| 1 | Black & Mcdonald Group LIMITED | Canada | Toronto | 2 Bloor St E Suite 2100 | Ontario | M4W 1A8 | blackandmcdonald.***** | 2017 | $1,760,512,000 | 6,500 | N/A | N/A | N/A |
| 2 | Black & Mcdonald LIMITED | Canada | Toronto | 2100-2 Bloor St E | Ontario | M4W 1A8 | blackandmcdonald.***** | 2017 | $1,489,664,000 | 5,500 | N/A | N/A | N/A |
| 3 | The Arcticom Group Canada LTD | Canada | Burnaby | 4340 Dawson St | British Columbia | V5C 4B6 | ctcontroltemp.***** | 2024 | $622,950,400 | 2,300 | N/A | N/A | N/A |
| 4 | Reliance Comfort LIMITED Partnership | Canada | Toronto | 2 Lansing Sq | Ontario | M2J 4P8 | reliancehomecomfort.***** | 1997 | $406,272,000 | 1,500 | N/A | N/A | N/A |
| 5 | MODERN/NIAGARA Group INC | Canada | Ottawa | 10b Hearst Way | Ontario | K2L 2P4 | modernniagara.***** | 2024 | $352,102,400 | 1,300 | N/A | N/A | N/A |
| 6 | Trotter And Morton Building Technologies INC | Canada | Calgary | 5799 3 St Se | Alberta | T2H 1K1 | trotterandmorton.***** | 2024 | $338,560,000 | 1,250 | N/A | N/A | N/A |
| 7 | E.S. Fox LIMITED | Canada | Niagara Falls | 9127 Montrose Rd | Ontario | L2E 7J9 | esfox.***** | 1964 | $270,848,000 | 1,000 | N/A | N/A | N/A |
| 8 | Sunny Corner Enterprises INC | Canada | Miramichi | 259 Dalton Ave | New Brunswick | E1V 3C4 | scei.***** | 2015 | $189,593,600 | 700 | N/A | N/A | N/A |
| 9 | Modern Niagara Design Services INC | Canada | Ottawa | 85 Denzil Doyle Crt | Ontario | K2M 2G8 | modernniagara.***** | 1962 | $189,593,600 | 700 | N/A | N/A | N/A |
| 10 | Modern Niagara Building Services INC | Canada | Ottawa | 10b Hearst Way | Ontario | K2L 2P4 | modernniagara.***** | 2023 | $162,508,800 | 600 | N/A | N/A | N/A |
| 11 | 2953-6778 Quebec INC | Canada | Boucherville | 549 Rue de Verrazano | Québec | J4B 7W2 | residencessoleil.***** | 1992 | $142,195,200 | 525 | N/A | N/A | N/A |
| 12 | Tbc Constructions INC | Canada | Québec | 760 Av Godin | Québec | G1M 2K4 | tbc.***** | 2014 | $135,424,000 | 500 | N/A | N/A | N/A |
| 13 | Guthrie Investments LTD | Canada | Fort Mcmurray | 9912 Manning Ave | Alberta | T9H 2B9 | guthriemech.***** | 1994 | $135,424,000 | 500 | N/A | N/A | N/A |
| 14 | Lockerbie & Hole Contracting LIMITED | Canada | Edmonton | 14940 121a Ave Nw | Alberta | T5V 1A3 | lockerbiehole.***** | 2000 | $135,424,000 | 500 | N/A | N/A | N/A |
| 15 | Guthrie Mechanical Services LTD | Canada | Fort Mcmurray | 9912 Manning Ave | Alberta | T9H 2B9 | guthriemech.***** | 2019 | $135,424,000 | 500 | N/A | N/A | N/A |
| 16 | Minus Forty Qbd CORP | Canada | Georgetown | 30 Armstrong Ave | Ontario | L7G 4R9 | minus-40.***** | 2021 | $135,424,000 | 500 | N/A | N/A | N/A |
| 17 | Cogesmic INC | Canada | Sainte-marie | 745 Av Lasalle | Québec | G6E 1S2 | N/A | 1989 | $135,424,000 | 500 | N/A | N/A | N/A |
