| Government Commercial Agency | Other | 7 | £252m | 30.6% | 2026-02-13 |
| Crown Commercial Service | Other | 11 | £174m | 21.1% | 2021-05-07 |
| NHS London Procurement Partnership (Hosted by Guy's and St Thomas' NHS FT) | Other | 2 | £111m | 13.5% | 2021-11-01 |
| NUCLEAR DECOMMISSIONING AUTHORITYNew | Other | 2 | £65m | 7.9% | 2024-06-18 |
| Home Office | Other | 2 | £64m | 7.7% | 2020-05-11 |
| Department of Health & Social Care | Other | 2 | £23m | 2.8% | 2021-04-08 |
| H M REVENUE & CUSTOMS | Other | 2 | £23m | 2.8% | 2026-04-02 |
| Department for Work & Pensions | Other | 1 | £23m | 2.8% | 2016-06-30 |
| Manchester University NHS Foundation TrustNew | Other | 1 | £14m | 1.7% | 2025-06-02 |
| Espo | Other | 6 | £11m | 1.3% | 2023-01-12 |
| CPS | Other | 2 | £10m | 1.2% | 2023-09-01 |
| Sellafield Ltd | Other | 1 | £7m | 0.9% | 2023-04-01 |
| HealthTrust Europe LLP (HTE) acting as agent for the University Hospitals of Coventry and Warwickshire NHS Trust (“UHCW”) | Other | 1 | £7m | 0.8% | 2020-06-15 |
| NHS SOUTH, CENTRAL AND WEST COMMISSIONING SUPPORT UNIT | Other | 13 | £6m | 0.8% | 2022-03-31 |
| Ministry of Justice | Other | 9 | £5m | 0.7% | 2026-02-27 |
| Department of Health and Social Care (DHSC) | Other | 1 | £5m | 0.6% | 2012-04-20 |
| The Insolvency Service | Other | 2 | £4m | 0.4% | 2025-12-03 |
| Department for Energy Security & Net Zero | Other | 2 | £2m | 0.3% | 2024-05-09 |
| Medicines and Healthcare Products Regulatory Agency | Other | 2 | £2m | 0.2% | 2023-11-27 |
| United Lincolnshire Teaching Hospitals NHS TrustNew | Other | 1 | £1m | 0.2% | 2025-10-08 |
| Department for Environment Food & Rural AffairsNew | Other | 1 | £1m | 0.2% | 2025-09-26 |
| Bradford Teaching Hospitals NHS Foundation Trust | Other | 1 | £1m | 0.2% | 2021-05-18 |
| Government Legal Department | Other | 1 | £1m | 0.1% | 2023-10-31 |
| FCDO ServicesNew | Other | 1 | £1m | 0.1% | 2025-09-03 |
| Norfolk and Norwich University Hospitals NHS Foundation TrustNew | Other | 1 | £955k | 0.1% | 2024-07-03 |
| Department for Education | Other | 1 | £900k | 0.1% | 2023-09-01 |
| Leicestershire Partnership NHS Trust | Other | 1 | £812k | 0.1% | 2022-05-10 |
| Nottingham City CouncilNew | Other | 1 | £800k | 0.1% | 2024-10-29 |
| Health and Safety Executive | Other | 1 | £692k | 0.1% | 2018-07-16 |
| British Transport Police | Other | 3 | £681k | 0.1% | 2025-04-02 |
| Care Quality Commission | Other | 4 | £555k | 0.1% | 2024-04-18 |
| London Borough Of IslingtonNew | Other | 1 | £437k | 0.1% | 2024-07-01 |
| Department for Culture, Media and Sport | Other | 1 | £400k | 0.0% | 2021-01-15 |
| Birmingham City University | Other | 1 | £376k | 0.0% | 2018-06-06 |
| Walsall Healthcare NHS TrustNew | Other | 1 | £372k | 0.0% | 2024-08-22 |
| Milton Keynes Council | Other | 2 | £288k | 0.0% | 2025-05-27 |
