Director/PDMR Shareholding

1

Details of the person discharging managerial responsibilities / person closely associated

a)

Name

Andrew Bonfield

2

Reason for the notification

a)

Position/status

Finance Director

b)

Initial notification /Amendment

Initial notification

3

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

National Grid plc

b)

LEI

8R95QZMKZLJX5Q2XR704

4

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transactions have been conducted

a)

Description of the financial instrument, type of instrument

Ordinary shares of 12 204/473p each

Identification code

GB00BDR05C01

b)

Nature of the transaction

Acquisition of securities in respect of the release of the 2014 Award under DSP.

c)

Price(s) and volume(s)

d)

Aggregated information

- Aggregated volume

- Price

e)

Date of the transaction

2017.06.19

f)

Place of the transaction

Outside a trading venue

4

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transactions have been conducted

a)

Description of the financial instrument, type of instrument

Identification code

Ordinary shares of 12 204/473p each

GB00BDR05C01

b)

Nature of the transaction

Shares sold in respect of statutory deductions in respect of the 2014 DSP release.

c)

Price(s) and volume(s)

d)

Aggregated information

- Aggregated volume

- Price

e)

Date of the transaction

2017.06.19

f)

Place of the transaction

London Stock Exchange (XLON)

Name of officer of issuer responsible for making notification: Robin Kerner.

Date of notification: 2017.06.21

1

Details of the person discharging managerial responsibilities / person closely associated

a)

Name

John Pettigrew

2

Reason for the notification

a)

Position/status

Chief Executive Officer

b)

Initial notification /Amendment

Initial notification

3

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

National Grid plc

b)

LEI

8R95QZMKZLJX5Q2XR704

4

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transactions have been conducted

a)

Description of the financial instrument, type of instrument

Identification code

Ordinary shares of 12 204/473p each

GB00BDR05C01

b)

Nature of the transaction

Acquision of securities in respect of the release of the 2014 Award under DSP.

c)

Price(s) and volume(s)

d)

Aggregated information

- Aggregated volume

- Price

e)

Date of the transaction

2017.06.19

f)

Place of the transaction

Outside a trading venue

4

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transactions have been conducted

a)

Description of the financial instrument, type of instrument

Identification code

Ordinary shares of 12 204/473p each

GB00BDR05C01

b)

Nature of the transaction

Shares sold in respect of statutory deductions in respect of the 2014 DSP release.

c)

Price(s) and volume(s)

d)

Aggregated information

- Aggregated volume

- Price

e)

Date of the transaction

2017.06.19

f)

Place of the transaction

London Stock Exchange (XLON)

Name of officer of issuer responsible for making notification: Robin Kerner.

Date of notification: 2017.06.21

1

Details of the person discharging managerial responsibilities / person closely associated

a)

Name

Mike Westcott

2

Reason for the notification

a)

Position/status

Group HR Director

b)

Initial notification /Amendment

Initial notification

3

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

National Grid plc

b)

LEI

8R95QZMKZLJX5Q2XR704

4

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transactions have been conducted

a)

Description of the financial instrument, type of instrument

Identification code

Ordinary shares of 12 204/473p each

GB00BDR05C01

b)

Nature of the transaction

Acquisition of securities in respect of the release of the 2014 Award under DSP.

c)

Price(s) and volume(s)

d)

Aggregated information

- Aggregated volume

- Price

e)

Date of the transaction

2017.06.19

f)

Place of the transaction

Outside a trading venue

4

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transactions have been conducted

a)

Description of the financial instrument, type of instrument

Identification code

Ordinary shares of 12 204/473p each

GB00BDR05C01

b)

Nature of the transaction

Shares sold in respect of statutory deductions in respect of the 2014 DSP release.

c)

Price(s) and volume(s)

d)

Aggregated information

- Aggregated volume

- Price

e)

Date of the transaction

2017.06.19

f)

Place of the transaction

London Stock Exchange (XLON)

Name of officer of issuer responsible for making notification: Robin Kerner.

Date of notification: 2017.06.21

1

Details of the person discharging managerial responsibilities / person closely associated

a)

Name

Alison Kay

2

Reason for the notification

a)

Position/status

Group General Counsel & Company Secretary

b)

Initial notification /Amendment

Initial notification

3

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

National Grid plc

b)

LEI

8R95QZMKZLJX5Q2XR704

4

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transactions have been conducted

a)

Description of the financial instrument, type of instrument

Identification code

Ordinary shares of 12 204/473p each

GB00BDR05C01

b)

Nature of the transaction

Acquisition of securities in respect of the release of the 2014 Award under DSP.

c)

Price(s) and volume(s)

d)

Aggregated information

- Aggregated volume

- Price

e)

Date of the transaction

2017.06.19

f)

Place of the transaction

Outside a trading venue

4

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transactions have been conducted

a)

Description of the financial instrument, type of instrument

Identification code

Ordinary shares of 12 204/473p each

GB00BDR05C01

b)

Nature of the transaction

Shares sold in respect of statutory deductions in respect of the 2014 DSP release.

c)

Price(s) and volume(s)

d)

Aggregated information

- Aggregated volume

- Price

e)

Date of the transaction

2017.06.19

f)

Place of the transaction

London Stock Exchange (XLON)

Name of officer of issuer responsible for making notification: Robin Kerner.

Date of notification: 2017.06.21

1

Details of the person discharging managerial responsibilities / person closely associated

a)

Name

George Mayhew

2

Reason for the notification

a)

Position/status

Corporate Affairs Director

b)

Initial notification /Amendment

Initial notification

3

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

National Grid plc

b)

LEI

8R95QZMKZLJX5Q2XR704

4

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transactions have been conducted

a)

Description of the financial instrument, type of instrument

Identification code

Ordinary shares of 12 204/473p each

GB00BDR05C01

b)

Nature of the transaction

Acquisition of securities in respect of the release of the 2014 Award under DSP.

c)

Price(s) and volume(s)

d)

Aggregated information

- Aggregated volume

- Price

e)

Date of the transaction

2017.06.19

f)

Place of the transaction

Outside a trading venue

4

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transactions have been conducted

a)

Description of the financial instrument, type of instrument

Identification code

Ordinary shares of 12 204/473p each

GB00BDR05C01

b)

Nature of the transaction

Shares sold in respect of statutory deductions in respect of the 2014 DSP release.

c)

Price(s) and volume(s)

d)

Aggregated information

- Aggregated volume

- Price

e)

Date of the transaction

2017.06.19

f)

Place of the transaction

London Stock Exchange (XLON)

Name of officer of issuer responsible for making notification: Robin Kerner.

Date of notification: 2017.06.21