# CPT\_24\_52 Specialist model assurance support

> A sourced UK public sector contract award published by National Audit Office.

## Key facts

- Buyer: [National Audit Office](/buyers/national-audit-office/contract-awards)
- Supplier: HARTLEY MCMASTER LIMITED
- Award value: £166,909
- Tender value: £166,909
- Award date: 6 March 2025
- Published: 26 August 2026
- Contract start: 1 April 2025
- Contract end: 31 March 2028
- Stage: awarded
- Procurement category: services
- Notice ID: 98444b10-b3fc-4053-b74a-c6612a686993-912161
- OCID: ocds-b5fd17-87bd1199-5ba8-49a7-a8f0-e1658011fe90

## Description

The National Audit Office \(NAO\) awarded a contract to Hartley McMaster Limited who will oversee and lead the testing of a subset of models with the NAO model assurance portfolio by • validation, verification and testing models and reconciling the model design back to the intended methodology\. • overseeing a small portfolio of model assurance work to ensure that outputs are successfully delivered across the NAO modelling portfolio\. • supporting the NAO to continuously improve our approach to implementing testing procedures The contract is expected to commence on Tuesday 1st April 2025 and run for an initial period of 12 months until Tuesday 31st March 2026\. The contract may be extended by 2, 12 months until Friday 31st March 2028 at the NAO's discretion\. The estimated contract value will be £111,272\.40 inclusive of VAT over the 3 years duration\. As of 1st April 2026, The current contract will also be extended for a further 12 months, from Wednesday 1 April 2026 to Wednesday 31 March 2027\. Also the original contract value of £111,272\.40 inclusive of VAT has been varied up to 50% and the new value is £166,908\.60 inclusive of VAT\. As of August 2026, this contract will expire in early January 2027 without further extension

## Related contract awards

- [CPT\_26\_39 Specialist model assurance support](/contracts/ocds-b5fd17-6bc5942d-7e5a-4ed2-900c-ae594f9e9562) — National Audit Office
- [Cyber Security Assurance and Testing Services](/contracts/ocds-b5fd17-f072b2f0-5d5c-4e76-a7b5-a8705e7e98c5) — National Audit Office
- [CPT\_23\_63 Asset Valuation](/contracts/ocds-b5fd17-99da53a2-d87c-46a6-b0d5-6750e122ccde) — National Audit Office
- [HR Advisory Services 2026/27](/contracts/ocds-b5fd17-9c64acfa-d844-4257-acec-36a3678652d4) — National Audit Office
- [Software Engineering and Application Development Services](/contracts/ocds-b5fd17-db61952b-7524-4518-bf99-64289060ebb3) — FORESTRY COMMISSION
- [Provision of General Medical Services at Tollgate Practice](/contracts/ocds-b5fd17-6b020586-1357-4c83-92d9-010ad76c2e5a) — NHS Essex Integrated Care Board
- [CWC26018 - Microsoft Cloud Solution Provider](/contracts/ocds-b5fd17-37dceafb-18f5-4f5f-9afb-ae784890924e) — Wolverhampton City Council
- [Resident Engagement and Welfare Monitoring Services Contract](/contracts/ocds-b5fd17-6c13d9dc-2d40-49d4-b478-950a598b7a82) — Housing Solutions
- [Learning Management System](/contracts/ocds-b5fd17-bc196143-dacf-41ef-a8e6-c6415526bb43) — North East Lincolnshire Council

## Source

[View the original notice on Contracts Finder](https://www.contractsfinder.service.gov.uk/Notice/98444b10-b3fc-4053-b74a-c6612a686993-912161)