The latest 20-year loan is the largest secured by a UK distribution company from the EIB to date, and is in addition to £350 million already provided by the EIB to UKPN in December 2012.
UKPN is investing in its network across the East of England and South East to ensure continued reliable supply and to provide additional capacity for future demand.
Approximately 10,000 new connections are made every year to the network which distributes more than a quarter of the UK’s electricity.
UKPN chief executive Basil Scarsella said: “Since UK Power Networks was created in 2010 we have reduced the frequency of power cuts by a quarter and cut average duration by half.
“We believe long-term investment is essential to build on these achievements and deliver sustainable improvements for customers”.
The EIB’s vice-president Jonathan Taylor said: “We recognise the importance of ambitious investment being carried out by power companies across the country and this loan reflects the professional commitment of UKPN that will benefit their customers for years to come.”
The EIB has invested more than £10 billion in the UK energy sector including in national transmission networks and regional power distribution, and interconnectors to Ireland and mainland Europe.
Earlier this month fellow distribution company Northern Powergrid secured a £250 million investment over two years from the EIB to help fund a £3 billion eight-year upgrade programme of its energy network in the North East.