European Roadshow

June / July 2008

2

Cautionary statement

Unless otherwise stated, all financial data of National Grid contained in this presentation is as reported under IFRS. This presentation contains certain

statements that are neither reported financial results nor other historical information. These statements are forward-looking statements within the meaning of

Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. These statements include

information with respect to National Grid’s financial condition, National Grid’s results of operations and businesses, strategy, plans and objectives. Words such

as “anticipates”, “expects”, “intends”, “plans”, “believes”, “seeks”, “estimates”, “may”, “will”, “continue”, “project” and similar expressions, as well as statements

in the future tense, identify forward-looking statements. These forward-looking statements are not guarantees of National Grid’s future performance and are

subject to assumptions, risks and uncertainties that could cause actual future results to differ materially from those expressed in or implied by such forward-

looking statements. Many of these assumptions, risks and uncertainties relate to factors that are beyond National Grid’s ability to control or estimate precisely,

such as delays in obtaining, or adverse conditions contained in, regulatory approvals and contractual consents, unseasonable weather affecting the demand for

electricity and gas, competition and industry restructuring, changes in economic conditions, currency fluctuations, changes in interest and tax rates, changes in

energy market prices, changes in historical weather patterns, changes in laws, regulations or regulatory policies, developments in legal or public policy

doctrines, the impact of changes to accounting standards and technological developments. Other factors that could cause actual results to differ materially from

those described in this presentation include the ability to integrate the businesses relating to announced or recently completed acquisitions with National Grid’s

existing business to realise the expected synergies from such integration, the availability of new acquisition opportunities and the timing and success of future

acquisition opportunities, the timing and success or other impact of the sales of National Grid’s non-core businesses, the failure for any reason to achieve

reductions in costs or to achieve operational efficiencies, the failure to retain key management, the behaviour of UK electricity market participants on system

balancing, the timing of amendments in prices to shippers in the UK gas market, the performance of National Grid’s pension schemes and the regulatory

treatment of pension costs, and any adverse consequences arising from outages on or otherwise affecting energy networks, including gas pipelines owned or

operated by National Grid. For a more detailed description of some of these assumptions, risks and uncertainties, together with any other risk factors, please

see National Grid’s filings with and submissions to the US Securities and Exchange Commission (the “SEC”) (and in particular the "Risk Factors" and

"Operating and Financial Review" sections in its most recent Annual Report on Form 20-F). Except as may be required by law or regulation, National Grid

undertakes no obligation to update any of its forward-looking statements. The effects of these factors are difficult to predict. New factors emerge from time to

time and National Grid cannot assess the potential impact of any such factor on its activities or the extent to which any factor, or combination of factors, may

cause results to differ materially from those contained in any forward-looking statement.

3

National Grid…… a leading international electricity and gas company

Overview

� Owner/operator of gas/electricity networks in UK/US

� UK - Largest utility i

� US - 2nd largest utility ii

� 95% of our activities* are regulated� Predictable revenues and cashflows

� Remainder under long term contracts

� Market cap - c. £18bn

� Regulated RAV + Rate Base** - c. £25bn

� Other businesses

� Isle of Grain, Metering, BritNed, Property

ii By reference to customer numbers

i By reference to market capitalisation

Electricity T&D

$4 trillion

* By operating profit

** National Grid estimates for 31 March 2008. Excludes stranded costs

£17.2bn

UK regulated asset base**

7% upstate NY

gas distribution

$15.2bn

23% upstate

NY electricity distribution

4% Long

Island

generation

19% New England

electricity transmission & distribution

20% New England gas distribution

27% downstate NY gas

distribution

US regulated asset base**

38% gas

distribution38% electricity

transmission

24% gas

transmission

4

National Grid…… facts and figures on the Group (IFRS)

Operating profit (£bn)*

0.0

1.0

2.0

2004/05 2005/06 2006/07 2007/08

Earnings per share (p)*

0

20

40

2004/05 2005/06 2006/07 2007/08

Revenue (£bn)*

0.0

4.0

8.0

12.0

2004/05 2005/06 2006/07 2007/08

* Measured on a business performance basis, excluding US stranded cost recoveries. Business performance results are the primary financial performance measure used by National Grid, being the results for continuing operations before exceptional items and remeasurements. Remeasurements are movements in the carrying value of financial instruments and of commodity

contracts that arise from changes in mark-to-market values or in exchange rates and are reflected in the income statement to the extent that hedge accounting is not achieved or is not fully

effective.

