LEI: 213800ZBKL9BHSL2K459

17 March 2026

OSB GROUP PLC

(the Company)

Notification of admission to trading

48,576 ordinary shares of £0.01 each in the Company were issued, allotted and admitted to trading between 19 January 2026 and 16 March 2026 pursuant to the Company’s existing block listings for the purposes of satisfying the vesting of awards under the Company's employee share schemes.

Following this issue, and further to the Company’s six monthly return dated 01 December 2025, the Company has the following block listings totals:

Name of applicant:	OSB GROUP PLC
Name of schemes:	Sharesave Scheme Deferred Share Bonus Plan Performance Share Plan
Period of return:	From:	1 December 2025	To:	16 March 2026
Balance of unallotted securities under scheme(s) from previous return:	1,171,049 Ordinary Shares of £0.01 each 352,102 Ordinary Shares of £0.01 each 2,495,577 Ordinary Shares of £0.01 each
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):	0 Ordinary Shares of £0.01 each 0 Ordinary Shares of £0.01 each 0 Ordinary Shares of £0.01 each
Less: Number of securities issued/allotted under scheme(s) during the period of this announcement:	336,655 Ordinary Shares of £0.01 each 2,407 Ordinary Shares of £0.01 each 0 Ordinary Shares of £0.01 each
Equals: Balance under scheme(s) not yet issued/allotted at end of period:	834,394 Ordinary Shares of £0.01 each 349,695 Ordinary Shares of £0.01 each 2,495,577 Ordinary Shares of £0.01 each

Name of contact:	Jason Elphick
Telephone number of contact:	01634 848944