| KPMG | London, Birmingham, Tower Hamlets | 163 | 102 |
| KPMG Audit | Tower Hamlets | 7 | 10 |
| Civil Service KPMG | Tower Hamlets | 2 | 2 |
| KPMG in India KPMG Advisory Services | Haryana | 1 | 4 |
| Civil Service Learning KPMG | Tower Hamlets | 1 | 1 |
| CSL KPMG | Tower Hamlets | 1 | 1 |
| KPMG Igh | Canary Wharf | 1 | 1 |
| KPMG LLP Lots 1 2 3 & 4 | Manchester | 1 | 1 |
| KPMG LLT | Greater London | 1 | 1 |
| KPMG Registered | | 1 | 1 |
| Ernst & Young | London, Southwark, More London Place London | 24 | 89 |
| Deloitte | London | 20 | 122 |
| Grant Thornton | London, Islington | 19 | 38 |
| Pricewaterhousecoopers | London | 14 | 75 |
| Jacobs | London, Bristol, Wokingham | 9 | 62 |
| Mott Macdonald | Croydon, Cambridge, Altincham | 7 | 60 |
| Mazars | London | 9 | 27 |
| AECOM | St Albans, London, Birmingham | 5 | 137 |
| PA Consulting Services | London | 7 | 54 |
| Fti Consulting | London | 7 | 7 |
| BDO | London | 6 | 32 |
| Steer Davies & Gleave | London | 6 | 28 |
| Arcadis Consulting | London | 6 | 23 |
| Atkins | Epsom, London, Epspm | 5 | 128 |
| Ove Arup & Partners | London | 5 | 72 |
| Systra | Woking, London, Manchester | 4 | 13 |
| Crowe | London, Ludgate Hill London | 7 | 10 |
| Costain | Maidenhead, Manchester, London | 6 | 14 |
| Santa FE Relocation Services | London, Park Royal London | 6 | 6 |
| WSP | London, Birmingham | 5 | 132 |
| Economic Consulting Associates | London | 5 | 4 |
| First Economics | East Hagbourne, London | 5 | 5 |
| Tiaa | Fareham | 4 | 14 |
| Sweco | Leeds, London | 4 | 5 |
| FRP Advisory Trading | London | 4 | 2 |
| CPC Project Services | London | 3 | 16 |
| Epiq Systems | London | 3 | 5 |
| Wylie & Bisset | Glasgow | 3 | 2 |
| Altlaw Litigation Support | London | 3 | 3 |
| Anexsys | London | 3 | 3 |
| Inventus Solutions | London | 3 | 3 |
| Legastat | London | 3 | 3 |
| Cmy Consultants | Bromley, London | 6 | 6 |
| SLG Economics | Finchley, London | 6 | 6 |
| Savills | London | 5 | 30 |
| Frontier Economics | London | 5 | 18 |
| Complete Strategy | London | 5 | 5 |
| Nera | London | 5 | 5 |
| Cepa | London | 4 | 5 |
| Anderson Anderson Brown LLP & Fragomen | Aberdeen | 4 | 4 |
| European Economic Research | London | 4 | 4 |
| Turner & Townsend | Birmingham, Manchester | 3 | 39 |
| Moorhouse Consulting | London | 3 | 13 |
| Pricewaterhouse Coopers | London, Embankment Place London | 3 | 5 |
| Gutteridge Haskins & Davey | Chester, London | 3 | 2 |
| Icon Relocation | Crowborough, Wealden | 3 | 3 |
| Smith Stone Walters | Bromley, London Road Bromley | 3 | 3 |
| Tthcurzon Relocation | Dorset, Bournemouth | 3 | 3 |
| Arcadis | Manchester, Belfast | 2 | 79 |
| Mace | London, Manchester | 2 | 26 |
| Turner & Townsend Project Management | Leeds | 2 | 13 |
| Gleeds Cost Management | London | 2 | 5 |
| London Economics | London | 2 | 4 |
| Nationwide Data Collection | Warwick, Ossett | 2 | 4 |
| Temple Group | West Sussex, London | 2 | 3 |
| Sia Partners | London | 2 | 2 |
| Audit One | Lanchester Road Hospital, Durham | 2 | 2 |
| Azets Holdings | Walsall | 2 | 2 |
| Binnies | Redhill | 2 | 2 |
| Consilio Global SPRL | London | 2 | 2 |
| Gridlines Group | Manchester | 2 | 2 |
| Initiate Consulting | London | 2 | 2 |
| Tracsis | Leeds, Derby | 2 | 2 |
| Cbre | London | 4 | 11 |
| Jones Lang Lasalle | London | 4 | 11 |
| Faithorn Farrell Timms | Orpington | 4 | 18 |
| Newbridge Advisors | London | 4 | 4 |
| NM Rothschild | London | 4 | 4 |
| Traderisks | London | 4 | 4 |
| Cambridge Finance | London | 4 | 3 |
| Chatham Financial | London | 4 | 3 |
| QMPF | Edinburgh | 4 | 3 |
| Resolute Asset Management | London | 4 | 3 |
| Economic Insight | London | 3 | 2 |
| Helios Technology | Farnborough | 3 | 2 |
| Centrus Financial Advisors | London | 3 | 2 |
| Government Actuarys Department | London | 3 | 2 |
| Avia Solutions | Old Woking | 3 | 3 |
| Brattle Group | Rome | 3 | 3 |
| Centurion Vat Specialists | Cardiff | 3 | 3 |
| Chase Partners | Newbury | 3 | 3 |
| Circular3 | London | 3 | 3 |
| Clarity Economic Consulting | London | 3 | 3 |
| D Fine | London | 3 | 3 |
| Flint Global | London | 3 | 3 |
| ICF SH&E | London | 3 | 3 |
| Lucerna Partners | Harrow | 3 | 3 |
| Regulatory Economics | Oxford | 3 | 3 |
| SC Advisory Services | Derby | 3 | 3 |
| Skylark Consulting Group | London | 3 | 3 |