| 1 | Mitie Fm LIMITED | Unitedkingdom | Rotherhithe | The Shard, Level 12 | London | SE1 9SG | mitie.***** | 1887 | $1,397,342,911 | 9,457 | N/A | N/A | N/A |
| 2 | Ocs UK&I LIMITED | Unitedkingdom | Ipswich | New Century House | Suffolk | IP3 9SJ | N/A | 2007 | $1,049,248,983 | 27,797 | N/A | N/A | N/A |
| 3 | Mitie LIMITED | Unitedkingdom | Rotherhithe | Level 12, the Shard | London | SE1 9SG | mitie.***** | 1994 | $979,768,832 | 1,023 | N/A | N/A | N/A |
| 4 | Equans Services LIMITED | Unitedkingdom | North Brunton | Neon | Newcastle Upon Tyne, Tyne and Wear | NE12 8BU | engie.***** | 1858 | $947,825,548 | 6,713 | N/A | N/A | N/A |
| 5 | Iss Facility Services LIMITED | Unitedkingdom | Weybridge | Velocity | Surrey | KT13 0SL | uk.***** | 1966 | $864,539,780 | 11,849 | N/A | N/A | N/A |
| 6 | Ocs Group UK LIMITED | Unitedkingdom | Ipswich | New Century House | Suffolk | IP3 9SJ | ansaback.***** | 1995 | $714,528,835 | 16,696 | N/A | N/A | N/A |
| 7 | Bidvest Noonan (UK) LIMITED | Unitedkingdom | Moorgate | Beaufort House | London | EC3A 7BB | bidvestnoonan.***** | 1998 | $635,836,370 | 16,581 | N/A | N/A | N/A |
| 8 | Iss Mediclean LIMITED | Unitedkingdom | Weybridge | Velocity 1 | Surrey | KT13 0SL | uk.***** | 1982 | $593,083,687 | 12,023 | N/A | N/A | N/A |
| 9 | Mitie Cleaning & Environmental Services LIMITED | Unitedkingdom | Rotherhithe | The Shard, Level 12 | London | SE1 9SG | mitie.***** | 1961 | $528,976,247 | 13,585 | N/A | N/A | N/A |
| 10 | Churchill Contract Services Group Holdings LIMITED | Unitedkingdom | Luton | First Floor, Cedar House | Luton | LU1 3LU | churchillservices.***** | 2010 | $486,212,616 | 14,811 | N/A | N/A | N/A |
| 11 | Kingspan LIMITED | Unitedkingdom | Holywell | 2-4 Greenfield Business Park 2 Bagillt Road | Flintshire | CH8 7GJ | kingspanpanels.***** | 1972 | $452,200,556 | 935 | N/A | N/A | N/A |
| 12 | Equans E&S Solutions LIMITED | Unitedkingdom | Herne Hill | Becket House | London | SE1 7EU | bouygues-uk.***** | 1929 | $451,336,626 | 1,858 | N/A | N/A | N/A |
| 13 | Emcor Group (UK) PLC | Unitedkingdom | Surbiton | 1 the Crescent | London | KT6 4BN | emcoruk.***** | 1964 | $422,112,752 | 3,009 | N/A | N/A | N/A |
| 14 | Telehouse Holdings LIMITED | Unitedkingdom | Stepney | Telehouse | London | E14 2AA | telehouse.***** | 1993 | $398,890,471 | 366 | N/A | N/A | N/A |
| 15 | Churchill Contract Services LIMITED | Unitedkingdom | Luton | Cedar House | Luton | LU1 3LU | churchillservices.***** | 1999 | $348,900,635 | 12,091 | N/A | N/A | N/A |
| 16 | Mitie (defence) LIMITED | Unitedkingdom | Rotherhithe | Level 12 the Shard | London | SE1 9SG | mitie.***** | 1991 | $325,589,429 | 1,446 | N/A | N/A | N/A |
| 17 | Personnel Hygiene Services LIMITED | Unitedkingdom | Caerphilly | Block B | Caerphilly | CF83 1XH | phs.***** | 1963 | $306,782,013 | 2,222 | N/A | N/A | N/A |
