Contents

SHAREHOLDER INFORMATION

FINANCIAL CALENDAR

Financial year-end

31 March

Twenty-first Annual General Meeting

29 July 2010

Ex-dividend date for 2010 Final dividend

11 August 2010*

Record date for 2010 Final dividend

13 August 2010*

2010 Final dividend payable

8 October 2010*

2010/11 Half yearly financial report announcement

November 2010

2011 Interim dividend payable

April 2011

2011 Preliminary results announcement

May 2011

Twenty-second Annual General Meeting

July 2011

2011 Final dividend payable

October 2011

* the above dates are subject to obtaining shareholder approval at the 2010 Annual General Meeting to the payment of a final dividend for the year ended 31 March 2010.

Scrip Dividend Alternative

Subject to obtaining shareholder approval at the 2010 Annual General Meeting to the payment of a final dividend for the year ended 31 March 2010, the timetable for offering the Scrip Dividend Alternative will be as follows:

11 August 2010

Ordinary shares quoted ex dividend

13 August 2010

Record date for final cash dividend

27 August 2010

Posting of Scrip dividend offer

20 September 2010

Final date for receipt of Forms of Election/Mandate

7 October 2010

Posting of dividend cheques and share certificates

8 October 2010

Final cash dividend payment date

8 October 2010

First day of dealing in the new ordinary shares

Shareholders' analysis at 31 March 2010

Range

Number of shareholders

Percentage of total shareholders

Percentage of ordinary shares

1 - 100

2,441

10.06

0.02

101 - 1,000

9,555

39.40

1.41

1,001 - 5,000

10,492

43.26

6.29

5,001 - 50,000

1,433

5.91

4.40

50,001 - 100,000

80

0.33

1.58

100,001 - HIGHEST

252

1.04

86.30

24,253

100.00

100.00

Individuals

20,602

84.95

8.67

Companies

223

0.92

3.54

Trust companies (pension funds etc)

3

0.01

0.00

Banks and nominees

3,425

14.12

87.79

24,253

100.00

100.00

Further shareholder information may be found at pennon-group.co.uk.

London Stock ExchangePennon Group Plc is listed on the London Stock Exchange and meets the requirements of a Premium Listing. This is a listing that meets the more stringent UK 'super-equivalent standards' compared with a 'standard listing' which meets EU minimum standards.

SUBSTANTIAL SHAREHOLDINGS

At 14 June 2010 interests in the issued share capital had been notified pursuant to the Financial Service Authority's Disclosure and Transparency Rules:

Invesco Ltd

11.98%

Ameriprise Financial Inc

9.98%

Pictet Asset Management SA

7.24%

AXA SA and its Group Companies

6.14%

Legal & General Group Plc

5.91%

Prudential Plc

5.39%

SHAREHOLDER SERVICES

Share dealing service

The low-cost share dealing service offered by Stocktrade enables shareholders to buy and sell shares in the Company on a low-cost basis and to make regular investments in the Company. Telephone Stocktrade on 0845 601 0995 and quote: LOW CO107. Commission is 0.5% (subject to a minimum charge of £17.50) to £10,000, then 0.2% thereafter.

Change of Registrar

On 10 May 2010 the Company changed its registrar from Equiniti to Capita Registrars. Capita Registrars can be contacted as follows:

Capita Registrars
Northern House
Woodsome Park
Fenay Bridge
Huddersfield
HD8 0GA

Telephone: 0871 664 9234*
Overseas telephone: +44 800 141 2951
Email: pennon@capitaregistrars.com

*(calls cost 10p per minute plus network extras) Lines are open 8:30am - 5.30pm Mon - Fri

Share gift service

Through Sharegift, an independent charity share donation scheme, shareholders who only have a small number of shares with a value that makes it uneconomical to sell them, can donate such shares to charity. Donations can be made by completion of a simple share transfer form which is available from the Company's registrars, Capita Registrars.

Individual Savings Accounts

By holding their shares in the Company in an Individual Savings Account (ISA), shareholders may gain tax advantages.

Scrip Dividend Alternative

The Company operates a Scrip Dividend Alternative. The Scrip Dividend Alternative provides shareholders with an opportunity to invest the whole of, or part of, the cash dividend they receive on their Pennon Group Plc shares to buy further shares in the Company without incurring stamp duty or dealing expenses. Subject to obtaining shareholder approval at the 2010 Annual General Meeting to the payment of a final dividend for the year ended 31 March 2010, full details of the Scrip Dividend Alternative, including how to join, will be sent out to shareholders on 27 August 2010. The full timetable for offering the Scrip Dividend Alternative is given above.

Online portfolio service

The online portfolio service provided by Capita Registrars gives shareholders access to more information on their investments. Details of the portfolio service are available online at capitashareportal.com.

Electronic communications

The Company has passed a resolution which allows it to communicate with its shareholders by means of its website.

Shareholders currently receiving a printed copy of the Annual Report who now wish to sign up to receive all future shareholder communications electronically, can do so by registering with Capita Registrars' share portal. Go to capitashareportal.com to register, select 'Account Registration' and then follow the on-screen instructions by inputting your surname, your Investor Code (which can be found on your Form of Proxy) and your postcode as well as entering an e-mail address and selecting a password. Some facilities will require an activation code which will be sent to you in the post following registration.

Electronic Proxy voting

Shareholders also have the opportunity to register the appointment of a proxy for any general meeting of the Company once notice of the meeting has been given and may do so via capitashareportal.com Shareholders who register an 'e-mail' preference will not receive a paper proxy form. Instead they will receive an e-mail alert advising them of general meetings of the Company, with links to the Notices of Meetings and annual and half yearly accounts.

The Pennon website

Pennon's website pennon-group.co.uk provides news and details of the Company's activities plus links to its business websites. The Investor Information section contains up-to-date information for shareholders including comprehensive share price information; financial results; dividend payment dates and amounts; and Stock Exchange announcements. There is also a comprehensive share services section on the website which includes information on buying, selling and transferring shares; and on the action to be undertaken by shareholders in the event of a change in personal circumstances, for example, a change of address.

'Brokers' Contacting Shareholders - Boiler Room Scams

A number of companies, including Pennon Group Plc, continue to be aware that their shareholders have received unsolicited phone calls or correspondence concerning investment matters which imply a connection to the company concerned. These are typically from overseas based 'brokers' who target UK shareholders offering to sell them what can turn out to be worthless or high risk shares in US or UK investments. They can be very persistent and extremely persuasive and a 2006 survey by the Financial Services Authority (FSA) has reported that the average amount lost by investors is around £20,000.

It is not just the novice investor who has been duped in this way; many of the victims had been successfully investing for several years.

Shareholders are advised to be wary of any unsolicited advice, offers to buy shares at a discount or offers of free reports into the Company. If you are contacted in this manner, please make sure you obtain the correct name of the person and organisation and where they are based. You should also check that they are properly authorised by the FSA before getting involved and should call the organisation back using their details in the FSA register to verify their authorisation - you can check online fsa.gov.uk. If you deal with an unauthorised firm, you would not be eligible to receive any payment under the Financial Services Compensation Scheme. The FSA can be contacted by completing an online form at fsa.gov.uk.

Details of any share dealing facilities that the Company endorses will be included in Company mailings.

More detailed information on this or similar activity can be found on the FSA website moneymadeclear.org.uk.

Pennon Group Plc Registered Office: Peninsula House, Rydon Lane, Exeter EX2 7HR
Registered in England No. 2366640