| Ministry of Justice | Other | 11 | £4.3bn | 64.3% | 2025-04-01 |
| Crown Commercial Service | Other | 3 | £603m | 9.0% | 2025-10-14 |
| H M REVENUE & CUSTOMS | Other | 2 | £506m | 7.5% | 2024-11-21 |
| NHS London Procurement Partnership (Hosted by Guy's and St Thomas' NHS FT) | Other | 2 | £322m | 4.8% | 2022-07-06 |
| Department of Health & Social Care | Other | 3 | £223m | 3.3% | 2021-01-13 |
| Ministry of Defence | Other | 4 | £210m | 3.1% | 2024-09-01 |
| University of Greenwich | Other | 1 | £105m | 1.6% | 2020-05-17 |
| Defence Infrastructure Organisation | Other | 1 | £90m | 1.3% | 2016-08-16 |
| Ministry of Defence, DIO, Defence Infrastructure Organisation (DIO) | Other | 1 | £90m | 1.3% | 2016-08-05 |
| Department for Work & Pensions | Other | 1 | £61m | 0.9% | 2017-05-24 |
| HM Revenue & Customs | Other | 3 | £57m | 0.9% | 2019-03-26 |
| Construction Industry Training Board | Other | 7 | £18m | 0.3% | 2024-05-08 |
| UK Health Security Agency | Other | 12 | £16m | 0.2% | 2023-05-05 |
| Scottish Fire and Rescue Service : Scottish Fire and Rescue Service | Other | 1 | £16m | 0.2% | 2018-11-23 |
| Chesterfield Royal Hospital NHS Foundation Trust | Other | 1 | £15m | 0.2% | 2018-01-01 |
| Espo | Other | 4 | £14m | 0.2% | 2022-09-01 |
| Solent University | Other | 1 | £12m | 0.2% | 2020-06-15 |
| The Litmus Partnership Ltd | Other | 4 | £11m | 0.2% | 2019-08-12 |
| Avon & Somerset Constabulary | Other | 1 | £8m | 0.1% | 2019-06-13 |
| Transport for LondonNew | Other | 3 | £6m | 0.1% | 2025-11-13 |
| City of London Corporation | Other | 1 | £5m | 0.1% | 2018-07-02 |
| University Hospitals Birmingham NHS Foundation Trust | Other | 2 | £4m | 0.1% | 2022-02-16 |
| Department of Health and Social Care (DHSC) | Other | 1 | £3m | 0.0% | 2021-02-17 |
| NHS SOUTH, CENTRAL AND WEST COMMISSIONING SUPPORT UNIT | Other | 1 | £3m | 0.0% | 2017-07-20 |
| University of Northumbria | Other | 1 | £978k | 0.0% | 2018-07-04 |
| The Insolvency Service | Other | 1 | £750k | 0.0% | 2023-02-02 |
| Yorkshire Housing Ltd | Other | 1 | £520k | 0.0% | 2016-03-15 |
| NHS Improvements | Other | 1 | £379k | 0.0% | 2020-02-06 |
| South West London & St. Georges Mental Health NHS Trust | Other | 1 | £331k | 0.0% | 2017-01-06 |
| DEFRA | Other | 1 | £300k | 0.0% | 2023-10-12 |
| Lancashire County Council | Other | 3 | £276k | 0.0% | 2020-03-06 |
| UNIVERSITY OF SUSSEX(THE) | Other | 1 | £170k | 0.0% | 2023-11-13 |
| Your Housing Group Ltd, acting on behalf of itself and its current and future subsidiaries | Other | 1 | £87k | 0.0% | 2018-05-01 |
| Newcastle University | Other | 1 | £53k | 0.0% | 2019-10-29 |
| Homes England (the name adopted by the Homes and Communities Agency) | Other | 2 | £45k | 0.0% | 2023-11-15 |
| Stonewater Limited | Other | 1 | £40k | 0.0% | 2016-04-01 |
| St Albans City & District | Other | 1 | £28k | 0.0% | 2022-09-01 |
| London Borough of Merton | Other | 1 | £25k | 0.0% | 2020-06-08 |
| Frimley Health NHS Foundation Trust | Other | 1 | £23k | 0.0% | 2022-11-28 |
| Health Education England | Other | 1 | £16k | 0.0% | 2022-05-03 |
| Hampshire County Council | Other | 1 | £0k | 0.0% | 2017-10-23 |
| London Universities Purchasing Consortium | Other | 3 | £0k | 0.0% | 2023-04-24 |
| YORK AND SCARBOROUGH TEACHING HOSPITALS NHS FOUNDATION TRUST | Other | 1 | £0k | 0.0% | 2017-04-25 |
| NOE CPC | Other | 1 | £0k | 0.0% | 2017-04-25 |
| Scottish Parliament | Other | 2 | £0k | 0.0% | |
| Surrey and Borders Partnership NHS Foundation Trust on behalf of NHS Commercial Solutions | Other | 1 | £0k | 0.0% | |
| National Galleries of Scotland | Other | 1 | £0k | 0.0% | |
| North Ayrshire Council | Other | 8 | £0k | 0.0% | |
| Scottish Fire and Rescue Service | Other | 2 | £0k | 0.0% | |
| The Common Services Agency (more commonly known as NHS National Services Scotland) (NSS) | Other | 3 | £0k | 0.0% | |
| University of Dundee | Other | 1 | £0k | 0.0% | |
| The Minister for the Cabinet Office acting through Crown Commercial Service | Other | 1 | £0k | 0.0% | |
| The Mersey Docks and Harbour Company | Other | 1 | £0k | 0.0% | |