| 18 | Troy Life & Fire Safety LTD | Canada | Owen Sound | 1042 2nd Ave E | Ontario | N4K 2H7 | troylfs.***** | 2007 | $132,336,824 | 1,050 | N/A | N/A | N/A |
| 19 | Kel-Gor LIMITED | Canada | Sarnia | 1411 Plank Rd | Ontario | N7T 7H3 | kelgor.***** | 1969 | $121,881,600 | 450 | N/A | N/A | N/A |
| 20 | Lamsar INC | Canada | Sarnia | 608 Mcgregor Rd | Ontario | N7T 7J2 | lamsar.***** | 1979 | $108,339,200 | 400 | N/A | N/A | N/A |
| 21 | Vollmer INC | Canada | Windsor | 3822 Sandwich St | Ontario | N9C 1C1 | vollmer.***** | 1965 | $108,339,200 | 400 | N/A | N/A | N/A |
| 22 | Arpi's Industries LTD | Canada | Calgary | 6815 40 St Se | Alberta | T2C 2W7 | arpis.***** | 2004 | $98,588,672 | 364 | N/A | N/A | N/A |
| 23 | 9371-2222 Quebec INC. | Canada | Québec | 1700 Rue Leon-harmel | Québec | G1N 4R9 | groupenoel.***** | 2017 | $94,796,800 | 350 | N/A | N/A | N/A |
| 24 | Anmar Mechanical And Electrical Contractors LTD | Canada | Greater Sudbury | 199 Mumford Rd | Ontario | P3Y 0A4 | anmar.***** | 2018 | $94,796,800 | 350 | N/A | N/A | N/A |
| 25 | Gateway Mechanical Services INC | Canada | Edmonton | 14605 118 Ave Nw | Alberta | T5L 2M7 | vectorindustries.***** | 1978 | $94,796,800 | 350 | N/A | N/A | N/A |
| 26 | Lorneville Mechanical Contractors LTD | Canada | Saint John | 75 Stinson Dr | New Brunswick | E2M 7E3 | lorneville.***** | 2020 | $92,465,667 | 500 | N/A | N/A | N/A |
| 27 | Modern Niagara Vancouver INC. | Canada | North Vancouver | 200-788 Harbourside Dr | British Columbia | V7P 3R7 | keithplumbingandheatingcoltd.***** | 1959 | $89,379,840 | 330 | N/A | N/A | N/A |
| 28 | Developpement Edf Renouvelables INC | Canada | Toronto | 53 Jarvis St Suite 300 | Ontario | M5C 2H2 | edf-en.***** | 2008 | $82,337,792 | 304 | N/A | N/A | N/A |
| 29 | Brymark Installations Group INC | Canada | Port Coquitlam | 1648 Broadway St | British Columbia | V3C 2M8 | brymarkgroup.***** | 1983 | $81,254,400 | 300 | N/A | N/A | N/A |
| 30 | Lisi Mechanical Contractors LTD | Canada | Toronto | 160 Disco Rd | Ontario | M9W 1M4 | lisimechanical.***** | 1979 | $74,483,200 | 275 | N/A | N/A | N/A |
| 31 | Neelands Group LIMITED | Canada | Burlington | 4131 Palladium Way | Ontario | L7M 0V9 | neelands.***** | 1958 | $68,795,392 | 254 | N/A | N/A | N/A |
| 32 | Penguin Power Solar | Canada | Wingham | 2118 Huron Bruce Rd | Ontario | N0G 2W0 | N/A | 2008 | $67,712,000 | 250 | N/A | N/A | N/A |
| 33 | Atlantica Mechanical Contractors Incorporated | Canada | Halifax | 9 Ralston Ave | Nova Scotia | B3B 1H5 | atlanticacontractors.***** | 2016 | $67,712,000 | 250 | N/A | N/A | N/A |
