UK mortgage costs are facing unprecedented pressure as 30-year government bond yields topped 6% on Thursday for the first time since 1998, creating a cascade of financial challenges for homeowners. According to Reuters, Richard Merrett, managing director at mortgage firm Alexander Hall, faces a sudden trebling of his monthly housing costs from £550 ($728) to £1,650 when his ultra-cheap 1.14% mortgage deal expires in early 2027. The Bank of England estimates that over 5 million households are projected to see their mortgage repayments increase by end-2028, with almost 750,000 people facing average increases of £170 per month who took out fixed-rate mortgages before rates began rising in 2022. Britain's 2-year Sonia swap rate has risen 27 basis points in the last month to 4.68%, adding around a third of a percentage point to the cost of funding fixed-rate mortgages, as noted by Nicholas Mendes, mortgage manager at John Charcol.
The UK's debt challenges are part of a sharp selloff in bonds that is pushing government borrowing costs higher across the world. As reported by Reuters, borrowing costs from the US to France, Britain and Japan hit their highest in decades on Thursday, squeezing already pressured government finances. The UK's long-term borrowing costs reached 6% for the first time in almost three decades, with the rate on 30-year gilts rising six basis points to 6.01%. According to latest reports, the longer-dated 30-year UK gilt yield rose as high as 6.029%, its highest level since January 1998, and the first time since the 2012 euro crisis that a major economy has paid a rate that high. This represents the highest level since March 1998, when the last bond with that maturity from a Group-of-Seven nation touched this level. Gilt yields move counter to the value of the bonds, meaning their prices fall when yields rise, making it more expensive for governments to borrow from financial markets. As noted by IG's chief technical analyst Axel Rudolph, "Higher yields mean the Government has to pay more to finance its debt, putting further pressure on the public finances and making it harder to balance spending commitments with the need to keep borrowing under control."
The bond market rout has spilled over into the mortgage market as lenders pull sub-5% deals and mortgage approvals fall to their lowest levels since the end of 2023. According to Reuters, shortly after the start of the Iran war British banks withdrew more home loan products than on any day since the 2022 mini-budget crisis under then-Prime Minister Liz Truss. Mortgage approvals data published this week showed the lowest number since the end of 2023, another sign of how rising borrowing costs are hitting demand. House prices last month rose at their weakest pace since December 2025, according to Nationwide Building Society, reflecting worries about possible Bank of England rate hikes. Ashley Webb, senior UK economist at Capital Economics, expects UK house prices to rise by 2.5% in 2027 amid a lack of homes being put up for sale, but warns that the possibility of another jump in government borrowing in finance minister John Healey's first budget on October 28 could "limit the housing recovery."
The UK's debt is under pressure as climbing oil prices raise the risk that the Bank of England and other developed-market central banks will need to aggressively tighten policy to tame inflation. According to The Economic Times, investors think the central bank is likely to raise interest rates in November or December for the first time since the outbreak of the Iran war and another move is priced in for February. As noted by Rabobank's Jane Foley, head of G10 FX strategy, "The market is priced for quite a lot of interest rate hikes ... I don't think the bank (BoE) wants to hike interest rates because they're looking at household budgets, they're going to be hit by higher food prices, by higher energy prices, all of these things coming down the line." The swaps market is now pricing four rate hikes by the Bank of England by the end of next year, and a 70% chance of a fifth. Ten-year gilt yields hit the highest since July 2007, up 8 basis points at 5.510%, while 5-year yields at their highest since July 2008 reflect growing concerns about the UK's fiscal vulnerabilities. British government borrowing costs have risen more sharply than those of most other European governments since the start of the Middle East conflict on concerns about the country's reliance on natural gas for its home heating and power generation.
The UK's debt servicing costs are second only to its spending on health, according to government data reported by NDTV. The Office for Budget Responsibility forecasts that figure will keep rising in coming years. The government's debt challenges are particularly acute as Britain already suffers from the highest borrowing costs in the G7, with yields on the 10-year gilt climbing to 5.509%, the first time it has ticked past 5.5 per cent since July 2007. The 5-year gilt yield rose to an 18-year high, emphasising how expensive it is becoming to borrow, as the government paid the highest yield on a 10-year gilt auction since 1999 just days ago. However, the yield on UK 30-year bonds has dipped away from the 28-year high hit earlier this morning, back below the 6% level at 5.94%, showing some relief from the initial selloff pressure. As noted by NDTV, the government's debt challenges are particularly acute as Britain already suffers from the highest borrowing costs in the G7, with the 5-year gilt yield rising to an 18-year high, making it increasingly difficult for the Chancellor to balance spending commitments with the need to keep borrowing under control.
