25 September 2017

PENNON GROUP PLC

OPTIONAL REDEMPTION NOTICE

FROM PENNON GROUP PLC

TO THE HOLDERS OF ITS

£300,000,000 PERPETUAL CAPITAL SECURITIES

(ISIN: XS0899989213)

THIS ANNOUNCEMENT RELATES TO THE DISCLOSURE OF INFORMATION THAT QUALIFIED OR MAY HAVE QUALIFIED AS INSIDE INFORMATION FOR THE PURPOSES OF ARTICLE 7 OF THE MARKET ABUSE REGULATION (EU) 596/2014.

On 11 September 2017, Pennon Group plc¹ (the Issuer) announced an invitation to holders of its £300,000,000 Perpetual Capital Securities (ISIN: XS0899989213) (the Capital Securities) to tender their Capital Securities for purchase by the Issuer for cash (the Offer). In connection with the Offer, settlement of which took place on 22 September 2017, the Issuer has purchased £285,800,000 in principal amount of the Capital Securities.

NOTICE IS HEREBY GIVEN to the Holders, the Trustee and the Principal Paying Agent in accordance with the terms and conditions of the Capital Securities (the Conditions) that the Issuer is exercising its option under Condition 5.6 to redeem all of the remaining Capital Securities on Tuesday 10 October 2017 (the Redemption Date) at their principal amount, together with periodic returns accrued from (and including) 8 March 2017 (being the Returns Payment Date immediately preceding the Redemption Date) to (but excluding) the Redemption Date.

The Issuer is entitled to exercise its option under Condition 5.6 as a result of the Issuer having purchased more than 80 per cent. of the initial aggregate principal amount of the Capital Securities.

Capitalised terms used in this announcement but not defined have the meanings given to them in the Conditions.

This announcement is released by Pennon Group plc and contains information that qualified or may have qualified as inside information for the purposes of Article 7 of the Market Abuse Regulation (EU) 596/2014 (MAR), encompassing information relating to the optional redemption of the Capital Securities described above. For the purposes of MAR and Article 2 of Commission Implementing Regulation (EU) 2016/1055, this announcement is made by Helen Barrett-Hague, Group General Counsel and Company Secretary at Pennon Group plc.

For further information please contact Paul Boote, Group Financial Controller at Pennon Group plc (telephone: 01392 443267).