July 21, 2006

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                            SCHEDULE 14A INFORMATION

                  Proxy Statement Pursuant to Section 14(a) of
            the Securities and Exchange Act of 1934 (Amendment No. )

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[ ]     Definitive Proxy Statement
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[ ]     Soliciting Material Pursuant to Section 240.14a-12

                              KeySpan Corporation
                              -------------------
                (Name of Registrant as Specified in Its Charter)

                                     (N/A)
                                     -----
    (Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

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Attached  is a copy of a press  release  issued  by  National  Grid and  KeySpan
Corporation.

NATIONAL GRID                                                KEYSPAN CORPORATION

            NATIONAL GRID - KEYSPAN MERGER PROVIDES CUSTOMER SAVINGS
                             AND CREATES A PLATFORM
                     TO HELP CUSTOMERS CONTROL ENERGY COSTS
      Programs on energy efficiency, low-income assistance, supplier choice


Brooklyn, NY and Westborough, MA (July 21) - In a filing with the New York State
Public Service  Commission,  KeySpan Corp.  (NYSE:  KSE) and National Grid (LSE:
NG.L NYSE:  NGG),  proposed a plan under which the merged companies will provide
customer  savings and will be better  positioned to serve customers by operating
efficiently,  managing energy supply costs and expanding programs to help reduce
energy use.  Additional  benefits coming to KeySpan customers include low-income
and supplier choice programs, and accelerated infrastructure improvements.

"National  Grid and KeySpan are  delivering  on our promise to bring savings and
additional  benefits to customers in New York and on Long  Island," said Michael
E. Jesanis,  chief executive  officer of National Grid USA. "Our plan will allow
us to better meet customers' needs,  operate more efficiently,  and provide safe
and reliable service through investments in the energy infrastructure."

The merged  companies  will  provide  benefits to  customers  by reducing  costs
through  combining  resources and by more  comprehensively  managing a large gas
supply  portfolio.  National  Grid will also  expand its  proven  menu of energy
efficiency programs to KeySpan customers to help them cope with energy costs.

The proposal,  filed yesterday,  calls for National Grid resources and expertise
to complement KeySpan's existing strengths.

"It is only through our acquisition by National Grid,  forming the third largest
gas delivery company in the nation, that we are able to provide these additional
benefits to our customers," said Robert B. Catell,  chairman and chief executive
officer of KeySpan.  "Through  our  innovative  plan,  we are able to reduce the
costs to our  customers  and are even better  equipped  to  surmount  the energy
challenges of the future."

Permanent  customer  savings of more than $500  million  anticipated  during the
10-year proposal,  possible through the cost-reductions generated from combining
the companies, include:

o    $131 million in savings to Long Island  energy gas  customers  comprised of
     $64 million in business operations efficiency and $67 million in gas supply
     management savings. Additional savings will be available to the 1.1 million
     electric  customers  of the Long Island  Power  Authority in the event LIPA
     ultimately approves the transfer of its existing  contractual  arrangements
     from KeySpan to National Grid.


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o    $173  million  to KeySpan  customers  in New York City  (Brooklyn,  Queens,
     Staten Island) including $109 million in business operations efficiency and
     $64 million in gas supply management savings

o    $218 million to National Grid customers in upstate New York (former Niagara
     Mohawk  service  territory),  including more than $14 million in gas supply
     management savings

These  reductions  in costs  will be used to  reduce  necessary  rate  increases
primarily due to hikes in property taxes, the cost of environmental  clean-up of
existing brownfield sites and increased pension costs.

Catell said that KeySpan customers have not experienced a delivery rate increase
in 10 years,  made  possible  through the  company's  growth and  previous  cost
reductions.

"KeySpan has been experiencing  dramatic increases in these areas outside of our
control  and was  preparing  to file a new rate  plan  when the  opportunity  to
produce costs savings through a merger with National Grid emerged," Catell said.
"Through the  efficiencies  of combining with National Grid, the customer impact
of these familiar rising costs will be reduced."

Instead of the  potential  for an  immediate  KeySpan rate  increase  request of
approximately  10 percent without a merger with National Grid,  today's proposal
provides  for no  delivery  rate  increases  for 18 months,  followed  by modest
increases spread out over the 10-year rate plan. On average,  from 2007 to 2017,
the rate plan is  expected to result in an  estimated  increase of only 1 to 1.5
percent on annual customer bills,  which is approximately  one-half the expected
rate of  inflation.  A typical  residential  customer in Brooklyn,  for example,
would experience an estimated $25 to $37.50 annual increase on an average yearly
bill of $2,500.  The price  customers  pay for actual  natural gas supplies will
continue to  fluctuate  with market  conditions  and be passed  through  without
markup.

Although  some job  consolidations  are necessary to achieve cost savings in the
proposal,  National  Grid and  KeySpan  expect to achieve  any staff  reductions
through attrition and voluntary programs. No layoffs are expected.

Also included in the proposal are plans that will further benefit customers:

o    Improved  opportunities for customers to choose their natural gas supplier.
     The proposal calls for new efforts to encourage  additional  supply choices
     for KeySpan customers. Features of a recently approved alternative supplier
     referral  program for National  Grid  customers in upstate New York will be
     expanded to KeySpan customers.


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o    Continuation of KeySpan  comprehensive safety and service quality incentive
     programs.

o    Acceleration of a bare steel pipe  replacement  program,  boosting  current
     plans by an  additional  20 miles a year in Long Island.  The  replacements
     enhance the ability to provide customers with safe, reliable service.

o    Discounts  will be  available  for up to  90,000  of  KeySpan's  customers.
     Discounts to qualifying low-income customers will increase to $7.50 a month
     for heating and to $3.50 a month for non-heating customers.

