| Royal Free London NHS Foundation Trust | Other | 1 | £500m | 28.3% | 2018-07-31 |
| NHS London Procurement Partnership (Hosted by Guy's and St Thomas' NHS FT) | Other | 3 | £461m | 26.1% | 2024-05-16 |
| East Of England NHS Collaborative Hub | Other | 1 | £250m | 14.1% | 2020-02-06 |
| City of London Corporation | Other | 8 | £154m | 8.7% | 2022-12-08 |
| LONDON METROPOLITAN UNIVERSITY | Other | 1 | £35m | 2.0% | 2020-11-30 |
| Kent County Council (t/a KCS Procurement Services) | Other | 1 | £33m | 1.9% | 2022-08-05 |
| University of Hertfordshire Higher Education CorporationNew | Other | 1 | £33m | 1.9% | 2026-02-04 |
| The Trustees of the British Museum | Other | 2 | £30m | 1.7% | 2022-03-14 |
| Public Health England | Other | 3 | £29m | 1.7% | 2021-07-16 |
| Fusion21 Members Consortium | Other | 6 | £28m | 1.6% | 2025-02-24 |
| Crown Commercial ServiceNew | Other | 1 | £20m | 1.1% | 2025-07-25 |
| Bradford College | Other | 5 | £17m | 1.0% | 2026-04-22 |
| Foreign Commonwealth and Development OfficeNew | Other | 1 | £16m | 0.9% | 2026-05-06 |
| UK Health Security Agency | Other | 9 | £15m | 0.8% | 2026-03-30 |
| NHS Commercial SolutionsNew | Other | 1 | £14m | 0.8% | 2024-09-01 |
| The Zoological Society of London | Other | 2 | £13m | 0.7% | 2020-06-26 |
| Arts University BournemouthNew | Other | 2 | £13m | 0.7% | 2025-10-21 |
| Natural History MuseumNew | Other | 2 | £13m | 0.7% | 2025-11-25 |
| Surrey and Borders Partnership NHS Foundation TrustNew | Other | 1 | £12m | 0.7% | 2025-01-22 |
| Barking, Havering and Redbridge University Hospitals NHS TrustNew | Other | 1 | £10m | 0.6% | 2025-09-04 |
| London Borough of HackneyNew | Other | 1 | £9m | 0.5% | 2025-01-10 |
| COUNTESS OF CHESTER HOSPITAL NHS FOUNDATION TRUST | Other | 4 | £8m | 0.4% | 2022-08-17 |
| Transport for London | Other | 1 | £6m | 0.3% | 2016-01-12 |
| UK SHARED BUSINESS SERVICES LIMITED | Other | 2 | £6m | 0.3% | 2019-11-29 |
| Science Museum Group | Other | 4 | £5m | 0.3% | 2021-03-31 |
| National Physical Laboratory | Other | 1 | £5m | 0.3% | 2021-04-01 |
| RESTORATION AND RENEWAL DELIVERY AUTHORITY LTD | Other | 2 | £4m | 0.3% | 2021-12-16 |
| UK Hydrographic OfficeNew | Other | 1 | £3m | 0.2% | 2024-06-28 |
| UNIVERSITY OF SHEFFIELD | Other | 5 | £3m | 0.2% | 2023-03-28 |
| Cornwall Council | Other | 1 | £3m | 0.2% | 2016-12-20 |
| capitalEsourcing | Other | 1 | £3m | 0.2% | 2022-06-22 |
| The Queen Elizabeth Conference CentreNew | Other | 2 | £2m | 0.1% | 2025-09-05 |
| Financial Ombudsman ServiceNew | Other | 1 | £2m | 0.1% | 2025-02-14 |
| Met Office | Other | 33 | £2m | 0.1% | 2024-05-14 |
| Health & Safety Executive | Other | 1 | £2m | 0.1% | 2023-11-01 |
| Falmouth Exeter Plus | Other | 2 | £1m | 0.1% | 2018-07-18 |
| NCG Corporation | Other | 2 | £1m | 0.1% | 2022-02-18 |
| Suffolk Academies Trust | Other | 1 | £1m | 0.1% | 2022-09-01 |
| THE UNIVERSITY OF BIRMINGHAM | Other | 7 | £940k | 0.1% | 2024-12-06 |
