Contractors active in Maryland county permit records, grouped from public filings. Counts reflect permits attributed to each firm. Not every filing names a contractor, so counts here are a floor. A firm's actual permit activity is usually higher.
| Contractor | Trade | Counties | Permits | Last active |
|---|---|---|---|---|
| AT YOUR SERVICE REPAIR, INC. | Plumbing | Frederick County, Howard County | 116 | Jul 2026 |
| BRYANT GROUP, INC. | Plumbing | Frederick County | 75 | Jul 2026 |
| MEGA PLUMBING CORP | Plumbing | Frederick County, Howard County | 54 | Jul 2026 |
| CULLIGAN WATER TREATMENT | Plumbing | Frederick County | 34 | Jul 2026 |
| ROBERT A TULL INC | Plumbing | Frederick County | 28 | Jul 2026 |
| CHEASAPEAKE PLUMBING & HEATING | Plumbing | Frederick County | 26 | Jun 2026 |
| BEN LEWIS INC | Plumbing | Frederick County | 21 | Jul 2026 |
| J. A. SMITH & CO. INC. | Plumbing | Frederick County, Howard County | 19 | Jul 2026 |
| ALL AROUND PLUMBING INC | Plumbing | Frederick County | 16 | Jul 2026 |
| Nathan Burner | Plumbing | Frederick County | 14 | Jul 2026 |
| TNT PLUMBING & DRAIN SERVICE, LLC | Plumbing | Frederick County, Howard County | 14 | Jul 2026 |
| PJ Fitzpatrick LLC | Plumbing | Frederick County | 11 | Jul 2026 |
| RENOVATION EXPERTS INC | Plumbing | Frederick County | 11 | Jun 2026 |
| BRUCE BOYD | Plumbing | Frederick County | 10 | Jul 2026 |
| CLARKSBURG PLUMBING | Plumbing | Frederick County | 9 | Jul 2026 |
| Reed and Son Services, LLC | Plumbing | Frederick County | 9 | Jul 2026 |
| CASTAWAY PLUMBING | Plumbing | Frederick County, Howard County | 8 | Jun 2026 |
| Eagle Plumbing | Plumbing | Frederick County | 8 | Jul 2026 |
| MARK L MCLAUGHLIN | Plumbing | Frederick County | 8 | Jul 2026 |
| MICKS PLUMBING & HEATING | Plumbing | Frederick County | 7 | Jun 2026 |
| T BRADLEY ROHRER | Plumbing | Frederick County | 7 | Jul 2026 |
| WILLIAMS PLUMBING, LLC | Plumbing | Frederick County | 7 | Jul 2026 |
| AA ROOTER LLC DBA ROOTERMAN | Plumbing | Frederick County, Howard County | 5 | Jul 2026 |
| C.E.Rensberger & Family Builder LLC | Plumbing | Frederick County | 5 | Apr 2026 |
| DAVID L KLIPP | Plumbing | Frederick County | 5 | Jun 2026 |
| Dorcus Construction Company Inc. | Plumbing | Frederick County | 5 | Jul 2026 |
| GLADHILL PLUMBING & HTG | Plumbing | Frederick County | 5 | Jul 2026 |
| KAYWELL CONSTRUCTION CORPORATION | Plumbing | Frederick County | 5 | Jun 2026 |
| AC&T | Plumbing | Frederick County | 4 | Jul 2026 |
| Contracting LLC Stephen Lewis Barrett | Plumbing | Frederick County | 4 | Jul 2026 |
| FREDERICK PLUMBING & HEATING | Plumbing | Frederick County | 4 | May 2026 |
| Hatfield's Equipment | Plumbing | Frederick County | 4 | May 2026 |
| Ivan Reid | Plumbing | Frederick County | 4 | Jul 2026 |
| JAMES E MORGAN | Plumbing | Frederick County | 4 | Jul 2026 |
| JR ROBERT L HALLEY | Plumbing | Frederick County | 4 | Jul 2026 |
| KINSLEY CONSTRUCTION LLC | Plumbing | Frederick County, Howard County | 4 | Jun 2026 |
| Kline's Plumbing, LLC | Plumbing | Frederick County | 4 | Jun 2026 |
| Mallick Mechanical Contractors | Plumbing | Frederick County, Howard County | 4 | Jun 2026 |
| MOXLEY PLUMBING | Plumbing | Frederick County | 4 | Jun 2026 |
| SUPERIOR MECHANICAL SERVICES | Plumbing | Frederick County, Howard County | 4 | Apr 2026 |
| Bayshore Construction Services, LLC | Plumbing | Frederick County | 3 | Jun 2026 |
| BROWNS PLUMBING & HEATING, INC | Plumbing | Frederick County | 3 | Jul 2026 |
| B.T. Plumbing inc. | Plumbing | Frederick County | 3 | Jul 2026 |
| Corey's Construction | Plumbing | Frederick County | 3 | May 2026 |
| Dead Rock Contractor Services | Plumbing | Frederick County | 3 | Jun 2026 |
| Easterday-Wilson Water Services, LLC | Plumbing | Frederick County | 3 | Jun 2026 |
| Elite 4 Roofing & Remodeling,LLC | Plumbing | Frederick County | 3 | Jul 2026 |
| Holtzman Propane, LC | Plumbing | Frederick County | 3 | Jun 2026 |
| Josh Ramsburg | Plumbing | Frederick County | 3 | Jul 2026 |
| PAVEL ABAEV | Plumbing | Frederick County, Howard County | 3 | Jul 2026 |
Source: county permit records. Updated monthly.