1 Gross debt defined as net debt plus cash and cash equivalents and investments

Gross External Debt1 at March 31 2008 (£m)IFRS

National Grid plc and NGG Finance plc 5,277

National Grid Electricity Transmission plc 3,864

National Grid Gas plc 6,0332

National Grid Grain LNG 288

Total UK gross external debt 15,462

Total US (£1=$1.9845) 4,451

Other (3)

Total IFRS gross external debt 19,910

Less Cash and Investments (2,269)

Net debt 17,641

2 Measured as the contribution to the consolidated Group accounts

(£m)IFRS

+28%

+25%

5

Evolution of the Group

Niagara Mohawk

NEES / EUA

Lattice

Crown Castle UK

National GridGroup

National GridGroup

KeySpan

Rhode Islandgas distribution

National GridCompany

National GridTransco

British Gas

Demergers:Centrica and BG

c. $2.0bn EV

Sale of 4 UK gas

distribution networks

c. £5.8bn ($11.6bn) proceedsEV c. $575m

EV c.$11.8bn

c. $8.2bn EV

c. $5.1bn EVEV = Enterprise Value = total of cash &

equity purchase/sale price + acquired/sold debt

FX rate used for conversion = GBP/USD 2.0

Sale of wireless and

Basslink assets

Sale of Ravenswood Generation

c. £3.2bn ($6.4bn) proceeds

c. $2.9bn expected proceeds

6

National Grid…… multiple regulated utility businesses in our corporate structure

National Grid plcBaa1 / BBB+ / BBB+

National Grid Holdings One plcNR / BBB+ / NR

NGG Finance plcNational Grid USA

A3 / BBB+ / NR

Niagara Mohawk Power Corp A3 / BBB+ / NR

Lattice Group plc

National Grid Grain LNGNational Grid PropertyMetering (unregulated)

National Grid Gas plcA3 / A- / A

National Grid Gas Holdings plc

A3 / BBB+ / A

NGUSA Other businesses

National GridHoldings Ltd

National Grid ElectricityTransmission plc

A3 / A- / A

Guarantee over bonds

National Grid Commercial Holdings

Ltd

British Transco Capital IncBritish Transco International

Finance BVBritish Transco Finance Inc

Massachusetts Electric A3 / A- / NR

New England Power A3 / A- / NR

Granite State Electric

Nantucket Electric

Narragansett ElectricA3 / A- / NR

KeySpan CorpBaa1 / A- / A-

KeySpan Gas East Corp A3 / A / A

National Grid NEHoldings 2 LLC

The Brooklyn Union Gas Company

NR / A / A+

Colonial Gas Co A3 / A- / NRBoston Gas Co. Baa1 / A- / NREssex Gas Co.EnergyNorth Natural Gas Inc

National Grid Generation LLC Baa1/ A- /NR

KeySpan Other businesses

KeySpan Energy Corporation

Other

KeySpan Ravenswood

Guarantee over preference shares

7

What our core businesses do…

… Transmission

Note: In the US National Grid has 20.4% interest in Iroquois Gas Transmission System and 26.5% interest in Millennium Pipeline NY

c.7,400 km of high pressure gas pipeline; c.7,200 circuit kilometres of high-voltage overhead line; c.675 km of underground electricity cable

c.13,800 km of electricity transmission network; 224 km direct current transmission line

8

What our core businesses do…… Gas distribution

c.132,000 km of distribution pipelines; Distributes gas on

behalf of gas shippers and suppliers to 10.8m consumers

Around 3.5 million customers; nearly 58,000 km of main and distribution pipe

9

What our core businesses do…… Electricity distribution and generation

3.4 million electricity customers; Distribution network of 116,000 circuit kilometres; 4,119 MW of generation capacity (excluding Ravenswood which is to be sold)

10

Non-regulated businesses

National Grid’s non-regulated businesses and other operations are located in the UK and either operate in the market related to those of its principal businesses or provide support to its businesses.

Key facts

� National Grid Metering and Onstream provide metering and meter reading services for over 20 million domestic, industrial and commercial meters on behalf of gas and electricity suppliers

� Grain LNG - National Grid’s liquefied natural gas facility at the isle of Grain is the first new LNG import terminal in the UK for30 years. Operating since July 2005, Grain LNG is a world-class facility providing a vital link between the UK, European gas markets and global LNG sources.

� National Grid Property is responsible for managing all our major occupied properties in the UK, and for the management, clean up and disposal of surplus properties, largely comprising contaminated former gas works.

� Fulcrum Connections is the largest provider of gas connections and associated design services with a national footprint in the UK.