| UK RESEARCH & INNOVATION | Other | 1 | £679k | 0.0% | 2021-10-13 |
| Uxbridge College | Other | 1 | £578k | 0.0% | 2018-07-05 |
| BMet College | Other | 1 | £573k | 0.0% | 2022-11-11 |
| NCG | Other | 1 | £478k | 0.0% | 2022-08-22 |
| UKRI - British Geological Survey | Other | 2 | £470k | 0.0% | 2022-02-21 |
| Restoration & Renewal Delivery Authority Ltd | Other | 2 | £401k | 0.0% | 2024-05-30 |
| Information Commissioner's Office | Other | 1 | £272k | 0.0% | 2023-12-11 |
| Historic England | Other | 1 | £167k | 0.0% | 2019-06-14 |
| Birmingham Ormiston Academy | Other | 1 | £150k | 0.0% | 2021-06-22 |
| Warrington Borough Council | Other | 1 | £133k | 0.0% | 2020-03-24 |
| The Windsor Forest Colleges Group | Other | 1 | £94k | 0.0% | 2021-07-13 |
| Northumbria Healthcare Facilities ManagementNew | Other | 1 | £76k | 0.0% | 2024-12-24 |
| Bury Council | Other | 1 | £71k | 0.0% | 2020-11-30 |
| MCA - Maritime and Coastguard AgencyNew | Other | 2 | £65k | 0.0% | 2025-02-20 |
| HISTORIC ENGLAND LIMITED | Other | 1 | £64k | 0.0% | 2024-04-10 |
| British Film InstituteNew | Other | 1 | £62k | 0.0% | 2025-07-03 |
| Your Healthcare | Other | 1 | £46k | 0.0% | 2022-03-11 |
| Wirral Borough CouncilNew | Other | 1 | £35k | 0.0% | 2024-11-18 |
| Board of Trustees of the Royal Botanic Gardens Kew | Other | 1 | £32k | 0.0% | 2019-09-26 |
| CRESCENT PURCHASING LIMITED | Other | 4 | £10k | 0.0% | 2024-01-17 |
| Intellectual Property Office | Other | 1 | £10k | 0.0% | 2023-05-04 |
| CENTRE FOR PROCESS INNOVATION LIMITEDNew | Other | 2 | £0k | 0.0% | 2025-03-19 |
| Walsall Healthcare NHS Trust | Other | 1 | £0k | 0.0% | 2016-05-27 |
| London Universities Purchasing Consortium | Other | 2 | £0k | 0.0% | |
| THE UNIVERSITY OF WESTMINSTER | Other | 2 | £0k | 0.0% | |
| Westminster City Council | Other | 2 | £0k | 0.0% | |
| Imperial College Healthcare NHS Trust | Other | 1 | £0k | 0.0% | |
| Glasgow Life (Culture & Sport Glasgow) | Other | 1 | £0k | 0.0% | |
| Red Kite Learning Trust | Other | 2 | £0k | 0.0% | |
| Surrey and Borders Partnership NHS Foundation Trust on behalf of NHS Commercial Solutions | Other | 1 | £0k | 0.0% | |
| East London NHS Foundation Trust | Other | 1 | £0k | 0.0% | |
| Education | Other | 12 | £0k | 0.0% | |
| UNITED UTILITIES WATER LIMITED | Other | 1 | £0k | 0.0% | |
| University of Glasgow | Other | 1 | £0k | 0.0% | |
| Public Sector | Other | 13 | £0k | 0.0% | |
| Senedd Cymru / Welsh Parliament | Other | 1 | £0k | 0.0% | |
| Kent County Council (t/a KCS) | Other | 1 | £0k | 0.0% | |
| Student Loans Company | Other | 1 | £0k | 0.0% | |
| Financial Conduct Authority | Other | 1 | £0k | 0.0% | |
| NHS SHARED BUSINESS SERVICES LIMITED | Other | 1 | £0k | 0.0% | |
| Sheffield Hallam University | Other | 2 | £0k | 0.0% | |
| East Midlands Ambulance Service NHS Trust | Other | 1 | £0k | 0.0% | |
| UK Research & Innovation | Other | 2 | £0k | 0.0% | |