Blocklisting Interim Review

National Grid PLC
11 February 2008



National Grid plc ('NG')

11 February 2008

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

Block Listing Six Monthly Return

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

NB: References are to NG Ordinary shares of 1117/43p.

1. Name of Company                                      National Grid plc

2. Name of Scheme                                       Employee Shareschemes

3. Period                                               1 August 2007 to 31 January 2008

4. Shares not issued at end of last period:             1,350,512

5. Shares issued/allotted during period:                Nil

6. Balance not yet issued/allotted at end of period:    1,350,512

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 1117/43
                                                        pence were in issue.  See Note below:



Note: On 28 September 2007 a total of 3,705,193 newly listed ordinary shares
were allotted on conversion of all remaining National Grid plc 'B shares' in
issue to ordinary shares. The company's share repurchase programme continued
throughout the period, latterly concentrating on purchases of shares into
treasury as previously notified. Sharescheme operations were satisfied by
transfer of treasury shares; accordingly no further blocklisted shares were
allotted. Total number of shares in issue at end of the period: 2,581,913,516.
The balance of Treasury shares held at 31 January 2008 was 46,151,734, with
resulting voting share capital at close of 31 January 2008 at 2,535,761,782.

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

Contact: D C Forward, Assistant Secretary
Tel: [phone]

National Grid plc ('NG')
11th February 2008

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

Block Listing Six Monthly Return

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

NB: References are to NG Ordinary shares of 1117/43p.

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 2007 to 31 January 2008.

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.  See Note below:

Note: On 28 September 2007 a total of 3,705,193 newly listed ordinary shares
were allotted on conversion of all remaining National Grid plc 'B shares' in
issue to ordinary shares. No shares were utilised in respect of the above
Exchangeable Bonds during the reporting period. Total number of shares in issue
at end of the period: 2,581,913,516. The balance of Treasury shares held at 31
January 2008 was 46,151,734, with resulting voting share capital at close of 31
January 2008 at 2,535,761,782.

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

Contact: D C Forward, Assistant Secretary

Tel: [phone]


                      This information is provided by RNS
            The company news service from the London Stock Exchange