| 34 | Multitech Trades CORP | Canada | Mississauga | 2-2025 Meadowvale Blvd | Ontario | L5N 5N1 | multitechcorp.***** | 1978 | $67,712,000 | 250 | N/A | N/A | N/A |
| 35 | Av-Tech INC | Canada | Québec | 2300 Rue Leon-harmel Bureau 101 | Québec | G1N 4L2 | avlog.***** | 1984 | $60,940,800 | 225 | N/A | N/A | N/A |
| 36 | Hoover Mechanical Plumbing & Heating LTD | Canada | Calgary | 1-3640 61 Ave Se | Alberta | T2C 2J3 | hoovermechanical.***** | 1998 | $60,940,800 | 225 | N/A | N/A | N/A |
| 37 | Abco Supply & Service LTD | Canada | Winnipeg | 1346 Spruce St | Manitoba | R3E 2V7 | abcosupply.***** | 1972 | $59,586,560 | 220 | N/A | N/A | N/A |
| 38 | Silfab Solar INC | Canada | Mississauga | 240 Courtneypark Dr E | Ontario | L5T 2S5 | silfabsolar.***** | 2010 | $59,586,560 | 220 | N/A | N/A | N/A |
| 39 | Arpi's North INC | Canada | Edmonton | 14445 123 Ave Nw | Alberta | T5L 2Y1 | arpisnorth.***** | 2006 | $54,982,144 | 203 | N/A | N/A | N/A |
| 40 | Pitt Meadows Plumbing & Mechanical Systems (2001) LTD | Canada | Maple Ridge | 20142 113b Ave | British Columbia | V2X 0Y9 | pittmeadows.***** | 2001 | $54,440,448 | 201 | N/A | N/A | N/A |
| 41 | Hts Engineering LTD | Canada | Toronto | 115 Norfinch Dr | Ontario | M3N 1W8 | htseng.***** | 2013 | $54,169,600 | 200 | N/A | N/A | N/A |
| 42 | Kolostat INC | Canada | Laval | 2005 Rue le Chatelier | Québec | H7L 5B3 | kolostat.***** | 2019 | $54,169,600 | 200 | N/A | N/A | N/A |
| 43 | Leprohon INC | Canada | Sherbrooke | 6171 Boul Bourque | Québec | J1N 1H2 | leprohon.***** | 1940 | $54,169,600 | 200 | N/A | N/A | N/A |
| 44 | Stuart Olson Industrial Constructors INC | Canada | Greater Sudbury | 1-670 Falconbridge Rd | Ontario | P3A 4S4 | stuartolson.***** | 2011 | $53,357,056 | 197 | N/A | N/A | N/A |
| 45 | National Energy CORPORATION | Canada | Toronto | 25 Sheppard Ave W Suite 1700 | Ontario | M2N 6S6 | nationalhomeservices.***** | 2003 | $51,461,120 | 190 | N/A | N/A | N/A |
| 46 | Master Mechanical Contractors INC | Canada | Saint John | 11 Whitebone Way | New Brunswick | E2J 4Y3 | N/A | 1995 | $50,106,880 | 185 | N/A | N/A | N/A |
| 47 | Navada Ltee | Canada | Longueuil | 675 Rue Herelle | Québec | J4G 2M8 | navada.***** | 1978 | $50,106,880 | 185 | N/A | N/A | N/A |
| 48 | S.A.T Solar & Alternative Technology | Canada | Mississauga | 28-1935 Drew Rd | Ontario | L5S 1M7 | alternativetechnology.***** | 1996 | $46,613,000 | 200 | N/A | N/A | N/A |
| 49 | Kelson Mechanical INC | Canada | Sharon | 2 Bales Dr W | Ontario | L0G 1V0 | kelson.***** | 2011 | $46,613,000 | 200 | N/A | N/A | N/A |
| 50 | Vet's Sheet Metal LTD | Canada | Edmonton | 6111 56 Ave Nw | Alberta | T6B 3E2 | vetsgroup.***** | 2005 | $46,613,000 | 200 | N/A | N/A | N/A |
