Block listing Interim Return

Name of applicant:

Costain Group PLC ("the Company")

Name of scheme(s):

The Company's employee Sharesave Plan.

Period of return:

From:

01 January 2020

To:

30 June 2020

Balance of unallotted securities under scheme(s) from previous return:

58,293

Plus: The amount by which the block scheme(s) has been increased since the date of the last return (if any increase has been applied for):

Nil

Less: Number of securities issued/allotted under scheme(s) during period (see LR3.5.7G):

Nil

Equals: Balance under scheme(s) not yet issued/allotted at end of period:

58,293

Name of contact:

Tracey Wood, Company Secretary

Telephone number of contact:

01628 842444

Enquiries:

Costain Group PLC

Tel: 01628 842444

Tracey Wood

Secretary

Tel: 020 3128 8100

[email protected]