| Midwest | ||
| Rank | Comapnay/Location | $Million |
| 7 | FirstEnergy Facilities Services Group, Akron, Ohio | $398.00 |
| 9 | Residential Services Group, Dayton, Ohio | $350.00 |
| 12 | Roto-Rooter, Cincinnatti | $276.61 |
| 18 | MMC Corp., Leawood, Kan. | $185.90 |
| 22 | Murphy Co. Mechanical Contractors and Engineers, St. Louis | $163.30 |
| 23 | J.F. Ahern Co., Fond du Lac, Wis. | $158.96 |
| 24 | John E. Green Co., Highland Park, Mich. | $158.00 |
| 25 | Exelon Services, Qwestchester, Ill. | $155.00 |
| 26 | Hill Mechanical Group, Chicago | $154.90 |
| 29 | S.A. Comunale Co. Inc., Barberton, Ohio | $128.80 |
| Northeast | ||
| Rank | Company/Location | $Million |
| 1 | EMCOR Group Inc., Norwalk, Conn. | $1,848.00 |
| 6 | Limbach Facility Services, Pittsbrugh | $448.80 |
| 8 | PPL Energy Services Holdings LLC, Allentown, Pa. | $380.44 |
| 14 | John J. Kirlin Inc., Rockville, Md. | $223.00 |
| 16 | Sauer Inc., Pittsburgh | $188.00 |
| 34 | John W. Danforth Co., Buffalo, N.Y. | $103.60 |
| 43 | Herman Goldner Co. Inc., Philadelphia | $90.50 |
| 53 | Joseph Davis Inc., Buffalo, N.Y. | $79.50 |
| 55 | W.E. Bowers Associates Inc., Beltsville, Md. | $78.00 |
| 60 | Joule Industrial Contractors, Philadelphia | $74.50 |
| South | ||
| Rank | Company/Location | $Million |
| 2 | Comfort Systems USA Inc., Houston | $819.55 |
| 3 | American Residential Services/AMS/Rescue Rooter, Downers Grove, Ill. | $690.50 |
| 4 | Lennox Retail/Service Experts, Richardson, Texas | $611.70 |
| 13 | TDIndustries, Dallas | $248.00 |
| 36 | The Coastal Group, Melbourne, Fla. | $98.10 |
| 38 | Brandt Engineering Co. Inc., Dallas | $94.00 |
| 40 | Ivey Mechanical, Kosciusko, Miss. | $92.4 |
| 42 | VSC/Virginia Sprinkler Corp., Ashland, Va. | $91.1 |
| 45 | Stanley Jones Corp., South Fulton, Tenn. | $89.65 |
| 58 | American Plumbing and Mechanical (AMPAM), Round Rock, Texas | $76.00 |
| West | ||
| Rank | Company/Location | $Million |
| 5 | Kinetic Systems Inc., Union City, Calif. | $452.00 |
| 10 | Southland Industries, Irvine, Calif. | $342.00 |
| 11 | ACCO Engineered Systems Inc., Glendale, Calif. | $315.00 |
| 17 | Beutler Corp., McClellan Park, Calif. | $187.00 |
| 19 | Cal-Air Inc., Whittier, Calif. | $180.00 |
| 20 | Therma Inc., San Jose, Calif. | $179.40 |
| 21 | Chas Roberts Air Conditioning Inc., Phoenix | $172.80 |
| 27 | Harder Mechanical Contractors Inc., Portland, Ore. | $140.05 |
| 28 | McKinstry Co., Seattle | $136.00 |
| 31 | JH Kelly LLC, Longview, Wash. | $127.00 |