UK Property

11

Regulatory overview

� In the US, for regulatory purposes, we maintain several separatePublic Utility Companies, a number of which have more than one rate plan

� Electric transmission

� Electric distribution

� Gas distribution

� Generation

� In the UK, services are provided through 2 separate regulated entities with distinct price controls

� Electric transmission

� Gas transmission

� Gas distribution

12

Regulatory process…

… many common elements to rate agreements in UK and US

� Return on asset base

� Opex allowance

� Pensions and tax allowance

� No commodity exposure

� Incentive mechanisms

� Some residual volume drivers

� Protection from uncontrollable costs

� Varied approaches to capex

� No volume exposure

� Indexation

� Capex revenue drivers

13

Valuing our regulated businesses…

… main value drivers same

� Asset replacement

� Load related investment

� Local cost of capital

� Investment efficiencies

� Global operating model

� Global IS & Shared Services

Growth in asset / rate base

Financial outperformance

Operating outperformance

SAME VALUE DRIVERS

14

Valuing our regulated businesses…… forecast asset base growth over 35% in UK & over 25% in US

2006/07 2011/12 2006/07 2011/12

£19.2bn

£14bn

$14.3bn*$18.2bn

*Excludes US stranded costs ($1.7bn)

UK - opening 2006/07 RAV. US - average rate base for 2006 calendar year

15

Regulatory settlements…

… staggered rate plans provide further stability

2007 2008 2009 2010 2011 2012 2013 2014

Transmission (2)

Gas Distribution (4)

NiMo (electric)

NiMo (gas)

Brooklyn Union Gas

KeySpan Gas East

MECO

Boston Gas

Essex Gas

Colonial Gas

Narrangansett (elec.)

Narragansett (gas)

GSE

Energy North

LI Generation

NEP Formula transmission rates

Rate case in progress

Rate case in progress

Rate case in progress

FE

RC

NH

Rh

od

e

Isla

nd

Ma

ssa

-c

hu

se

tts

New

Yo

rkO

fge

m

to 2019

to 2019

16

Investment…... capital expenditure in regulated businesses and infrastructure projects has increased over the past 3 years

£ billion

0

5

10

15

2006 - 2012

Expected balance to 2012

Expected in 2008/09

Delivered in 2007/08

Delivered in 2006/07

~£7.5bn

~£3.0bn

£3.1bn

£2.3bn

Drivers of capital expenditure to 2012 and beyond

WindWind

NuclearNuclear

Thermal generationThermal generation

Other renewablesOther renewables

More inter-connectionMore inter-connection

‘Smart grids’‘Smart grids’

Smart meteringSmart metering

Changing demand patternsChanging demand patterns

Continued asset replacementContinued asset replacement

More network connections

More network connections

New technologyNew technology

Increased

investment

in networksfor the

future

Increased

investment

in networksfor the

future

17

Funding the Group…... debt maturities and regulated investment drive issuance

Net debt is expected to rise from £17.6bn at 31st March 2008 to c.£19bn at March 2009 and £22bn - £23bn at March 2012.

Maturities of c. £6bn to March 2012.

The Group has raised c. £1bn since 31st March 2008.

Outstanding requirement for net new funding of approximately £4bn by 31st March 2012.

Around £1.5bn is required by March 2009 from a combination of bank loans, commercial paper and bond issuance.

Possible issuance from UK OpCos, NG plc and the NGUSA Group.

0

500

1,000

1,500

2,000

2,500

08/0

9

09/1

010/1

1

11/1

212/1

3

13/1

414/1

515/1

6

16/1

717/1

8

18/1

919/2

0

20/2

121/2

2

22/2

323/2

4

24/2

525/2

6

26/2

727/2

828/2

9

29/3

030/3

1

31/3

232/3

3

33/3

434/3

5

35/3

636/3

7

37/3

838/3

9

39/4

040/4

141/4

2

43/4

446/4

7

48/4

952/5

3

56/5

7

Maturity

£ equiv

. (m

)

National Grid Grain LNG

National Grid USA Group

National Grid / NGGF

National Grid Electricity Transmission

National Grid Gas Group

National Grid Group Long Term Debt Maturity Profile as at 15 May 2008

18

Funding the Group…… liquidity

Minimal impact from the credit crunch

� spreads to LIBOR have risen but rates have fallen

� Commercial Paper markets have remained open to National Grid throughout

� c. £2.9bn of undrawn committed borrowing facilities

Limited exposure to institutions impacted by the credit crunch

� no direct exposure to US subprime mortgage market

� cash balances spread between institutions

� principally AAA-rated Money Funds

� credit exposure to all institutions managed and monitored according to credit rating

19

Group borrowing facilities and liquidity as at 15th May 2008

� $1.5bn 364-day undrawn syndicated loan facility with 12-month term out; terminates 12th November 2008 with no MAC event of default or ratings related covenants. National Grid USA is a named borrower

� Short-term funding programmes:

� USCP $3bn: Nil outstanding

� ECP $1.5bn: Nil outstanding

� €15bn EMTN programme (joint with NGET):

� National Grid in issue €6.4bn; NGET €2.7bn

� €5.9bn unissued

� $355m NGUSA syndicated loan facility (5-year Revolving Credit Facility). Expires November 2009

� $325m NGUSA syndicated loan facility (5-year Standby Bond Purchase Facility). Expires November 2009

� $2bn NGUSA commercial paper programme: c.$500m outstanding

� €4bn NGUSA EMTN programme: €99m issued

� $1.5bn undrawn KeySpan Corporation syndicated loan facility maturing June 2009 ($580m) and June 2010 ($920m)

� $1.5bn KeySpan Corporation US commercial paper programme: c.$200m outstanding

� £810m undrawn committed bank lines – 5 year duration; minimal covenants. Expires December 2010

� Short-term funding programmes:

� USCP $2.5bn: Nil outstanding

� ECP $1.25bn: Nil outstanding

� €10bn EMTN programme: €4.2bn unissued

� £425m undrawn committed bank lines – 5 year duration, minimal covenants. Expires December 2010

� Short-term funding programmes:

� USCP $1bn: Nil outstanding

� ECP $1bn: Nil outstanding

National Grid plc

National Grid USA Group

National Grid Gas plc

National Grid Electricity Transmission plc

20

Predictability of regulated cash flows is a key factor in our ratings…… Group credit ratings

The ratings set forth above are not a recommendation to purchase, hold or sell National Grid’s notes, that may be issued from time to time, inasmuch as the ratings do not comment as to market price or suitability for a particular investor. The ratings are based on current information we have furnished to the rating agencies and information obtained by the rating agencies from othersources. The ratings are only accurate as of the date hereof and may be changed, superseded or withdrawn as a result of changes in, or unavailability of, such information and, therefore, a prospective purchaser should check the current ratings before purchasing National Grid’s notes.

A/---A/---A3/---KeySpan Gas East Corporation

A+/---A/---Not ratedThe Brooklyn Union Gas Company

A-/---A-/A2Baa1/P2KeySpan Corporation

Not ratedA-/--Baa1/--Boston Gas Company

Not ratedA-3/---A3/---Colonial Gas Company

Not ratedA-3/A2A32/---The Narragansett Electric Co.

Not ratedBBB+/A2A3/--Niagara Mohawk Power Corporation

Not ratedBBB+/A2A3/P2National Grid USA

Not ratedA-/A2A3/P2New England Power Co.

Not ratedA-/A2A3/P2Massachusetts Electric Co.

1Moody’s ratings placed on Negative Outlook on 31st January 2008 2 Issuer rating 3 Corporate credit rating

Not ratedA-3/---Baa1/---National Grid Generation LLC

A/---BBB+/---A3/---National Grid Gas Holdings plc

A/F2A-/A2A3/P2National Grid Gas plc

Not ratedBBB+/A2Not ratedNational Grid Holdings One plc

A/F2A-/A2A3/P2National Grid Electricity Transmission plc

BBB+/F2BBB+/A2Baa1/P2National Grid plc

FitchS&PMoody’s1Senior Unsecured / Short-Term ratings

21

2008/09 financing metric

Interest cover

� Reflects the calculation used by our credit rating agencies

� 3.2x for the year

� Aim to manage within a range of 3.0 – 3.5x

2.50

2.75

3.00

3.25

3.50

3.75

4.00

2005/06 2006/07 2007/08

2.50

2.75

3.00

3.25

3.50

3.75

4.00

Target range Interest cover

22

National Grid…… what to look out for

� Sale of Ravenswood

� US gas rate plan agreements

� Deliver KeySpan integration and update on synergies against target

� Continue to implement global operating model

� Dialogue with NYPSC over additional New York investment

� Deliver capital investment plans and Rate Base growth

� Potential debt issuance opportunities in the NGUSA Group

Continued commitment to A range ratings at UK OpCos

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Treasury Contacts

Malcolm Cooper (Group Tax and Treasury Director):

D: +44 (0)20 7004 3340 malcolm.cooper@ngrid.com

Andrew Kluth (Assistant Treasurer, Funding):

D: +44 (0)20 7004 3365 andrew.kluth@ngrid.com

Andy Mead (Manager, Corporate Banking):

D: +44 (0)20 7004 3369 andy.mead@ngrid.com

David Bonar (Manager, Structured Finance):

D: +44 (0)20 7004 3368 david.bonar@ngrid.com

David Morgan (Assistant Manager, Corporate Banking):

D: +44 (0)20 7004 3379 david.morgan@ngrid.com

Group Website: www.nationalgrid.com

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