| NHS London Procurement Partnership (Hosted by Guy's and St Thomas' NHS FT) | Other | 2 | £322m | 28.1% | 2022-07-06 |
| East Of England NHS Collaborative Hub | Other | 1 | £250m | 21.8% | 2020-02-06 |
| Crown Commercial ServiceNew | Other | 1 | £215m | 18.8% | 2026-01-14 |
| Ministry of Justice | Other | 1 | £75m | 6.5% | 2017-11-20 |
| Cambridgeshire County CouncilNew | Other | 1 | £54m | 4.7% | 2025-03-20 |
| Espo | Other | 7 | £35m | 3.1% | 2025-05-16 |
| The Royal Borough of Kensington and Chelsea Tenant Management Organisation Ltd ("KCTMO") | Other | 1 | £29m | 2.5% | 2016-09-26 |
| North of England Commercial Procurement Collaborative (NOE CPC) | Other | 1 | £29m | 2.5% | 2018-03-31 |
| London Borough of WandsworthNew | Other | 6 | £18m | 1.6% | 2025-11-11 |
| UK Health Security AgencyNew | Other | 1 | £18m | 1.6% | 2025-01-14 |
| Transport for London | Other | 1 | £17m | 1.5% | 2016-07-29 |
| Fusion21 Members ConsortiumNew | Other | 5 | £16m | 1.4% | 2025-02-24 |
| Hull University Teaching Hospitals NHS TrustNew | Other | 3 | £12m | 1.1% | 2025-05-01 |
| Harris FederationNew | Other | 4 | £7m | 0.6% | 2026-03-11 |
| YORK TEACHING HOSPITAL NHS FOUNDATION TRUST | Other | 1 | £6m | 0.5% | 2022-01-14 |
| University of Sunderland in LondonNew | Other | 2 | £5m | 0.4% | 2025-01-24 |
| Choice Housing Ireland LimitedNew | Other | 3 | £5m | 0.4% | 2025-12-09 |
| UNIVERSITY OF GLOUCESTERSHIRE | Other | 2 | £4m | 0.3% | 2020-06-09 |
| University of South Wales | Other | 2 | £3m | 0.3% | 2016-05-16 |
| West Midlands Combined AuthorityNew | Other | 1 | £3m | 0.3% | 2024-12-19 |
| London Borough of Enfield | Other | 2 | £3m | 0.2% | 2022-04-21 |
| CTM Portal for the NDA Shared Services Alliance | Other | 1 | £2m | 0.2% | 2022-01-28 |
| N H S Shared Business ServicesNew | Other | 1 | £2m | 0.2% | 2024-09-13 |
| The Rotherham NHS Foundation Trust | Other | 1 | £2m | 0.2% | 2019-09-04 |
| The Organising Committee for the 2022 Birmingham Commonwealth Games Ltd | Other | 3 | £2m | 0.2% | 2021-08-12 |
| Solihull CollegeNew | Other | 1 | £2m | 0.1% | 2024-06-11 |
| London Ambulance Service NHS TrustNew | Other | 1 | £2m | 0.1% | 2026-02-20 |
| Home Office | Other | 1 | £2m | 0.1% | 2019-03-31 |
| MANCHESTER CENTRAL CONVENTION COMPLEX LIMITED | Other | 1 | £1m | 0.1% | 2017-02-24 |
| Sanctuary Housing GroupNew | Other | 1 | £1m | 0.1% | 2025-04-30 |
| Light Hall School | Other | 2 | £1m | 0.1% | 2024-05-24 |
| Royal Free London NHS Foundation TrustNew | Other | 1 | £754k | 0.1% | 2025-07-22 |
| Met Office | Other | 2 | £595k | 0.1% | 2019-01-14 |
| Simply Serve Ltd | Other | 4 | £558k | 0.0% | 2025-05-19 |
| LONDON GATEWAY PORT LIMITEDNew | Other | 1 | £452k | 0.0% | 2026-04-01 |
| B:Music LtdNew | Other | 1 | £335k | 0.0% | 2024-12-16 |
| Leicester City CouncilNew | Other | 1 | £333k | 0.0% | 2024-08-31 |
| ENGIE SERVICES LIMITED | Other | 1 | £195k | 0.0% | 2021-03-15 |
| Homes and Communities Agency | Other | 1 | £137k | 0.0% | 2017-06-16 |
| SOMERSET NHS FOUNDATION TRUSTNew | Other | 2 | £58k | 0.0% | 2026-04-01 |
| Birmingham Women's and Children's NHS Foundation Trust | Other | 1 | £54k | 0.0% | 2019-03-07 |
| UNIVERSITY OF LANCASTER | Other | 1 | £50k | 0.0% | 2022-04-29 |
| Hertfordshire NHS Procurement | Other | 1 | £45k | 0.0% | 2020-09-01 |
| NHS EnglandNew | Other | 1 | £31k | 0.0% | 2025-10-10 |
| O F W A TNew | Other | 1 | £17k | 0.0% | 2026-03-10 |
| Lee Valley Regional Park Authority | Other | 1 | £3k | 0.0% | 2020-03-27 |
| University of SussexNew | Other | 1 | £0k | 0.0% | 2025-07-07 |
| NOE CPC | Other | 2 | £0k | 0.0% | 2019-12-13 |
| University for the Creative Arts | Other | 1 | £0k | 0.0% | 2019-01-04 |
| CRESCENT PURCHASING LIMITED | Other | 1 | £0k | 0.0% | 2017-08-08 |
| Caledonian Sleeper Limited | Other | 1 | £0k | 0.0% | |
| GOVERNMENT PROPERTY AGENCY | Other | 1 | £0k | 0.0% | |
| RED BOX CONSULTANCY SERVICES LIMITED | Other | 1 | £0k | 0.0% | |
| Crown Office and Procurator Fiscal Service | Other | 2 | £0k | 0.0% | |
| Cardiff University | Other | 2 | £0k | 0.0% | |
| Southern Electric Power Distribution plc | Other | 1 | £0k | 0.0% | |
| Chadwell Heath Academy | Other | 1 | £0k | 0.0% | |
| North of England Commercial Procurement Collaborative (NOE CPC) (hosted by and acting through Leeds and York Partnership NHS Foundation Trust.) | Other | 1 | £0k | 0.0% | |
| Translink | Other | 2 | £0k | 0.0% | |
| The Police and Crime Commissioner for Warwickshire | Other | 1 | £0k | 0.0% | |
| University Of Edinburgh | Other | 2 | £0k | 0.0% | |
| Highlands and Islands Airports Limited | Other | 1 | £0k | 0.0% | |
| University of Glasgow | Other | 1 | £0k | 0.0% | |
| NHS SHARED BUSINESS SERVICES LIMITED | Other | 3 | £0k | 0.0% | |
| Dounreay Site Restoration Limited | Other | 1 | £0k | 0.0% | |
| West London NHS Trust | Other | 1 | £0k | 0.0% | |
| UNIVERSITY OF SUSSEX(THE) | Other | 1 | £0k | 0.0% | |
| Northern Ireland Housing Executive | Other | 1 | £0k | 0.0% | |