| 51 | Prime Boiler Services LTD | Canada | Red Deer | 155 Queens Dr | Alberta | T4P 0R3 | primeboiler.***** | 2013 | $46,613,000 | 200 | N/A | N/A | N/A |
| 52 | Groupe Beaudoin INC | Canada | Lévis | 1170 Ch Olivier | Québec | G7A 2M7 | groupebeaudoin.***** | 2007 | $46,613,000 | 200 | N/A | N/A | N/A |
| 53 | Bmp Mechanical LTD | Canada | Calgary | 110-6420 6a St Se | Alberta | T2H 2B7 | bmpmechanical.***** | 2005 | $46,613,000 | 200 | N/A | N/A | N/A |
| 54 | Les Entreprises De Refrigeration L.S. INC. | Canada | Laval | 1610 Rue Guillet | Québec | H7L 5B2 | entreprisesls.***** | 1978 | $46,613,000 | 200 | N/A | N/A | N/A |
| 55 | University Plumbing & Heating LTD | Canada | Toronto | 3655 Keele St | Ontario | M3J 1M8 | universityplumbing.***** | 1995 | $41,951,700 | 180 | N/A | N/A | N/A |
| 56 | Ambassador Mechanical L.P. | Canada | Oak Bluff | 110-400 Fort Whyte Way | Manitoba | R4G 0B1 | ambassadormechanical.***** | 2012 | $40,627,200 | 150 | N/A | N/A | N/A |
| 57 | Canyon Plumbing & Heating LTD | Canada | Calgary | 3185 114 Ave Se | Alberta | T2Z 3X2 | canyonplumbing.***** | 1978 | $39,154,920 | 168 | N/A | N/A | N/A |
| 58 | Abco Holdings LTD | Canada | Winnipeg | 1346 Spruce St | Manitoba | R3E 2V7 | abcosupply.***** | 1997 | $35,658,945 | 153 | N/A | N/A | N/A |
| 59 | Urban Mechanical Contracting LTD | Canada | Toronto | 254 Attwell Dr | Ontario | M9W 5B2 | urbanmechanical.***** | 1993 | $34,959,750 | 150 | N/A | N/A | N/A |
| 60 | J.P. Lessard Canada INC | Canada | Montréal | 9455 Rue J.-j.-gagnier | Québec | H1Z 3C8 | jplessard.***** | 1994 | $34,959,750 | 150 | N/A | N/A | 3037321 |
| 61 | Culliton INC | Canada | Stratford | 473 Douro St | Ontario | N5A 3S9 | culliton.***** | 2005 | $34,959,750 | 150 | N/A | N/A | N/A |
| 62 | Modern Niagara Toronto INC | Canada | Ottawa | 10b Hearst Way | Ontario | K2L 2P4 | modernniagara.***** | 2021 | $34,959,750 | 150 | N/A | N/A | N/A |
| 63 | Centre De Plomberie St-Jerome INC | Canada | Mirabel | 18165 Rue J.a. Bombarbier | Québec | J7J 0E7 | orampdb.***** | 1971 | $34,959,750 | 150 | N/A | N/A | N/A |
| 64 | Coral Canada Wide LTD | Canada | Calgary | 30-2150 29 St Ne | Alberta | T1Y 7G4 | coralcanadawide.***** | 2014 | $33,328,295 | 143 | N/A | N/A | N/A |
| 65 | Applied Systems Technologies INC | Canada | Woodbridge | 6-155 Rowntree Dairy Rd | Ontario | L4L 6E1 | N/A | 2023 | $33,141,135 | 130 | N/A | N/A | N/A |
| 66 | Charlton & Hill LIMITED | Canada | Lethbridge | 2620 5 Ave N | Alberta | T1H 6J6 | charltonandhill.***** | 1941 | $32,629,100 | 140 | N/A | N/A | N/A |
| 67 | Mdf Mechanical LIMITED | Canada | Brampton | 2100 Steeles Ave E | Ontario | L6T 1A7 | mdfmechanical.***** | 1986 | $32,629,100 | 140 | N/A | N/A | N/A |
