Exhibit 99.1
SUMMARY
FORM6-K
SECURITIES AND EXCHANGE COMMISSION
Washington D.C. 20549
Report of Foreign Issuer
Pursuant to Rule 13a – 16 or 15d – 16 of
The Securities Exchange Act of 1934
Announcements sent to the London Stock Exchange
National Grid plc,1-3 Strand, London, WC2N 5EH, United Kingdom
Routine announcements in the period to 2 February 2018
| 02 February 2018 | Director/PDMR Shareholding | |
| 01 February 2018 | Total Voting Rights | |
| 16 January 2018 | Director/PDMR Shareholding | |
| 15 January 2018 | Transaction in own shares | |
| 12 January 2018 | Transaction in own shares | |
| 12 January 2018 | Director/PDMR Shareholding | |
| 11 January 2018 | Transaction in own shares | |
| 10 January 2018 | Transaction in own shares | |
| 09 January 2018 | Transaction in own shares | |
| 09 January 2018 | Director/PDMR Shareholding | |
| 08 January 2018 | Transaction in own shares | |
| 05 January 2018 | Transaction in own shares | |
| 04 January 2018 | Transaction in own shares | |
| 03 January 2018 | Transaction in own shares |
Note: During the period a ‘same day’ Form6-K was issued in respect of the following National Grid plc announcements:
09 January 2018: Scrip dividend
10 January 2018: Total Voting Rights
22 January 2018: Three-year rate plan proposed for Niagara Mohawk Electric & Gas
23 January 2018: National Grid responds to Ofgem’s Hinkley Consultation
02 February 2018: National Grid plc provides update on impact of US Tax Reform
