Construction Companies in Maryland: 82 Verified Firms
Secwyn has verified 82 construction companies based in Maryland. The largest groups are Plumbing, Heating, and Air-Conditioning Contractors (18); Poured Concrete Foundation and Structure Contractors (10); and Commercial and Institutional Building Construction (9). By headcount, 79% have 51–200 employees, 17% have 201–500 employees, and 4% fall in other size bands. Baltimore has the most (10), followed by Rockville (4) and Beltsville (3).
Company size
- 51–200 employees65 · 79%
- 201–500 employees14 · 17%
- 501–1,000 employees3 · 4%
Top cities
- Baltimore10 · 12%
- Rockville4 · 5%
- Beltsville3 · 4%
- Frederick3 · 4%
- Gaithersburg3 · 4%
- Hanover3 · 4%
- Laurel3 · 4%
- Owings Mills3 · 4%
- Silver Spring3 · 4%
Cities with fewer than 3 companies are not listed.
Largest sub-industries
| Sub-industry | NAICS | Companies |
|---|---|---|
| Plumbing, Heating, and Air-Conditioning Contractors | 238220 | 18 |
| Poured Concrete Foundation and Structure Contractors | 238110 | 10 |
| Commercial and Institutional Building Construction | 236220 | 9 |
| Electrical Contractors and Other Wiring Installation Contractors | 238210 | 8 |
| Site Preparation Contractors | 238910 | 8 |
| Roofing Contractors | 238160 | 7 |
| Residential Remodelers | 236118 | 4 |
| All Other Specialty Trade Contractors | 238990 | 2 |
A sample of these companies
A few of the 82 construction companies in Maryland. Names, websites and contacts are shown after you sign up.
Company #1 · name shown after sign-up
Site Preparation Contractors · 51–200 employees
Company #2 · name shown after sign-up
New Single-Family Housing Construction (except For-Sale Builders) · 51–200 employees
Company #3 · name shown after sign-up
Roofing Contractors · 51–200 employees · Baltimore
Company #4 · name shown after sign-up
Plumbing, Heating, and Air-Conditioning Contractors · 51–200 employees · Baltimore
Company #5 · name shown after sign-up
Other Foundation, Structure, and Building Exterior Contractors · 51–200 employees · Hanover
Company #6 · name shown after sign-up
Commercial and Institutional Building Construction · 51–200 employees
Find the Maryland construction companies that fit what you sell
Describe what you sell and Secwyn shows the companies most likely to buy it, with the reasons for each match. Sign up free and your first 3 company reveals are on us: name, website, description with its source, contact channels and the roles to contact.
How Secwyn verifies these companies
- Every company description is a sentence visible on the company's own website. Inside the product, each one links to its source page.
- Each company has a NAICS industry code, the US government standard for classifying businesses.
- All companies are based in the United States. Location and size come from public sources, including company filings and People Data Labs.
Data updated October 6, 2026.