| 68 | 1458013 Ontario INC | Canada | Cambridge | 145 Sheldon Dr | Ontario | N1R 5X5 | aireonekw.***** | 2001 | $32,629,100 | 140 | N/A | N/A | N/A |
| 69 | Plomberie Daniel Cote INC | Canada | Laval | 3000 Montee Saint-aubin | Québec | H7L 3N8 | plomberie.***** | 1986 | $30,997,645 | 133 | N/A | N/A | N/A |
| 70 | East Side Ventilation LTD | Canada | Winnipeg | 11 Durand Rd | Manitoba | R2J 3T1 | eastsideventilation.***** | 1994 | $30,298,450 | 130 | N/A | N/A | N/A |
| 71 | Sterling Plumbing & Heating LTD | Canada | Regina | 1625 8th Ave | Saskatchewan | S4R 1E6 | saskenergy.***** | 2003 | $30,298,450 | 130 | N/A | N/A | N/A |
| 72 | Ventilation G.R. INC | Canada | Laval | 1645 Boul Saint-elzear O | Québec | H7L 3N6 | ventilationgr.***** | 1977 | $29,793,280 | 110 | N/A | N/A | N/A |
| 73 | Milani Plumbing Drainage & Heating LTD | Canada | Burnaby | 5526 Kingsway | British Columbia | V5H 2G2 | milani.***** | 1966 | $29,599,255 | 127 | N/A | N/A | N/A |
| 74 | Ryfan INC | Canada | Yellowknife | 9 Nahanni Dr | Northwest Territories | X1A 0E8 | nexumsystems.***** | 1979 | $29,133,125 | 125 | N/A | N/A | N/A |
| 75 | Rose Mechanical LTD | Canada | Williamstown | 17631 Headline Rd 44 | Ontario | K0C 2J0 | N/A | 1986 | $29,133,125 | 125 | N/A | N/A | N/A |
| 76 | Norweld Mechanical Installations INC | Canada | Prince George | 1416 Santa Fe Rd | British Columbia | V2N 5T5 | norweld.***** | 2006 | $29,133,125 | 125 | N/A | N/A | N/A |
| 77 | Climat-Control Sb INC | Canada | Saint-bruno-de-montarville | 1061 Rue Marie-victorin | Québec | J3V 0M7 | zero-c.***** | 1993 | $27,967,800 | 120 | N/A | N/A | N/A |
| 78 | Mapleridge Mechanical Contacting INC | Canada | Pickering | 939 Dillingham Rd | Ontario | L1W 1Z7 | mrmmech.***** | 1988 | $27,967,800 | 120 | N/A | N/A | N/A |
| 79 | Lopes LIMITED | Canada | Greater Sudbury | 84 Smelter Rd | Ontario | P0M 1M0 | lopesltd.***** | 1976 | $25,637,150 | 110 | N/A | N/A | N/A |
| 80 | Viking Installations (calgary) LTD | Canada | Calgary | 4020 4 St Se | Alberta | T2G 2W3 | vikinginstallations.***** | 1977 | $25,637,150 | 110 | N/A | N/A | N/A |
| 81 | Brazzo Contractors (calgary) LTD | Canada | Calgary | 1-2624 54 Ave Se | Alberta | T2C 1R5 | asmindustries.***** | 1999 | $25,637,150 | 110 | N/A | N/A | N/A |
| 82 | Trs Heating & Cooling LTD | Canada | Elizabethtown | 3520 Coon'S Rd | Ontario | K6T 1A6 | hallofflame.***** | 2000 | $25,637,150 | 110 | N/A | N/A | N/A |
| 83 | Lowe Mechanical Services LTD | Canada | Winnipeg | 72 Park Lane Ave | Manitoba | R2R 0K2 | lowecanada.***** | 1977 | $23,539,565 | 101 | N/A | N/A | N/A |
| 84 | Beaulieu Plumbing & Mechanical INC | Canada | Edmundston | 5 Av Rousseau | Nouveau-brunswick | E3V 4H4 | beaulieumech.***** | 1984 | $23,306,500 | 100 | N/A | N/A | N/A |
