in Washington on Oct 17, 2026.
- Filter: Companies in Construction and its sub-industries (contractors, civil engineering), excluding real estate, utilities and architecture firms, with headquarters in Washington, United States, and at least one employee on record.
- Headquarters only. Companies with just an office in Washington are not counted.
- These are companies in Ken's database (250M people and 24M companies), not every company that exists.
- Some records store the state with a ZIP code, and the state filter misses those, so read the count as a floor. The largest-companies table reads the state from each record's address, so it includes them.
- Counts as of Oct 17, 2026. We check them weekly, and the dates move only when a count or a listed company changes.
- Pages publish only at 50 companies or more. Ken is our product, and these counts come from its company database.
{"industries":["Construction"],"excludeIndustries":["Real Estate","Utilities","Architecture and Planning"],"countries":["US"],"states":["Washington"],"employeesCount":{"min":1},"pageSize":0}FAQ
How many construction companies are in Washington?
Ken's database lists 5,436 construction companies headquartered in Washington as of Oct 17, 2026.
Which construction companies in Washington have the most employees?
In Ken's database, McKinstry, MacDonald-Miller Facility Solutions and MSV International, Inc. have the most employees of the construction companies headquartered in Washington.
Can I get a list of construction companies in Washington?
Yes. Run the filter on this page in Ken Search. Searching is free, and a valid email costs 1 credit ($0.02).
How often is this count updated?
We check it weekly. The dates on this page move only when a count or a listed company changes, so an older date means nothing moved since.
Why does this count differ from other sources?
Sources count differently: headquarters or any office, industry labels or government codes, and how many companies they track. This page counts headquarters in Ken's database with the filter shown above.
Do This in Ken
Search these companies in Ken
Open Ken Search with the same filter to see all 5,436 companies, narrow them by size or city, and find a valid email for the people you want to reach.
- Set these filters: Industry: "Construction", excluding "Real Estate", "Utilities" and "Architecture and Planning"; HQ state: Washington; HQ country: United States; Employees on record: 1 or more.
- Narrow by employee range or city.
- Find valid emails and add the companies to a campaign.
- Module
- Ken Search
- Open in Ken
- /waitlist
- API
POST /v1/search/companies- MCP tool
search_search_companies- Cost
- Free to search, 1 credit ($0.02) per valid email
The new Ken opens to the waiting list in batches.
Related
Sources
| Source | Checked |
|---|---|
| Ken's company database, queried through Ken Search (POST /v1/search/companies) | |
| Ken pricing (credit cost per valid email) |
Changelog
- Page published with counts from Ken's database.