Beyond  today's  filing,   the  merger  is  expected  to  generate   significant
environmental  benefits to Long Island,  consistent  with National Grid's global
reputation as a leader in sustainable business.

In 2005  National  Grid topped the Pacific  Sustainability  Index,  a ranking of
environmental  and social  disclosure  and  performance  by energy  and  utility
companies  listed on the Fortune  Global 500.  National Grid is also included on
the Dow Jones  Sustainability  World  Index  and the  FTSE4Good,  indices  whose
memberships  include  companies with high standards of environmental  and social
performance.  National  Grid has been  honored  by the New York  Chapter  of the
League of  Conservation  Voters and the National  Arbor Day  Foundation  for its
business  practices.  For six  consecutive  years through 2005 National Grid has
received  the U.S.  Environmental  Protection  Agency and  Department  of Energy
National ENERGY STAR Award for its appliance and lighting program.

National Grid also repeated its commitment to the communities KeySpan serves.

"National Grid will maintain KeySpan's  long-standing  commitment to its service
territory,"  Jesanis said.  "Our business is inherently  local,  with  employees
living and working  throughout the territory we serve.  We are also committed to
maintaining historic levels of charitable giving and community investment."

The  merger  rate  proposal  is subject to review by staff of the New York State
Department  of  Public  Service  and  approval  by the New York  Public  Service
Commission.

Today's filing is another step in the process of gaining regulatory approval for
the  transaction.  In May,  National  Grid and KeySpan filed for approval of the
merger from the U.S. Federal Energy  Regulatory  Commission.  Earlier this month
the  transaction  gained  clearance  on its filings in  compliance  with federal
antitrust and foreign investment  requirements.  A filing with the New Hampshire
Public Utilities Commission is expected in the coming weeks.


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About National Grid:
- --------------------

National  Grid is an  international  energy  delivery  business  with  principal
activities in the regulated electricity and natural gas industries. In the U.S.,
National Grid transmits and distributes  electricity and natural gas to nearly 4
million  customers across 29,000 square miles of  Massachusetts,  New Hampshire,
New York and Rhode Island.

KeySpan  will be  National  Grid's  fifth  US  acquisition.  Previously,  it had
acquired New England Electric System and Eastern  Utilities  Associates  (2000),
and Niagara  Mohawk (2002).  Earlier this year,  National Grid announced that it
will  acquire the Rhode  Island gas  distribution  business  of  Southern  Union
Company.

The company owns the high-voltage  electricity  transmission  network in England
and Wales  and  operates  the  system  across  Great  Britain.  It also owns and
operates the high-pressure  gas transmission  system in Britain and, through its
natural gas  distribution  business  serves over 11 million  meters in homes and
businesses in Britain. In addition,  it has a number of businesses  operating in
related areas such as LNG importation, wireless infrastructure for broadcast and
telecommunications,   property,   metering   and   interconnectors.   For   more
information, visit National Grid's web site at www.nationalgrid.com.

About KeySpan:
- --------------

A member of the Standard & Poor's 500 Index,  KeySpan Corporation  (NYSE:KSE) is
the fifth  largest  distributor  of  natural  gas in the  United  States and the
largest  in the  Northeast,  operating  regulated  gas  utilities  in New  York,
Massachusetts  and  New  Hampshire  that  serve  2.6  million  customers.  These
customer-focused businesses are complemented by a portfolio of service companies
that  offer  energy-related  products,  services,  and  solutions  to homes  and
businesses.  KeySpan is also the largest  electric  generator in New York State,
with approximately 6,650 megawatts of generating capacity that provides power to
1.1 million  customers of the Long Island Power Authority  (LIPA) on Long Island
and supplies approximately 25 percent of New York City's capacity needs. KeySpan
also operates  LIPA's  transmission  and  distribution  system under contract to
LIPA. In addition to these assets, KeySpan has strategic investments in pipeline
transportation,  distribution, storage, and production. KeySpan has headquarters
in Brooklyn, New England, and Long Island. For more information, visit KeySpan's
web site at www.keyspanenergy.com.


Media Contacts:

National Grid
Alberto Bianchetti
315-428-6932

KeySpan
718-403-2503
24-hour pager: 516-824-1241


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Additional Information and Where to Find It
- -------------------------------------------

In connection with the proposed merger, the Company has filed a definitive proxy
statement with the Securities and Exchange Commission.  BEFORE MAKING ANY VOTING
OR  INVESTMENT  DECISION,  THE  COMPANY  STOCKHOLDERS  ARE  URGED  TO  READ  THE
DEFINITIVE PROXY STATEMENT BECAUSE IT CONTAINS  IMPORTANT  INFORMATION ABOUT THE
PROPOSED MERGER. The definitive proxy statement is also available free of charge
at  the  Securities  and  Exchange   Commission's  website,   www.sec.gov,   and
stockholders  of the  Company are also able to obtain  additional  copies of the
definitive proxy statement free of charge by directing their requests to KeySpan
Corporation One MetroTech Center, Brooklyn, New York 1120-3850.

The  Company  and its  directors  and  executive  officers  may be  deemed to be
participants in the  solicitation of proxies from its stockholders in connection
with the proposed merger.  Information concerning the interests of the Company's
participants in the  solicitation is set forth in the Company's proxy statements
and Annual  Reports  on Form 10-K,  previously  filed  with the  Securities  and
Exchange  Commission,  and in the  definitive  proxy  statement  relating to the
merger.












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