London, June 23, 2026, 14:05 (BST)
National Grid plc shares fell 0.7% to 1,212.5 pence in Tuesday afternoon trading, despite the completion of a large transmission project in New York. The stock opened at 1,218 pence, against Monday’s close of 1,221 pence.
The decline was steeper than the FTSE 100’s 0.34% fall to 10,402.11. It left National Grid’s market value at about £60.3 billion.
The immediate company news was positive. New York officials said the 100-mile Smart Path Connect transmission line had entered service, unlocking one gigawatt of renewable-energy capacity and delivering an estimated $438 million in annual benefits for consumers. National Grid developed the project with the New York Power Authority.
That matters for shareholders because National Grid’s investment case rests on turning heavy spending into a larger base of regulated assets, on which utilities are permitted to earn returns. Smart Path Connect is a completed piece of that programme, rather than another project awaiting permits or construction.
National Grid built the 55-mile southern section between Croghan and Marcy, including a new substation. The wider scheme added four substations and upgraded 10 others. Sally Librera, president of National Grid New York, said the project delivers renewable power “directly to the businesses and communities that need it most.” Governor Kathy Hochul
It also feeds into National Grid’s Upstate Upgrade, a portfolio of more than 70 New York transmission projects scheduled through 2030. The work is intended to relieve congestion — the bottlenecks that prevent electricity from moving efficiently between regions — while preparing the network for rising demand.
The selling was not confined to National Grid. SSE, another capital-heavy British electricity network operator, dropped 1.2% to 2,319 pence. That pointed to broader pressure on utility valuations rather than a negative reading of the New York announcement alone.
London shares weakened as investors increased bets on higher interest rates. Markets were pricing about two quarter-percentage-point increases from the U.S. Federal Reserve before year-end and at least one such rise from the Bank of England in December. Higher rates tend to weigh on utilities by raising financing costs and making their dividends less attractive compared with bonds.
National Grid’s last annual results showed adjusted operating profit of £5.68 billion, slightly below the £5.75 billion analyst consensus. It also recorded £636 million of timing under-recoveries, meaning revenue permitted by regulators had not yet been collected from customers. The company retained its forecast for adjusted earnings per share to grow 13% to 15% in the year ending March 2027.
Chief Executive Zoë Yujnovich has called the company’s plan “the largest investment programme in our history”. National Grid expects to spend at least £70 billion over five years after investing a record £11.6 billion in the latest financial year. Underlying earnings reached 78 pence per share. Investegate
But that expansion carries risk. Net debt rose 7% to £44.2 billion and is expected to increase by slightly more than £6 billion this year as construction accelerates. A longer period of high interest rates, project delays or weaker-than-expected regulatory cost recovery could slow cash generation and put further pressure on the shares.
For now, the market is treating Smart Path Connect as evidence that National Grid can deliver major infrastructure, but not as a reason to ignore its funding burden. Rates, debt and the returns allowed by regulators remain the larger drivers of the stock.
