---
title: "STEP Construction Partner"
ocid: "ocds-b5fd17-ea265eae-7b7b-4fa1-9582-a951015d8c27"
canonical_url: "https://d3tenders.com/contract/?ocid=ocds-b5fd17-ea265eae-7b7b-4fa1-9582-a951015d8c27"
markdown_url: "https://d3tenders.com/contract/ocds-b5fd17-ea265eae-7b7b-4fa1-9582-a951015d8c27.md"
json_url: "https://d3tenders.com/contract/ocds-b5fd17-ea265eae-7b7b-4fa1-9582-a951015d8c27.json"
source: "Contracts Finder"
current_stage: "Award"
buyer: "UK ATOMIC ENERGY AUTHORITY"
published: "2026-04-22"
---

# STEP Construction Partner

Buyer: UK ATOMIC ENERGY AUTHORITY  
Current stage: Award  
OCID: ocds-b5fd17-ea265eae-7b7b-4fa1-9582-a951015d8c27

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## Summary

The UK Atomic Energy Authority, located at Culham Campus, Abingdon, has completed its procurement process titled "STEP Construction Partner" under the industry category of engineering works and construction works. This selective procurement was conducted through competitive dialogue for Lot 2: Construction Partner (CP), which is the sole focus of the contract after the cancellation of Lot 1: Engineering Partner. The procurement aims to bring together industrial capabilities to design and build a prototype fusion energy plant—an endeavour led by the UK Fusion Energy (UKFE). Key dates include the contract award on 2nd April 2026, with a term expiring on 31st March 2029, allowing optional extensions over the next 20 years. The estimated contract value is £10,000,000,000, and the delivery locations span the United Kingdom and other regions, including British Overseas Territories and Europe.

This procurement offers substantial growth opportunities for businesses specialising in construction, engineering, and related services. Given the project's scale and international reach, companies with experience in complex engineering and project management are well-suited to compete. The aim to develop a world-leading fusion delivery industry provides scope for innovative solutions in energy engineering, particularly for those with expertise in structural, mechanical, and electrical engineering. Small and medium-sized enterprises (SMEs) can also engage, facilitating industry diversity and fostering new partnerships. The scale of the project, combined with its strategic importance in energy innovation, makes it a prime opportunity for businesses seeking to expand their footprint in the global engineering and construction sector. ILIOS, identified as the supplier, exemplifies the type of large-scale company involved.

## Notice

UKIFS (now UKFE) has conducted this Procurement for a Construction Partner, who, together with a Fusion Partner (determined to be United Kingdom Atomic Energy Authority (UKAEA)), will bring together and develop extensive industrial capabilities to design and build a UK prototype fusion energy plant capable of delivering net-energy to the grid, and build a world-leading fusion delivery industry. The Procurement was originally divided into two lots: * Lot 1: Engineering Partner (EP) * Lot 2: Construction Partner (CP) However, Lot 1 - EP has since been cancelled. Lot 2 - CP is now the only Lot included in this Procurement exercise. The contract term for Lot 2 will expire 31 March 2029, followed by three (3) optional extension periods of four (4), six (6) and seven (7) years. UKFE will have the right to exercise an extension option at six (6) months' notice. The maximum contract duration will be twenty (20) years with an estimated value of PS10,000,000,000 across this period.

## Key Details

| Field | Value |
| --- | --- |
| Publication source | Contracts Finder |
| Latest notice | https://www.contractsfinder.service.gov.uk/Notice/55501510-06d2-4ce2-a694-cc4b78f6e508 |
| Notice type | Award Notice |
| Procurement type | Standard |
| Procurement category | Works |
| Procurement method | Selective |
| Procurement method details | Competitive dialog |
| Tender suitability | SME |
| Awardee scale | Large |
| All stages | Award |

## Dates

| Field | Value |
| --- | --- |
| Publication date | 22 Apr 2026 |
| Submission deadline | 17 Jul 2024 |
| Future notice date | Not specified |
| Award date | 1 Apr 2026 |
| Contract period | 1 Apr 2026 - 31 Mar 2029 |
| Recurrence | Not specified |

## Values

| Field | Value |
| --- | --- |
| Tender value | £1 |
| Lots value | Not specified |
| Awards value | £10,000,000,000 |
| 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 | UK ATOMIC ENERGY AUTHORITY |
| Locality | ABINGDON |
| Post town | Oxford |
| Postcode | OX14 3DB |
| Country | England |
| ITL 1 | TLJ South East (England) |
| ITL 2 | TLJ1 Berkshire, Buckinghamshire and Oxfordshire |
| ITL 3 | TLJ14 Oxfordshire CC |
| Local authority | South Oxfordshire |
| Electoral ward | Sandford & the Wittenhams |
| Westminster constituency | Didcot and Wantage |
| Delivery location | Not specified |

## Supplier

| Field | Value |
| --- | --- |
| Number of suppliers | 1 |
| Supplier names | ILIOS |

## CPV Codes

### Divisions

- 45 - Construction work
- 66 - Financial and insurance services
- 71 - Architectural, construction, engineering and inspection services

### Codes

- 45200000 - Works for complete or part construction and civil engineering work
- 45220000 - Engineering works and construction works
- 66519000 - Engineering, auxiliary, average, loss, actuarial and salvage insurance services
- 71000000 - Architectural, construction, engineering and inspection services
- 71240000 - Architectural, engineering and planning services
- 71250000 - Architectural, engineering and surveying services
- 71300000 - Engineering services
- 71310000 - Consultative engineering and construction services
- 71311000 - Civil engineering consultancy services
- 71312000 - Structural engineering consultancy services
- 71313000 - Environmental engineering consultancy services
- 71318000 - Advisory and consultative engineering services
- 71320000 - Engineering design services
- 71321000 - Engineering design services for mechanical and electrical installations for buildings
- 71322000 - Engineering design services for the construction of civil engineering works
- 71323000 - Engineering-design services for industrial process and production
- 71323200 - Plant engineering design services
- 71330000 - Miscellaneous engineering services
- 71333000 - Mechanical engineering services
- 71334000 - Mechanical and electrical engineering services
- 71336000 - Engineering support services
- 71337000 - Corrosion engineering services
- 71340000 - Integrated engineering services
- 71350000 - Engineering-related scientific and technical services
- 71540000 - Construction management services

## Release History

- 22 Apr 2026 at 13:00 - Award - Award Notice - https://www.contractsfinder.service.gov.uk/Notice/55501510-06d2-4ce2-a694-cc4b78f6e508

## Documents

- https://www.contractsfinder.service.gov.uk/Notice/55501510-06d2-4ce2-a694-cc4b78f6e508
  22nd April 2026 - Awarded contract notice on Contracts Finder
- https://uk.eu-supply.com/app/rfq/editdocuments_b.asp?PID=81210&TID=86951&PJID=1753&FID=0
  Additional data
- https://uk.eu-supply.com/ctm/Company/CompanyInformation/Index/72814
  User / Company

## Notice URLs

- https://www.gov.uk/government/organisations/uk-fusion-energy

## Provenance

This Markdown file is an alternate public rendering of the D3 Tenders contract record. The canonical page is https://d3tenders.com/contract/?ocid=ocds-b5fd17-ea265eae-7b7b-4fa1-9582-a951015d8c27. The underlying structured data is available as OCDS JSON at https://d3tenders.com/contract/ocds-b5fd17-ea265eae-7b7b-4fa1-9582-a951015d8c27.json.