UK Borrowing Costs Hit 19-Year High as Bond Selloff Spreads

UK medium-term borrowing costs hit a fresh 19-year high on 8 October 2026.

The yield on 10-year UK government bonds, the interest rate the government pays to borrow for 10 years, rose 0.06 percentage points to 5.515% by lunchtime in London. That was the highest since July 2007. Investors continued to sell government bonds around the world on fears of rising inflation. The Guardian

Yields on 20-year and 30-year UK bonds, known as gilts, rose to their highest levels since 1998. British long-term borrowing costs hit fresh multi-decade highs as part of a global bond selloff linked to a sharp rise in oil prices. U.S. News

France was hit hardest by the selloff as it tries to pass a budget. In Washington, US Treasury Secretary Scott Bessent increased buybacks of US government bonds in an effort to hold down long-term yields.

IMF Managing Director Kristalina Georgieva urged governments to tighten their belts and cut deficits in response to rising yields. The Fund holds its annual meeting next week in Bangkok.

UK Chancellor John Healey will deliver his first budget on 28 October. His predecessor Rachel Reeves had built a £24bn buffer against Labour's fiscal rules, limits on borrowing and debt, in the spring statement in March. Economists say higher borrowing costs and a weaker outlook for growth have likely wiped out half or more of that buffer.

UK government borrowing was £18.3bn in August 2026, almost a fifth higher than a year earlier, in data published in September. BBC Estimates reported by the FT put the cost of the Iran war to Britain's public finances at almost £12bn. Financial Times Healey is considering an energy subsidy costing more than £1bn to help mostly lower-income households ahead of the 28 October budget. Reuters

The Bank of England, Britain's central bank, is widely expected by investors and economists to raise interest rates at its November meeting to tackle rising inflation.

The 8 October rise followed six weeks of moves in both directions. On 10 September, the 10-year gilt yield had jumped 10 basis points, or 0.10 percentage points, to 5.378%, then a 19-year high. Reuters On 1 October, the UK 30-year yield hit 6%, while US government borrowing costs hit their highest since 2002. US long-term borrowing costs had hit a 25-year high in August. Monthly average data put the UK 10-year yield at 4.9318% in July and 4.9886% in August. There were brief falls as well. On 17 September, UK 30-year yields were on track for their biggest one-day fall since 20 May. As of 10 September, inflation had risen clearly since the start of the Iran war.

The broader context here is a collision between budget policy and inflation policy across advanced economies at once, not only in Britain. Oil feeds directly into inflation expectations and into the extra return investors demand to hold long-term bonds, called the term premium. With deficits still large, bondholders want more pay to hold longer debt while central banks can no longer be counted on to buy as much.

Looking at what this means for London, Healey has a narrower path than the £24bn headroom from March implied. Higher debt interest payments compound. Weaker growth means less tax revenue. Steps to ease household energy costs or support demand must be paid for inside fiscal rules that markets now watch tick by tick. That helps explain close attention to every pre-budget signal and to Bank policy in November.

Looking ahead to Bangkok, the question is whether coordination is possible. Georgieva's call for belt-tightening reflects Fund concern about debt if high yields last. Bessent's larger buybacks reflect a US Treasury focus on market functioning and handling bond sales. France shows the political constraint. Governments that must pass budgets struggle to cut spending when higher borrowing costs are already tightening conditions.

In my view, for investors in gilts, the open question is whether 5.515% on 10-year bonds and post-1998 highs on longer bonds will be enough to bring buyers back or invite more selling. One technical factor is the 0⅜% Treasury Gilt 2026, due to be repaid in full on 22 October 2026. The Debt Management Office has published average daily yields for standard gilts each month since April 1998, the yardstick that shows how unusual the current curve remains.