Blocklisting Interim Review

Centrica PLC SCHEDULE 5 BLOCKLISTING SIX MONTHLY RETURN 1. Name of company Centrica plc 2. Name of scheme Centrica Sharesave scheme 3. Period of return: From 01/11/2006 to 30/04/2007 4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period 1,502,325 ORDINARY 6 14/81p 5. Number of shares issued/allotted under scheme during period 1,848,694 ORDINARY 6 14/81p 6. Balance under scheme not yet issued/allotted at end of period 24,653,631 ORDINARY 6 14/81p 7. Number and class of share(s) (amount of stock/debt securities) originally listed and the date of admission 8,246,046 ORDINARY 6 14/81p 25/10/2004 10,000,000 ORDINARY 6 14/81p 24/03/2005 25,000,000 ORDINARY 6 14/81p 27/04/2006 25,000,000 ORDINARY 6 14/81p 24/04/2007 Please confirm total number of shares in issue at the end of the period in order for us to update our records 3,669,877,696 as at 30 April 2007 Contact for Queries: Name: Philip Davies Tel: 01753 494 012 Address: Centrica plc, Millstream, Maidenhead Road, Windsor, Berks SL4 5GD SCHEDULE 5 BLOCKLISTING SIX MONTHLY RETURN 1. Name of company Centrica plc 2. Name of scheme Centrica Executive Share Option scheme 3. Period of return: From 01/11/2006 to 30/04/2007 4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period 1,168,847 ORDINARY 6 14/81p 5. Number of shares issued/allotted under scheme during period 1,858,181 ORDINARY 6 14/81p 6. Balance under scheme not yet issued/allotted at end of period 9,310,666 ORDINARY 6 14/81p 7. Number and class of share(s) (amount of stock/debt securities) originally listed and the date of admission 2,628,006 ORDINARY 6 14/81p 25/10/2004 5,000,000 ORDINARY 6 14/81p 04/04/2005 10,000,000 ORDINARY 6 14/81p 24/03/2006 10,000,000 ORDINARY 6 14/81p 24/04/2007 Please confirm total number of shares in issue at the end of the period in order for us to update our records 3,669,877,696 as at 30 April 2007 Contact for Queries: Name: Philip Davies Tel: 01753 494 012 Address: Centrica plc, Millstream, Maidenhead Road, Windsor, Berks SL4 5GD SCHEDULE 5 BLOCKLISTING SIX MONTHLY RETURN 1. Name of company Centrica plc 2. Name of scheme Centrica Share Incentive Plan 3. Period of return: From 01/11/2006 to 30/04/2007 4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period 818,276 ORDINARY 6 14/81p 5. Number of shares issued/allotted under scheme during period 270,129 ORDINARY 6 14/81p 6. Balance under scheme not yet issued/allotted at end of period 548,147 ORDINARY 6 14/81p 7. Number and class of share(s) (amount of stock/debt securities) originally listed and the date of admission 265,283 ORDINARY 6 14/81p 25/10/2004 2,000,000 ORDINARY 6 14/81p 17/02/2005 Please confirm total number of shares in issue at the end of the period in order for us to update our records 3,669,877,696 as at 30 April 2007 Contact for Queries: Name: Philip Davies Tel: 01753 494 012 Address: Centrica plc, Millstream, Maidenhead Road, Windsor, Berks SL4 5GD SCHEDULE 5 BLOCKLISTING SIX MONTHLY RETURN 1. Name of company Centrica plc 2. Name of scheme Centrica Long Term Incentive Scheme 3. Period of return: From 01/11/2006 to 30/04/2007 4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period 2,440,234 ORDINARY 6 14/81p 5. Number of shares issued/allotted under scheme during period 4,475,228 ORDINARY 6 14/81p 6. Balance under scheme not yet issued/allotted at end of period 965,006 ORDINARY 6 14/81p 7. Number and class of share(s) (amount of stock/debt securities) originally listed and the date of admission 10,000,000 ORDINARY 6 14/81p 03/03/2006 3,000,000 ORDINARY 6 14/81p 28/03/2007 Please confirm total number of shares in issue at the end of the period in order for us to update our records 3,669,877,696 as at 30 April 2007 Contact for Queries: Name: Philip Davies Tel: 01753 494 012 Address: Centrica plc, Millstream, Maidenhead Road, Windsor, Berks SL4 5GD SCHEDULE 5 BLOCKLISTING SIX MONTHLY RETURN 1. Name of company Centrica plc 2. Name of scheme Centrica Share Award Scheme 3. Period of return: From 01/11/2006 to 30/04/2007 4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period 0 ORDINARY 6 14/81p 5. Number of shares issued/allotted under scheme during period 0 ORDINARY 6 14/81p 6. Balance under scheme not yet issued/allotted at end of period 2,000,000 ORDINARY 6 14/81p 7. Number and class of share(s) (amount of stock/debt securities) originally listed and the date of admission 2,000,000 ORDINARY 6 14/81p 24/08/2006 Please confirm total number of shares in issue at the end of the period in order for us to update our records 3,669,877,696 as at 30 April 2007 Contact for Queries: Name: Philip Davies Tel: 01753 494 012 Address: Centrica plc, Millstream, Maidenhead Road, Windsor, Berks SL4 5GD SCHEDULE 5 BLOCKLISTING SIX MONTHLY RETURN 1. Name of company Centrica plc 2. Name of scheme Centrica North American Share Purchase Plan 3. Period of return: From 01/11/2006 to 30/04/2007 4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period 0 ORDINARY 6 14/81p 5. Number of shares issued/allotted under scheme during period 7,072 ORDINARY 6 14/81p 6. Balance under scheme not yet issued/allotted at end of period 42,928 ORDINARY 6 14/81p 7. Number and class of share(s) (amount of stock/debt securities) originally listed and the date of admission 50,000 ORDINARY 6 14/81p 22/01/2007 Please confirm total number of shares in issue at the end of the period in order for us to update our records 3,669,877,696 as at 30 April 2007 Contact for Queries: Name: Philip Davies Tel: 01753 494 012 Address: Centrica plc, Millstream, Maidenhead Road, Windsor, Berks SL4 5GD

Companies

Centrica (CNA)
UK 100