AGM Statement

Trading in Line with Board Expectations

Ahead of today's Annual General Meeting ("AGM"), Costain Group PLC ("Costain" or the "Group") announces an update on trading for the period 1 January 2024 to date.

Costain confirms that trading for the period is in line with Board expectations and the Group continues to have a high-quality forward work position that aligns with its strategic plans for both the Transportation and Natural Resources divisions.

Since the start of the year, contract wins include:

• bp's Net Zero Teesside Power and Northern Endurance Partnership joint ventures: to manage onshore CO2 gathering systems for the East Coast Cluster;
• Northumbrian Water: to help shape and deliver its strategic infrastructure upgrade programme (including AMP8) with the potential value of up to £670m to Costain during a 12-year period;
• Thames Water: award of a Design and Build contract to upgrade two strategic water treatment assets in Berkshire and Hampshire;
• Transport for London (TfL): two major road refurbishment projects at Gallows Corner Flyover and Brent Cross Interchange; and
• Two new framework contracts in the nuclear energy sector.

The average weekly net cash position from 1 January to 30 April 2024 was £168.8m (of which £60.4m was held in joint ventures). The average weekly net cash position for the same period last year was £122.9m (of which £57.2m was held in joint ventures).

The Group is in line to deliver its margin targets of an adjusted operating margin run-rate of 3.5% during the course of 2024 and 4.5% during the course of 2025. While the Board is mindful of the macro-economic backdrop, it remains confident in the Group's strategy and medium to long-term prospects.

As part of the AGM presentation, Costain will provide a short business update drawing on information published on 12 March 2024. There will be no new material information in the presentation further to that of 12 March 2024 and today's announcement.