Blocklisting Interim Review

National Grid PLC
07 February 2007



National Grid plc ('NG')

7th February 2007

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Block Listing Six Monthly Return

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NB: References are to NG Ordinary shares of 11 17/43p.

1. Name of Company                                      National Grid plc

2. Name of Scheme                                       Employee Shareschemes

3. Period                                               1 August 2006 to 31 January 2007

4. Shares not issued at end of last period:             2,950,788

5. Shares issued/allotted during period:                2,463,171

6. Balance not yet issued/allotted at end of period:    487,617

7. No. of shares originally listed and date of          On 1 August 2005, following NG's capital consolidation,
admission:                                              a total of 2,712,727,627 New Ordinary Shares of 11 17/43
                                                        pence were in issue.



Total number of shares in issue at end of the period:  2,714,078,930 (following
the repurchase and cancellation of 9,198,381 shares in the period).

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Contact: D C Forward, Assistant Secretary

Tel: [phone]


National Grid plc ('NG')

7th February 2007

-----------------------------------------------------

Block Listing Six Monthly Return

-----------------------------------------------------

NB: References are to NG Ordinary shares of 11 17/43p.

1. Name of Company                                      National Grid plc

2. Name of Scheme                                       National Grid Electricity Transmission plc-

                                                        4.25 per cent Exchangeable Bonds 2008.
3. Period                                               1 August 2006 to 31 January 2007.

4. Shares not issued at end of last period:             37,388

5. Shares issued/allotted during period:                Nil

6. Balance not yet issued/allotted at end of period:    37,388

7. No. of shares originally listed and date of          On 1 August 2005, following NG's capital consolidation,
admission:                                              a total of 2,712,727,627 New Ordinary Shares of 11 17/43
                                                        pence were in issue.



Total number of shares in issue at end of the period: 2,714,078,930 (following
the repurchase and cancellation of 9,198,381 shares in the period).

-----------------------------------------------------------------

Contact: D C Forward, Assistant Secretary

Tel: [phone]


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