Britain sold £4.25 billion of 30-year gilts at a record 5.82% yield, the highest since 1998, as the Iran war oil surge cooled rate-cut bets and squeezed the fiscal headroom for Chancellor John Healey's October budget.
Britain sold £4.25 billion of 30-year gilts at a record 5.82% yield, the highest since 1998, as the Iran war oil surge cooled rate-cut bets and squeezed the fiscal headroom for Chancellor John Healey's October budget.

Britain locked in its costliest long-term borrowing in 28 years Tuesday, pricing £4.25 billion of 30-year gilts at 5.82%, the highest yield since the Debt Management Office's 1998 founding.
"Today's syndication shows demand for gilts at these yields remains in good health," said Matthew Amis, investment director at Aberdeen Investments. "A poorly received gilt syndication would have put further pressure on gilt yields and in turn government finances."
The 10-year gilt yield trades near 5.2%, the highest among the Group of Seven. France's 30-year yield reached 5.02%, its highest since September 2008, while Germany's climbed to 3.86%, the highest since 2011. Brent crude futures are approaching $100 a barrel after the U.S.-Iran war sent energy prices surging, reigniting inflation concerns and sharply reducing expectations for rate cuts by major central banks.
The record locks in elevated borrowing costs for a bond maturing in 2056, squeezing the fiscal space Chancellor John Healey has ahead of his first budget on October 28. Each quarter-point rise in gilt yields adds roughly £2.5 billion to annual debt-servicing costs, and the Office for Budget Responsibility already forecasts debt interest spending of £109 billion this year, equivalent to 8.4 percent of public spending.
Healey, who took office in July after Andy Burnham replaced Keir Starmer as prime minister, has pledged to respect the fiscal rules and not take "risks with the economy." In a speech Monday he described debt interest as the equivalent of the second-largest government department after health, exceeding the combined spending of defense, the Home Office, and justice.
The arithmetic facing the Treasury is stark. Pantheon Macroeconomics estimates higher gilt yields have cut fiscal headroom to roughly £13 billion from about £22.7 billion in the spring, leaving Healey needing to close an approximately £11 billion annual gap through tax rises or spending cuts before funding any new priority. Bloomberg Economics put the erosion from the global market selloff at about £12 billion.
Analysts are split on the scale of the response. Thomas Pugh, chief economist at RSM UK, said tax rises are "inevitable" come the autumn budget, warning that more borrowing to spend would fuel inflation and push gilt yields higher. Simon French, chief economist at Panmure Liberum and a former Treasury official, countered that the energy price shock has not yet produced "a smoking gun" flagging a large deterioration in headroom, making immediate remedial action unnecessary.
The strong demand at Tuesday's sale should not be read as comfort on cost. Buyers placed more than £85 billion in orders, roughly 20 times the amount on offer, with 71 percent of demand from domestic investors, according to the DMO. But that appetite reflects investors being paid handsomely for perceived risk on a bond whose coupon is now fixed for three decades.
The structural backdrop explains why 30-year yields sit at generational highs even when auctions clear. Long-dated conventional gilts once formed the backbone of British issuance, driven by pension-fund demand under liability-driven investment strategies. After the 2022 LDI crisis, when the Bank of England was forced to intervene as rapid yield rises triggered forced selling, many funds de-risked and cut their long-dated holdings. Dealers told the DMO in 2024 that demand from liability-driven investors had undergone "significant" structural change, and long-dated debt is now on course to make up less than 10 percent of the £246 billion issuance plan for this fiscal year.
Markets are pricing at least one more 25-basis-point rate hike by the Bank of England before year-end, a reversal from the two cuts expected before the conflict. Investors also anticipate the central bank will slow the pace of its gilt sales, or quantitative tightening, given criticism that its bond disposals have pushed up long-end yields. The 10-year gilt yield premium over German debt has narrowed on dovish UK signals, RBC strategists noted, pointing to softer economic data and Healey's emphasis on fiscal responsibility.
For UK taxpayers the path from Tuesday's auction to the October 28 budget is short. Elevated yields pass through to mortgage rates, since lenders price fixed-rate products against gilt benchmarks, and every week that 10-year and 30-year yields stay high further erodes the headroom determining how much Healey can fund public services without raising taxes. The 5.82 percent figure is not just a market statistic — it is the price the government locked in for public borrowing that will appear in Treasury accounts until 2056.
This article is for informational purposes only and does not constitute investment advice.