Notification of Directors' Interests

National Grid plc ('National Grid')

Friday 2nd March 2012

Notification of Directors' Interests

Earlier today, the investment manager of the Chairman, Sir Peter Gershon's, personal pension scheme, purchased a further 10,000 shares at 647.39p per share, increasing his total interest to 18,055 National Grid plc ordinary shares.

Also today, two further Non-Executive Directors purchased holdings in the Company:

- Paul Golby purchased 2,500 shares at 648.918p per share.

- Ruth Kelly purchased 800 shares at 649.418p per share.

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Contact: D C Forward, Assistant Secretary

0207 004 3226