UK Long-Term Borrowing Costs Hit Highest Since 1998, Squeezing Healey's Budget Headroom

UK government bond yields surged on 1 September 2026 as a global bond sell-off, sparked by inflation fears tied to US-Iran tensions and heavy tech-sector borrowing, hit Britain hardest among G7 nations. The 30-year gilt yield touched 5.89%, its highest since 1998, while the 10-year yield reached 5.25%, the highest since the 2008 financial crisis. Economists estimate the higher debt-servicing costs have eroded Chancellor John Healey's fiscal headroom from the roughly £24-26 billion he inherited from Rachel Reeves at the March forecast to as little as £13.8-15 billion ahead of his first Budget on 28 October. Deutsche Bank's Sanjay Raja said 'getting the bond maths wrong at this juncture could risk a painful sell-off,' while Capital Economics' Ruth Gregory said Healey 'needs to cut government spending and/or raise taxes by something like £9-14bn.' Analysts warned a further £5bn hit from energy costs could push required consolidation even higher, intensifying pressure on Healey to raise taxes despite Labour's manifesto pledges.