---
title: "CPT_24_52 Specialist model assurance support"
ocid: "ocds-b5fd17-87bd1199-5ba8-49a7-a8f0-e1658011fe90"
canonical_url: "https://d3tenders.com/contract/?ocid=ocds-b5fd17-87bd1199-5ba8-49a7-a8f0-e1658011fe90"
markdown_url: "https://d3tenders.com/contract/ocds-b5fd17-87bd1199-5ba8-49a7-a8f0-e1658011fe90.md"
json_url: "https://d3tenders.com/contract/ocds-b5fd17-87bd1199-5ba8-49a7-a8f0-e1658011fe90.json"
source: "Contracts Finder"
current_stage: "Award"
buyer: "NATIONAL AUDIT OFFICE"
published: "2026-03-09"
---

# CPT_24_52 Specialist model assurance support

Buyer: NATIONAL AUDIT OFFICE  
Current stage: Award  
OCID: ocds-b5fd17-87bd1199-5ba8-49a7-a8f0-e1658011fe90

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## Summary

The National Audit Office (NAO) has successfully awarded a contract titled "CPT_24_52 Specialist Model Assurance Support" to Hartley McMaster Limited, reflecting the completion of the awarding stage of the procurement process. This contract, within the System Quality Assurance Assessment and Review Services industry, is primarily aimed at enhancing the NAO's model assurance portfolio through validation, verification, and testing of models. The procurement process was conducted as an open procedure, adhering to the below-threshold procurement method. The contract commenced on 1st April 2025, with an initial term ending on 31st March 2026, and includes potential extensions up to 2028. The procurement took place entirely within the United Kingdom, showcasing the NAO's commitment to bolstering service quality in public expenditure audits. The total varied contract value is now £166,908.60 including VAT.

This contract provides substantial growth opportunities for small and medium-sized enterprises (SMEs) and voluntary, community, and social enterprises (VCSEs), as the NAO particularly encourages participation from these sectors. Businesses centred on quality assurance, auditing services, and those with a robust capacity for model validation and verification will find this contract particularly suited to their capabilities. By overseeing and advancing the NAO's model assurance procedures, successful suppliers can not only fortify their reputation in public sector services but also leverage this experience to secure future contracts within the realm of quality assurance and auditing services.

## Notice

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 PS111,272.40 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 PS111,272.40 inclusive of VAT has been varied up to 50% and the new value is PS166,908.60 inclusive of VAT.

## Key Details

| Field | Value |
| --- | --- |
| Publication source | Contracts Finder |
| Latest notice | https://www.contractsfinder.service.gov.uk/Notice/98444b10-b3fc-4053-b74a-c6612a686993 |
| Notice type | Award Notice |
| Procurement type | Standard |
| Procurement category | Services |
| Procurement method | Open |
| Procurement method details | Open procedure (below threshold) |
| Tender suitability | SME, VCSE |
| Awardee scale | SME |
| All stages | Tender, Award |

## Dates

| Field | Value |
| --- | --- |
| Publication date | 9 Mar 2026 |
| Submission deadline | 10 Feb 2025 |
| Future notice date | Not specified |
| Award date | 6 Mar 2025 |
| Contract period | 31 Mar 2025 - 31 Mar 2028 |
| Recurrence | Not specified |

## Values

| Field | Value |
| --- | --- |
| Tender value | £166,908 |
| Lots value | Not specified |
| Awards value | £166,908 |
| Contracts value | Not specified |

## Status

| Field | Value |
| --- | --- |
| Tender status | Complete |
| Lots status | Not specified |
| Awards status | Active |
| Contracts status | Not specified |

## Buyer

| Field | Value |
| --- | --- |
| Main buyer | NATIONAL AUDIT OFFICE |
| Locality | LONDON |
| Post town | South West London |
| Postcode | SW1W 9SP |
| Country | England |
| ITL 1 | TLI London |
| ITL 2 | TLI3 Inner London - West |
| ITL 3 | TLI35 Westminster and City of London |
| Local authority | Westminster |
| Electoral ward | Pimlico North |
| Westminster constituency | Cities of London and Westminster |
| Delivery location | Not specified |

## Supplier

| Field | Value |
| --- | --- |
| Number of suppliers | 1 |
| Supplier names | HARTLEY MCMASTER |

## CPV Codes

### Divisions

- 72 - IT services: consulting, software development, Internet and support
- 79 - Business services: law, marketing, consulting, recruitment, printing and security

### Codes

- 72225000 - System quality assurance assessment and review services
- 79212000 - Auditing services

## Release History

- 9 Mar 2026 at 09:40 - AwardUpdate - Award Notice - https://www.contractsfinder.service.gov.uk/Notice/98444b10-b3fc-4053-b74a-c6612a686993
- 20 Mar 2025 at 09:36 - Award - Award Notice - https://www.contractsfinder.service.gov.uk/Notice/98444b10-b3fc-4053-b74a-c6612a686993
- 15 Jan 2025 at 10:06 - Tender - Tender Notice - https://www.contractsfinder.service.gov.uk/Notice/46575de9-843c-4b89-838f-28cb1bc0c3c0

## Documents

- https://www.contractsfinder.service.gov.uk/Notice/98444b10-b3fc-4053-b74a-c6612a686993
  9th March 2026 - Awarded contract notice on Contracts Finder
- https://www.contractsfinder.service.gov.uk/Notice/46575de9-843c-4b89-838f-28cb1bc0c3c0
  15th January 2025 - Opportunity notice on Contracts Finder

## Provenance

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