| 85 | Mott Electric General Partnership | Canada | Vancouver | 440 Hastings St W Unit 200 | British Columbia | V6B 1L1 | mottelectric.***** | N/A | $23,306,500 | 100 | N/A | N/A | N/A |
| 86 | Prairie Metal Industries INC | Canada | Edmonton | 16420 130 Ave Nw | Alberta | T5V 1J8 | weblocal.***** | 2001 | $23,306,500 | 100 | N/A | N/A | N/A |
| 87 | Sprint Mechanical INC | Canada | Toronto | 50 Woodbine Downs Blvd | Ontario | M9W 5R2 | sprintinsight.***** | 2001 | $23,306,500 | 100 | N/A | N/A | N/A |
| 88 | Msb Mechanical LTD | Canada | Newmarket | 7-1160 Kerrisdale Blvd | Ontario | L3Y 8Z9 | msbmechanical.***** | 2010 | $23,306,500 | 100 | N/A | N/A | N/A |
| 89 | R F Contracting INC | Canada | Sault Ste Marie | 116 Industrial Park Cres | Ontario | P6B 5P2 | rfcontracting.***** | 2005 | $23,306,500 | 100 | N/A | N/A | N/A |
| 90 | Southern Comfort Mechanical INC | Canada | Niverville | 369 Bronstone Dr | Manitoba | R0A 1E0 | southerncomfortmechanical.***** | 2001 | $23,306,500 | 100 | N/A | N/A | N/A |
| 91 | University Sprinkler Systems Incorporated | Canada | Delta | 500-1777 56 St | British Columbia | V4L 0A6 | universitysprinklers.***** | 1985 | $23,306,500 | 100 | N/A | N/A | N/A |
| 92 | Belisle, G. Holdings (london) LIMITED | Canada | London | 4231 Blakie Rd | Ontario | N6L 1B8 | tornadoinsulation.***** | 1977 | $23,306,500 | 100 | N/A | N/A | N/A |
| 93 | Groupe Plombaction INC | Canada | Victoriaville | 575 Boul Pierre-roux E | Québec | G6T 1S7 | groupeplombaction.***** | 1987 | $23,306,500 | 100 | N/A | N/A | N/A |
| 94 | Groupe Paquette Mecanique Du Batiment INC. | Canada | Laval | 275 Boul Marc-aurèle-fortin | Québec | H7L 2A2 | f.***** | 1956 | $23,306,500 | 100 | N/A | N/A | N/A |
| 95 | Priority Mechanical LTD | Canada | Edmonton | 9259 35 Ave Nw | Alberta | T6E 5Y1 | prioritymechanical.***** | 1990 | $23,306,500 | 100 | N/A | N/A | N/A |
| 96 | Custom Air Conditioning LTD | Canada | Port Coquitlam | 1835 Broadway St | British Columbia | V3C 4Z1 | customair.***** | 2019 | $23,306,500 | 100 | N/A | N/A | N/A |
| 97 | Canadian Structural & Mechanical LTD | Canada | Sarnia | 1399 Lougar Ave | Ontario | N7S 5N5 | cansam.***** | 2018 | $23,306,500 | 100 | N/A | N/A | N/A |
| 98 | Confort Expert INC | Canada | Montréal | 9771 Boul Metropolitain E | Québec | H1J 0A4 | confortexpert.***** | 1990 | $23,306,500 | 100 | N/A | N/A | N/A |
| 99 | L. A. Brayer Industries LTD | Canada | Edmonton | 3811 93 St Nw | Alberta | T6E 5K5 | labrayer.***** | 2005 | $23,306,500 | 100 | N/A | N/A | N/A |
| 100 | Gisborne Fire Protection Alberta LTD | Canada | Burnaby | 7476 Hedley Ave | British Columbia | V5E 2P9 | gisborne.***** | 1985 | $23,306,500 | 100 | N/A | N/A | N/A |