| 18 | Kier Facilities Services LIMITED | Unitedkingdom | Cadishead | 2nd Floor Optimum House | Manchester, Greater Manchester | M50 3XP | kier.***** | 1991 | $299,776,284 | 936 | N/A | N/A | N/A |
| 19 | Dalkia Engineering LIMITED | Unitedkingdom | Thorneywood | Level 2 2nd Floor Lock House | Nottingham | NG2 1AG | N/A | 1913 | $288,808,384 | 744 | N/A | N/A | N/A |
| 20 | Abm Facility Services UK LIMITED | Unitedkingdom | Ruislip | Artemis | London | HA4 6QE | abm.***** | 1987 | $272,426,142 | 5,329 | N/A | N/A | N/A |
| 21 | Landmarc Support Services LIMITED | Unitedkingdom | London | 12 Level | London | SE1 9SG | N/A | 2003 | $258,779,348 | 1,304 | N/A | N/A | N/A |
| 22 | Kingdom Services Group LIMITED | Unitedkingdom | Newton-le-willows | Willow House | Saint Helens, Merseyside | WA12 0HF | kingdom.***** | 1993 | $241,168,680 | 6,372 | N/A | N/A | N/A |
| 23 | Kch Interventional Facilities Management Llp | Unitedkingdom | Herne Hill | Unit 1 Industrial Estate | London | SE5 9NY | kings-fm.***** | 2016 | $239,724,915 | 359 | N/A | N/A | N/A |
| 24 | Gov Facility Services LIMITED | Unitedkingdom | London | 1st Floor, Albany House | London | SW1H 9EA | gov.***** | 2017 | $204,307,834 | 1,607 | N/A | N/A | N/A |
| 25 | 2gether Support Solutions LIMITED | Unitedkingdom | Canterbury | Room 07.g.023 Trust Man. | Kent | CT1 3NG | 2gethersupportsolutions.***** | 2018 | $202,881,354 | 1,469 | N/A | N/A | N/A |
| 26 | Robertson Facilities Management LIMITED | Unitedkingdom | Elgin | 10 Perimeter Road | Moray | IV30 6AE | robertson.***** | 1986 | $202,792,270 | 1,543 | N/A | N/A | N/A |
| 27 | Nic Services Group LIMITED | Unitedkingdom | Collingham | Hoyland House | Leeds, West Yorkshire | LS12 2HG | nicgroup.***** | 2004 | $202,114,199 | 7,655 | N/A | N/A | N/A |
| 28 | Amey Defence Services LIMITED | Unitedkingdom | Huntingdon | Swales Pavilion Raf Wyton | Cambridgeshire | PE28 2EA | N/A | 2005 | $198,419,988 | 1,147 | N/A | N/A | N/A |
| 29 | City Building (glasgow) Llp | Unitedkingdom | Drumchapel | 350 Darnick Street | Glasgow City | G21 4BA | citybuildingglasgow.***** | 2006 | $195,723,568 | 1,668 | N/A | N/A | N/A |
| 30 | City Facilities Management LIMITED | Unitedkingdom | Drumchapel | Caledonia House | Glasgow City | G5 0US | city-holdings.***** | 1997 | $191,264,719 | 958 | N/A | N/A | N/A |
| 31 | Cbre Holdings LIMITED | Unitedkingdom | Marylebone | Henrietta House | London | W1G 0NB | cbre.***** | 2013 | $179,641,127 | 16 | N/A | N/A | N/A |
| 32 | Mitie Pfi LIMITED | Unitedkingdom | Rotherhithe | Level 12, the Shard | London | SE1 9SG | mitie.***** | 2000 | $167,782,550 | 1,392 | N/A | N/A | N/A |
| 33 | Aramark Defence Services LIMITED | Unitedkingdom | Saint Johns Wood | The Lighthouse | London | N1 9NW | N/A | 2017 | $165,510,016 | 3,299 | N/A | N/A | N/A |
| 34 | Kbr (aspire Services Ventures) LIMITED | Unitedkingdom | Leatherhead | Hill Park Court | Surrey | KT22 7NL | kbr.***** | 2018 | $161,223,797 | 647 | N/A | N/A | N/A |
