Publication of Prospectus

National Grid PLC
01 December 2006

Publication of Supplementary Prospectus

The following supplementary prospectus has been approved by the UK Listing
Authority and is available for viewing:

Supplementary Prospectus dated 1 December 2006

National Grid plc and National Grid Electricity Transmission plc
Euro 12,000,000,000
Euro Medium Term Note Programme

To view the full document, please paste the following URL into the address bar
of your browser.


http://www.rns-pdf.londonstockexchange.com/rns/1172n_-2006-12-1.pdf



For further information, please contact

Andrew Kluth 
Assistant Treasurer
National Grid plc 
1-3 Strand 
London WC2N 5EH

Tel:     [phone]
Fax:      [phone]

Clive Hawkins
Media Relations
National Grid plc 
1-3 Strand 
London WC2N 5EH

Tel:     [phone]
Fax:      [phone]


DISCLAIMER - INTENDED ADDRESSEES

Please note that the information contained in the Supplementary Prospectus may
be addressed to and/or targeted at persons who are residents of particular
countries (specified in the Prospectus for the National Grid plc / National Grid
Electricity Transmission plc Euro 12,000,000,000 Euro Medium Term Note Programme
dated 11 August 2006) only and is not intended for use and should not be relied
upon by any person outside these countries. Prior to relying on the information
contained in the Supplementary Prospectus you must ascertain from the Prospectus
whether or not you are part of the intended addressees of the information
contained therein. 

Your right to access this service is conditional upon complying with the above
requirement.  


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