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: 01/05/2012 to 31/10/12

4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period

18,847,233 ORDINARY 6 14/81p

5. Number of shares issued/allotted under scheme during period

13,184,222 ORDINARY 6 14/81p

6. Balance under scheme not yet issued/allotted at end of period

5,663,011 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
18,000,000 ORDINARY 6 14/81p 15/04/2008
36,000,000 ORDINARY 6 14/81p 06/05/2009

8. Please confirm total number of shares in issue at the end of the period in order for us to update our records

5,198,436,308 as at 31 October 2012

Contact for Queries:

Name: Claire Spencer
Tel: 01753 494007

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: 01/05/2012 to 31/10/12

4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period

3,616,710 ORDINARY 6 14/81p

5. Number of shares issued/allotted under scheme during period

448,291 ORDINARY 6 14/81p

6. Balance under scheme not yet issued/allotted at end of period

3,168,419 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
10,000,000 ORDINARY 6 14/81p 06/05/2009
2,373,098 ORDINARY 6 14/81p 05/04/2011

8. Please confirm total number of shares in issue at the end of the period in order for us to update our records

5,198,436,308 as at 31 October 2012

Contact for Queries:

Name: Claire Spencer

Tel: 01753 494007

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: 01/05/2012 to 31/10/12

4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period

1,845,374 ORDINARY 6 14/81p

5. Number of shares issued/allotted under scheme during period

532,212 ORDINARY 6 14/81p

6. Balance under scheme not yet issued/allotted at end of period

1,313,162 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
500,000 ORDINARY 6 14/81p 15/04/2008
5,000,000 ORDINARY 6 14/81p 06/05/2009

8. Please confirm total number of shares in issue at the end of the period in order for us to update our records

5,198,436,308 as at 31 October 2012

Contact for Queries:

Name: Claire Spencer

Tel: 01753 494007

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: 01/05/2012 to 31/10/12

4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period

6,641,766 ORDINARY 6 14/81p

5. Number of shares issued/allotted under scheme during period

156,844 ORDINARY 6 14/81p

6. Balance under scheme not yet issued/allotted at end of period

6,484,922 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
10,000,000 ORDINARY 6 14/81p 15/04/2008
10,000,000 ORDINARY 6 14/81p 06/05/2009
6,000,000 ORDINARY 6 14/81p 05/04/2011

8. Please confirm total number of shares in issue at the end of the period in order for us to update our records

5,198,436,308 as at 31 October 2012

Contact for Queries:

Name: Claire Spencer

Tel: 01753 494007

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: 01/05/2012 to 31/10/12

4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period

1,498,200 ORDINARY 6 14/81p

5. Number of shares issued/allotted under scheme during period

114,449 ORDINARY 6 14/81p

6. Balance under scheme not yet issued/allotted at end of period

1,383,751 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
1,000,000 ORDINARY 6 14/81p 15/04/2008
5,000,000 ORDINARY 6 14/81p 06/05/2009
2,500,000 ORDINARY 6 14/81p 17/10/2011

8. Please confirm total number of shares in issue at the end of the period in order for us to update our records

5,198,436,308 as at 31 October 2012

Contact for Queries:

Name: Claire Spencer

Tel: 01753 494007

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 Employee Share Purchase Plan

3. Period of return:

From: 01/05/2012 to 31/10/12

4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period

223,885 ORDINARY 6 14/81p

5. Number of shares issued/allotted under scheme during period

40,464 ORDINARY 6 14/81p

6. Balance under scheme not yet issued/allotted at end of period

183,421 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
100,000 ORDINARY 6 14/81p 15/04/2008
200,000 ORDINARY 6 14/81p 06/05/2009
200,000 ORDINARY 6 14/81p 05/04/2011

8. Please confirm total number of shares in issue at the end of the period in order for us to update our records

5,198,436,308 as at 31 October 2012

Contact for Queries:

Name: Claire Spencer

Tel: 01753 494007

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 Deferred and Matching Share Scheme

3. Period of return:

From: 01/05/2012 to 31/10/12

4. Number and class of shares(s) (amount of stock/debt security) not issued under scheme at end of last period

1,035,903 ORDINARY 6 14/81p

5. Number of shares issued/allotted under scheme during period

nil

6. Balance under scheme not yet issued/allotted at end of period

1,035,903 ORDINARY 6 14/81p

7. Number and class of share(s) (amount of stock/debt securities) originally listed and the date of admission

3,500,000 ORDINARY 6 14/81p 29/03/2010
3,500,000 ORDINARY 6 14/81p 05/04/2011
2,000,000 ORDINARY 6 14/81p 17/10/2011
2,000,000 ORDINARY 6 14/81p 14/03/2012

8. Please confirm total number of shares in issue at the end of the period in order for us to update our records

5,198,436,308 as at 31 October 2012

Contact for Queries:

Name: Claire Spencer
Tel: 01753 494007

Address: Centrica plc, Millstream, Maidenhead Road, Windsor, Berks SL4 5GD