| 35 | The Coventry And Rugby Hospital Company PLC | Unitedkingdom | Swanley | Unit 8 | Kent | BR8 7AG | N/A | 2002 | $160,539,248 | 724 | N/A | N/A | N/A |
| 36 | Bam Fm LIMITED | Unitedkingdom | Drumchapel | Kelvin House | Glasgow City | G33 6FB | bam.***** | 1998 | $155,088,216 | 793 | N/A | N/A | N/A |
| 37 | York Teaching Hospital Facilities Management Llp | Unitedkingdom | Nether Poppleton | Wigginton Road | York | YO31 8HE | nhs.***** | 2018 | $143,481,882 | 802 | N/A | N/A | N/A |
| 38 | Hospital Hygiene Services LIMITED | Unitedkingdom | Rubery | 24 Parklands | Birmingham, West Midlands | B45 9PZ | N/A | 1981 | $137,189,360 | 2,721 | N/A | N/A | N/A |
| 39 | Alliance Leisure Services LIMITED | Unitedkingdom | Bristol | 2430-2440 the Quadrant | City of Bristol | BS32 4AQ | allianceleisure.***** | 1992 | $137,168,690 | 44 | N/A | N/A | N/A |
| 40 | Mitie Shared Services LIMITED | Unitedkingdom | Rotherhithe | The Shard, Level 12 | London | SE1 9SG | mitie.***** | 1987 | $136,552,601 | 500 | N/A | N/A | N/A |
| 41 | Flowtech Fluidpower PLC | Unitedkingdom | Wilmslow | Bollin House | Cheshire East | SK9 1DP | flowtechfluidpower.***** | 2014 | $135,999,460 | 596 | N/A | N/A | N/A |
| 42 | Calderdale And Huddersfield Solutions LTD | Unitedkingdom | Salendine Nook | Huddersfield Royal Infirmary | Kirklees, West Yorkshire | HD3 3EA | chs-limited.***** | 2018 | $135,970,708 | 377 | N/A | N/A | N/A |
| 43 | Kbs Maritime LIMITED | Unitedkingdom | Portsmouth | Victory Building | Portsmouth | PO1 3LS | N/A | 2021 | $133,462,829 | 357 | N/A | N/A | N/A |
| 44 | Graham Asset Management LIMITED | Unitedkingdom | Glenariffe | 20 Wildflower Way | Belfast | BT12 6TA | graham.***** | 2008 | $129,421,880 | 688 | N/A | N/A | N/A |
| 45 | City Facilities Management (UK) LIMITED | Unitedkingdom | Drumchapel | Caledonia House | Glasgow City | G5 0US | city-holdings.***** | 1985 | $128,451,886 | 1,197 | N/A | N/A | N/A |
| 46 | Capital Hospitals (holdings) LTD. | Unitedkingdom | Swanley | 8 White Oak Square, London Road | Kent | BR8 7AG | N/A | 2005 | $126,988,777 | 624 | N/A | N/A | N/A |
| 47 | Capital Hospitals LTD. | Unitedkingdom | Swanley | 8 White Oak Square, London Road | Kent | BR8 7AG | N/A | 2005 | $126,988,777 | 603 | N/A | N/A | N/A |
| 48 | Intu Retail Services LIMITED | Unitedkingdom | Moorgate | 10 Fleet Place | London | EC4M 7RB | intugroup.***** | 2013 | $123,054,621 | 1,932 | N/A | N/A | N/A |
| 49 | Principle Cleaning Services LIMITED | Unitedkingdom | North Woolwich | Solar House | London | E15 4LJ | principlecleaning.***** | 1989 | $118,665,365 | 2,602 | N/A | N/A | N/A |
| 50 | Mdm Cleaning Zone LTD | Unitedkingdom | Boston | Flat 24 | Lincolnshire | PE21 9EH | N/A | 2023 | $117,728,438 | 25 | N/A | N/A | N/A |
| 51 | Regent Office Care LIMITED | Unitedkingdom | Aldermans Green | Unit 2 Oak Court | Coventry, West Midlands | CV6 4QH | regentsamsic.***** | 1986 | $115,248,873 | 3,786 | N/A | N/A | N/A |
