Hargreaves Services, the AIM-listed group serving the environmental, infrastructure and property sectors, has been selected by Sizewell C Limited to deliver three foul water treatment facilities for the nuclear power project.
The work covers design, procurement, manufacture, installation, testing and commissioning.
The contract is expected to run for two years from early 2027.
Hargreaves did not disclose the value of the award.
But it is expected to contribute revenue across the financial years to May 2027 and May 2028, and to add visibility over the group's medium-term workload and order book.
Ane it said the contract should help underpin existing revenue and underlying profit before tax forecasts for both years, based on the planned phasing.
Consensus market expectations before the announcement were revenue of £292.1 million and underlying profit before tax of £17.9 million for the year to 31 May 2027.
For the year to 31 May 2028, analysts expected revenue of £305.2 million and underlying profit before tax of £18.6 million.
Simon Hicks, Hargreaves' chief executive, said: "The award reflects the growing strength of our engineering and project delivery capabilities."
