| Ministry of Defence | 12,580 | 9,465 | £347,868 |
| UK Research and Innovation | 11,803 | 11,162 | £88,523 |
| UK Shared Business Services Limited | 11,030 | 10,368 | £29,012 |
| Surrey County Council | 6,923 | 6,705 | £151,289 |
| National Highways | 6,846 | 6,194 | £77,567 |
| Ministry of Justice | 6,397 | 5,765 | £273,220 |
| Suffolk County Council | 5,822 | 5,586 | £166,000 |
| Defra Network eTendering Portal | 5,699 | 4,742 | £57,168 |
| FCDO Services | 5,681 | 5,535 | £37,195 |
| Department for Education | 5,379 | 4,422 | £200,000 |
| Bristol City Council | 5,303 | 4,499 | £120,000 |
| Crown Commercial Service | 5,133 | 4,398 | £98,837 |
| Foreign, Commonwealth and Development Office | 4,758 | 3,047 | £80,000 |
| Cumbria County Council | 4,538 | 4,078 | £83,000 |
| London Borough of Haringey | 4,479 | 3,737 | £500,000 |
| Leeds City Council | 4,438 | 3,696 | £65,455 |
| Leicester City Council | 4,338 | 3,237 | £166 |
| Home Office | 4,224 | 3,499 | £187,000 |
| Milton Keynes City Council | 4,104 | 3,415 | £150,000 |
| Scottish Government | 3,965 | 3,321 | £70,000 |
| Sandwell Metropolitan Borough Council | 3,955 | 1,297 | £35,000 |
| Hampshire County Council | 3,954 | 3,353 | £126,021 |
| NHS England | 3,851 | 2,522 | £100,000 |
| University of the West of England | 3,611 | 3,539 | £43,965 |
| Department for Transport | 3,451 | 3,111 | £74,997 |
| Transport for London | 3,427 | 2,682 | £2,000,000 |
| Department for Work and Pensions | 3,381 | 3,140 | £149,810 |
| Department for Environment, Food & Rural Affairs | 3,235 | 2,504 | £49,999 |
| The University of Birmingham | 3,229 | 2,911 | £57,353 |
| Newcastle University | 3,209 | 2,905 | £51,603 |
| Department of Health and Social Care | 3,197 | 2,939 | £485,369 |
| Durham County Council | 3,155 | 2,628 | £80,000 |
| East Riding of Yorkshire Council | 3,029 | 2,531 | £72,000 |
| Derbyshire County Council | 2,999 | 1,631 | £100,000 |
| Gloucestershire County Council | 2,976 | 2,311 | £88,391 |
| Darlington Borough Council | 2,892 | 2,503 | £90,000 |
| SE Shared Services | 2,879 | 1,163 | £250,000 |
| Met Office | 2,820 | 2,736 | £24,000 |
| North Yorkshire Council | 2,796 | 2,423 | £66,541 |
| Birmingham City Council | 2,741 | 1,432 | £925,772 |
| London Borough of Enfield | 2,707 | 2,462 | £7,623 |
| City of Bradford Metropolitan District Council | 2,673 | 1,985 | £75,000 |
| Midlands and Lancashire Commissioning Support Unit | 2,541 | 2,499 | £6,500,000 |
| NHS Property Services Limited | 2,504 | 2,461 | £84,029 |
| Health Education England | 2,488 | 1,941 | £57,500 |
| Nottingham City Council | 2,476 | 1,746 | £100,000 |
| West Northamptonshire Council | 2,270 | 2,073 | £69,684 |
| Homes England (the name adopted by the Homes and Communities Agency) | 2,259 | 2,102 | £55,000 |
| Leicestershire County Council | 2,239 | 1,660 | £60,000 |
| UK Health Security Agency | 2,234 | 2,048 | £45,300 |
| Public Health England | 2,131 | 1,529 | £50,000 |
| City of London Corporation | 2,056 | 1,527 | £71,500 |
| Buckinghamshire Council | 2,044 | 1,741 | £19,733 |
| NHS Wales Shared Services Partnership - Procurement Services | 1,990 | 1,373 | £233,290 |
| NHS Arden and Greater East Midlands Commissioning Support Unit | 1,949 | 641 | £478,900 |
| H M Revenue & Customs | 1,937 | 1,847 | £68,756 |
| Environment Agency | 1,932 | 1,721 | £75,681 |
| NHS Shared Business Services | 1,922 | 711 | £600,000 |
| Suffolk Sourcing | 1,920 | 1,588 | £100,000 |
| Derby City Council | 1,912 | 1,692 | £149,288 |
| The Queen Elizabeth Hospital King's Lynn NHS Foundation Trust | 1,909 | 1,867 | £27,526 |
| University of Sheffield | 1,904 | 1,404 | £130,000 |
| Buckinghamshire County Council | 1,895 | 1,761 | £15,000 |
| Maritime and Coastguard Agency | 1,813 | 1,639 | £44,082 |
| Lincolnshire County Council | 1,762 | 1,249 | £200,000 |
| Liverpool City Council | 1,755 | 1,336 | £150,000 |
| Kirklees Council | 1,740 | 1,407 | £99,041 |
| Staffordshire County Council | 1,738 | 1,473 | £110,000 |
| Nottinghamshire County Council | 1,729 | 1,361 | £179,088 |
| Defence Science and Technology Laboratory | 1,644 | 1,530 | £78,182 |
| Sheffield City Council | 1,618 | 984 | £114,578 |
| Hull City Council | 1,614 | 1,106 | £49,999 |
| Department for Business, Energy and Industrial Strategy | 1,568 | 1,108 | £120,000 |
| Sunderland City Council | 1,568 | 1,342 | £84,950 |
| The University Of Nottingham | 1,564 | 1,256 | £62,357 |
| Lancashire County Council | 1,560 | 1,205 | £420,000 |
| London Borough of Hackney | 1,550 | 1,048 | £116,150 |
| Northern Housing Consortium Limited | 1,546 | 1,487 | £115,000 |
| North East Lincolnshire Council | 1,521 | 1,160 | £150,000 |
| Central Bedfordshire Council | 1,516 | 965 | £120,000 |
| Barnsley Metropolitan Borough Council | 1,503 | 1,130 | £88,397 |
| Hull University Teaching Hospitals NHS Trust | 1,471 | 1,357 | £24,032 |
| City of Wolverhampton Council | 1,466 | 985 | £120,000 |
| London Borough of Waltham Forest | 1,453 | 1,123 | £107,500 |
| Cumberland Council | 1,399 | 1,341 | £205,000 |
| London Borough of Hillingdon | 1,387 | 442 | £160,000 |
| Kent County Council | 1,386 | 958 | £139,012 |
| North Lincolnshire Council | 1,372 | 1,076 | £89,554 |
| Department for International Trade | 1,351 | 1,141 | £42,300 |
| NHS South, Central and West Commissioning Support Unit | 1,348 | 751 | £668,000 |
| Highways Agency | 1,320 | 1,284 | £77,840 |
| Westmorland and Furness Council | 1,304 | 1,183 | £175,000 |
| Cornwall Council | 1,291 | 670 | £140,747 |
| Sutton, Achieving for Children and Kingston | 1,291 | 1,291 | · |
| capitalEsourcing | 1,272 | 628 | £152,852 |
| United Kingdom Atomic Energy Authority | 1,271 | 485 | £150,000 |
| Newcastle City Council | 1,253 | 850 | £191,597 |
| City of Doncaster Council | 1,238 | 1,035 | £300,000 |
| West Sussex County Council | 1,231 | 984 | £250,000 |
| Somerset Council | 1,216 | 879 | £125,260 |