| 52 | John F Hunt LIMITED | Unitedkingdom | South Stifford | Europa Park | Thurrock | RM20 4DB | johnfhunt.***** | 1981 | $113,212,549 | 436 | N/A | N/A | N/A |
| 53 | Leadec LIMITED | Unitedkingdom | Aldermans Green | Leadec Ltd | Coventry, West Midlands | CV4 9AP | leadec-services.***** | 1997 | $109,651,958 | 1,551 | N/A | N/A | N/A |
| 54 | Atlas Fm LIMITED | Unitedkingdom | Datchet | Riding Court House | Windsor and Maidenhead | SL3 9JT | atlascleaning.***** | 1991 | $109,612,753 | 630 | N/A | N/A | N/A |
| 55 | Nexgen Holdings 1 LIMITED | Unitedkingdom | West Byfleet | 4a Wintersells Road & 4b | Surrey | KT14 7LF | justaskservices.***** | 2017 | $108,716,213 | 2,856 | N/A | N/A | N/A |
| 56 | Atlas Cleaning Datchet LIMITED | Unitedkingdom | Datchet | Riding Court House | Windsor and Maidenhead | SL3 9JT | atlascleaning.***** | 1986 | $106,445,549 | 7,366 | N/A | N/A | N/A |
| 57 | Apleona UK LIMITED | Unitedkingdom | Finsbury | Ground Floor Cowcross Studios | London | EC1M 6DQ | N/A | 1996 | $106,250,709 | 1,143 | N/A | N/A | N/A |
| 58 | Mitie Cleaning (south East) LIMITED | Unitedkingdom | Docklands | 1 Lanark Square | London | E14 9RE | mitie.***** | 1987 | $102,400,437 | 2,031 | N/A | N/A | N/A |
| 59 | Uhs Estates LIMITED | Unitedkingdom | Upper Shirley | Trust Man. | Southampton | SO16 6YD | N/A | 2016 | $98,900,551 | 49 | N/A | N/A | N/A |
| 60 | Sbfm LIMITED | Unitedkingdom | Pendas Fields | 3355 Century Way Thorpe Park | Leeds, West Yorkshire | LS15 8ZB | sb-fm.***** | 2013 | $98,830,284 | 5,055 | N/A | N/A | N/A |
| 61 | Sylvamo UK LIMITED | Unitedkingdom | Aberdeen | C/o Johnston Carmichael | Aberdeen City | AB10 1YL | N/A | 1850 | $96,992,586 | 490 | N/A | N/A | N/A |
| 62 | Derby Healthcare (holdings) LIMITED | Unitedkingdom | Swanley | 8 White Oak Square, London Road | Kent | BR8 7AG | N/A | 2003 | $95,778,446 | 509 | N/A | N/A | N/A |
| 63 | Qe Facilities LIMITED | Unitedkingdom | Gateshead | Estates Department | Gateshead, Tyne and Wear | NE9 6SX | qefacilities.***** | 2014 | $93,792,379 | 804 | N/A | N/A | N/A |
| 64 | Andron Contract Services LIMITED | Unitedkingdom | Clinterty | Unit 2, Andron House | Aberdeen City | AB21 0GP | andron.***** | 1980 | $89,977,228 | 2,260 | N/A | N/A | N/A |
| 65 | G.S. Associates (scotland) LIMITED | Unitedkingdom | Renfrew | Babcock Park | Renfrewshire | PA4 8DJ | gs-associates.***** | 1997 | $86,309,662 | 3,142 | N/A | N/A | N/A |
| 66 | Incentive Facilities Management LIMITED | Unitedkingdom | Ipswich | New Century House | Suffolk | IP3 9SJ | incentive-fmgroup.***** | 2001 | $85,067,942 | 1,536 | N/A | N/A | N/A |
| 67 | Caledonian Heritable LIMITED | Unitedkingdom | Gorgie | 46 Charlotte Square | City of Edinburgh | EH2 4HQ | caledonianheritable.***** | 1981 | $84,041,835 | 1,002 | N/A | N/A | N/A |