| SERIOUS FRAUD OFFICE | Other | 4 | £274k | 0.0% | 2022-12-23 |
| Humankind Charity | Other | 2 | £272k | 0.0% | 2023-04-06 |
| FINANCIAL SERVICES COMPENSATION SCHEME LIMITED | Other | 1 | £220k | 0.0% | 2021-11-23 |
| Department for International Trade | Other | 1 | £210k | 0.0% | 2015-03-02 |
| Defence Science and Technology LaboratoryNew | Other | 1 | £164k | 0.0% | 2024-12-13 |
| Cafcass | Other | 1 | £154k | 0.0% | 2023-01-04 |
| Aster Group LimitedNew | Other | 1 | £150k | 0.0% | 2026-03-21 |
| The National Archives | Other | 1 | £145k | 0.0% | 2021-12-09 |
| London Ambulance Service NHS TrustNew | Other | 1 | £140k | 0.0% | 2025-07-02 |
| OFCOM | Other | 1 | £140k | 0.0% | 2023-06-14 |
| London Borough of SuttonNew | Other | 1 | £119k | 0.0% | 2025-04-01 |
| Business Energy and Industrial Strategy | Other | 1 | £116k | 0.0% | 2020-08-06 |
| The Queen Elizabeth Hospital King's Lynn NHS Foundation Trust | Other | 3 | £111k | 0.0% | 2022-03-31 |
| BIP SOLUTIONS LIMITEDNew | Other | 1 | £110k | 0.0% | 2025-12-15 |
| Leeds City Council | Other | 1 | £108k | 0.0% | 2019-06-27 |
| DVSA - Driver and Vehicle Standards Agency | Other | 1 | £100k | 0.0% | 2024-05-21 |
| Independent Office for Police Conduct | Other | 1 | £98k | 0.0% | 2020-09-03 |
| DfTc - Department for TransportNew | Other | 3 | £88k | 0.0% | 2025-10-01 |
| Canterbury City Council | Other | 1 | £74k | 0.0% | 2021-06-11 |
| The Pensions Regulator | Other | 2 | £65k | 0.0% | 2025-11-30 |
| Buckinghamshire Council | Other | 1 | £62k | 0.0% | 2022-02-01 |
| Cabinet OfficeNew | Other | 1 | £56k | 0.0% | 2024-10-14 |
| Financial Conduct Authority | Other | 1 | £53k | 0.0% | 2018-08-31 |
| ONWARD GROUP LIMITED | Other | 1 | £53k | 0.0% | 2019-05-29 |
| Nottinghamshire Police Force | Other | 1 | £45k | 0.0% | 2018-10-13 |
| Forestry Commission | Other | 1 | £44k | 0.0% | 2021-04-01 |
| Ofsted | Other | 1 | £30k | 0.0% | 2022-07-27 |
| Midlands & Lancashire C S U | Other | 1 | £22k | 0.0% | 2023-08-23 |
| HISTORIC ENGLAND LIMITEDNew | Other | 1 | £13k | 0.0% | 2025-02-07 |
| UK SHARED BUSINESS SERVICES LIMITED | Other | 1 | £12k | 0.0% | 2024-02-15 |
| National Audit Office | Other | 1 | £6k | 0.0% | 2023-06-19 |
| Sellafield Limited | Other | 1 | £0k | 0.0% | |
| Northern Health and Social Care Trust | Other | 1 | £0k | 0.0% | |
| Northern Ireland Housing Executive | Other | 1 | £0k | 0.0% | |
| Guy's and St Thomas' NHS Foundation Trust | Other | 2 | £0k | 0.0% | |
| Barnsley Metropolitan Borough Council | Other | 1 | £0k | 0.0% | |
| HealthTrust Europe LLP (HTE) acting on behalf of | Other | 1 | £0k | 0.0% | |
| The Minister for the Cabinet Office acting through Crown Commercial Service | Other | 4 | £0k | 0.0% | |
| NHS London Procurement Partnership | Other | 1 | £0k | 0.0% | |