| 68 | Highland Industrial Supplies LIMITED | Unitedkingdom | Wick Airport | 36 Seafield Road | Highland | IV1 1SG | hisltd.***** | 1984 | $82,898,625 | 545 | N/A | N/A | N/A |
| 69 | Mps Housing LIMITED | Unitedkingdom | Great Witcombe | Unit 5220 2nd Floor Valiant Court | Gloucestershire | GL3 4FE | N/A | 2018 | $82,495,674 | 620 | N/A | N/A | N/A |
| 70 | Tc Facilities Management LIMITED | Unitedkingdom | The Hermitage | Sapphire House | Surrey | KT20 7RU | tcfm.***** | 1990 | $82,462,749 | 2,660 | N/A | N/A | N/A |
| 71 | Norse Eastern LIMITED | Unitedkingdom | Swannington | 280 Fifers Lane | Norfolk | NR6 6EQ | ncsgrp.***** | 2010 | $81,801,011 | 1,114 | N/A | N/A | N/A |
| 72 | Enable Communities Group LIMITED | Unitedkingdom | Motherwell | Inspire House | North Lanarkshire | ML1 4UF | enable.***** | 2019 | $80,137,946 | 2,037 | N/A | N/A | N/A |
| 73 | Oxford Direct Services LIMITED | Unitedkingdom | Marston | Marsh Road Cowley Marsh | Oxfordshire | OX4 2HH | oxforddirectservices.***** | 2017 | $77,535,268 | 544 | N/A | N/A | N/A |
| 74 | Vebego Services B.V. | Unitedkingdom | Romford | 37-39 Manor Rd | London | RM1 2TL | vebego.***** | 1995 | $74,752,402 | 1,500 | N/A | N/A | N/A |
| 75 | Ntw Solutions LIMITED | Unitedkingdom | Coxlodge | Arran House | Newcastle Upon Tyne, Tyne and Wear | NE3 3XT | ntwsolutions.***** | 2017 | $74,144,003 | 669 | N/A | N/A | N/A |
| 76 | Cateringcleaning Facilities | Unitedkingdom | Swansea | Room 2 3 21, Civic Centre | Swansea | SA1 3SN | N/A | 2011 | $71,047,743 | 1,500 | N/A | N/A | N/A |
| 77 | Spectrum Facilities Maintenance LIMITED | Unitedkingdom | Benchill | 56 A Tib Street | Manchester, Greater Manchester | M4 1LG | N/A | 2010 | $70,838,313 | 1,405 | N/A | N/A | N/A |
| 78 | Robert Scott & Sons LIMITED | Unitedkingdom | Greenfield | Oak View Mills | Manchester, Greater Manchester | OL3 7HG | robert-scott.***** | 1925 | $70,634,118 | 366 | N/A | N/A | N/A |
| 79 | Rydon Maintenance LIMITED | Unitedkingdom | Danehill | Luxford Place | East Sussex | RH18 5HE | rydon.***** | 1981 | $70,525,540 | 734 | N/A | N/A | N/A |
| 80 | Fullfield LIMITED | Unitedkingdom | Laindon | 25 Hornsby Square Southfields Industrial Estate | Essex | SS15 6SD | fullfieldfm.***** | 2008 | $69,476,550 | 427 | N/A | N/A | N/A |
| 81 | D3s Enterprise LTD | Unitedkingdom | Wetherby | Unit 5 Cromwell Business Park | Leeds, West Yorkshire | LS22 7SU | N/A | 2018 | $68,886,688 | 2,113 | N/A | N/A | N/A |
| 82 | Abm Technical Solutions LIMITED | Unitedkingdom | Eastcote and East Ruislip | 3 Newall Road World Business Centre | London | TW6 2TA | abm.***** | 2000 | $68,617,974 | 758 | N/A | N/A | N/A |
| 83 | Norse Commercial Services LIMITED | Unitedkingdom | Swannington | 280 Fifers Lane | Norfolk | NR6 6EQ | ncsgrp.***** | 1994 | $67,435,408 | 1,204 | N/A | N/A | N/A |
| 84 | Kingdom Cleaning LIMITED | Unitedkingdom | Cadishead | 186 Moorside Road | Manchester, Greater Manchester | M27 9LE | facilicom.***** | 1987 | $67,419,537 | 2,337 | N/A | N/A | N/A |
| 85 | Integrated Facilities Management Bolton LIMITED | Unitedkingdom | Smithills | Royal Bolton Hospital | Manchester, Greater Manchester | BL4 0JR | N/A | 2016 | $67,394,871 | 703 | N/A | N/A | N/A |
| 86 | Abb Power T&D LIMITED | Unitedkingdom | Stone | Stonefield Works | Staffordshire | ST15 0RS | abb.***** | 1936 | $65,695,603 | 1,303 | N/A | N/A | N/A |
| 87 | Combined Facilities Management LTD | Unitedkingdom | Magherafelt | 65 Deerpark Road | Mid Ulster | BT45 8BS | cfm-ni.***** | 1977 | $65,447,279 | 336 | N/A | N/A | N/A |
| 88 | Galliford Try Facilities Management LIMITED | Unitedkingdom | Uxbridge | Blake House | London | UB8 2AD | gallifordtry.***** | 2019 | $61,735,366 | 134 | N/A | N/A | N/A |
| 89 | Total Support Services LIMITED | Unitedkingdom | Croydon | Unit 20, Io Centre | London | CR0 4WQ | tss-uk.***** | 1993 | $61,624,492 | 2,475 | N/A | N/A | N/A |
| 90 | Cloudfm Group LIMITED | Unitedkingdom | Highwoods | Cloudfm House | Essex | CO4 9YA | cloudfmgroup.***** | 2014 | $60,091,295 | 151 | N/A | N/A | N/A |
| 91 | Cloudfm Integrated Services LIMITED | Unitedkingdom | Highwoods | Oyster House Severalls Lane | Essex | CO4 9PD | N/A | 2010 | $59,019,304 | 139 | N/A | N/A | N/A |
| 92 | Atlas Facilities Management LIMITED | Unitedkingdom | Datchet | Riding Court House | Windsor and Maidenhead | SL3 9JT | atlasfm.***** | 2005 | $58,327,801 | 3 | N/A | N/A | N/A |
| 93 | The Carroll Cleaning Company LIMITED | Unitedkingdom | Holywell Green | Spring Hey Mill, 1 North Street | Calderdale, West Yorkshire | HX4 8DQ | carrollcleaningcompany.***** | 1987 | $58,082,375 | 1,152 | N/A | N/A | N/A |
| 94 | Micronclean LIMITED | Unitedkingdom | Skegness | Roman Bank | Lincolnshire | PE25 1SQ | micronclean.***** | 1921 | $57,299,733 | 492 | N/A | N/A | N/A |
| 95 | Slh Swansea LIMITED | Unitedkingdom | Swansea | Axis Court | Swansea | SA7 0AJ | soloservicegroup.***** | 2000 | $57,278,196 | 3,101 | N/A | N/A | N/A |
| 96 | Dalkia Facilities Northern UK LIMITED | Unitedkingdom | Timperley | 1 Old Park Lane | Manchester, Greater Manchester | M41 7HA | spie.***** | 2006 | $57,077,382 | 807 | N/A | N/A | N/A |
| 97 | Emcor UK | Unitedkingdom | Brough | Building 61 | East Riding of Yorkshire | HU15 1EQ | emcoruk.***** | 2015 | $56,621,130 | 1,200 | N/A | N/A | N/A |
| 98 | Mountjoy LTD | Unitedkingdom | Buckland | Fairfield House | Portsmouth | PO2 8AA | mountjoy.***** | 1993 | $56,287,645 | 333 | N/A | N/A | N/A |
| 99 | Solo Service Group LIMITED | Unitedkingdom | Swansea | Axis 1 | Swansea | SA7 0AJ | soloservicegroup.***** | 1989 | $55,451,241 | 3,074 | N/A | N/A | N/A |
| 100 | Pareto Facilities Management LIMITED | Unitedkingdom | Chipping Norton | Unit 5 | Oxfordshire | OX7 3PQ | pareto-fm.***** | 2014 | $52,225,329 | 637 | N/A | N/A | N/A |