Bank tax would push up mortgage costs, warns UBS

**Lead**

UBS has warned that a proposed tax on British banks would inevitably raise the cost of mortgages, as lenders would pass the additional burden on to households. The advisory, published ahead of the autumn fiscal statement, argues that the levy – intended to fill a hole in public finances – could have the unintended consequence of making homeownership even more unaffordable for many families across the United Kingdom.

**Context**

The UK government has been exploring new revenue-raising measures as it grapples with high debt levels and persistent pressure on public services. Among the options under consideration is a targeted tax on banking sector profits, an idea that has gained traction among some backbench MPs and economic commentators who argue that major lenders have benefited from rising interest rates and should now contribute more to the national exchequer.

The banking industry, however, has pushed back, with UBS becoming the latest financial institution to flag the risks. In a research note examined by FORTIS NEWS, the Swiss-based investment bank stated that a levy of this kind would be treated as a cost of doing business, and that the most immediate response from retail banks would be to raise the pricing on new mortgage products and to tighten lending criteria. This would hit first-time buyers particularly hard, as they are already struggling with high property prices and elevated interest rates.

The warning comes at a time when the UK housing market is showing signs of fragility. House price growth has slowed significantly in recent months, and several major lenders have already withdrawn or repriced their mortgage offerings due to volatility in swap rates. Adding a new tax on top of these pressures, UBS argues, would risk triggering a deeper slowdown in property transactions and could further discourage investment in new housing development.

While the Treasury has not yet confirmed the exact structure of any banking tax, leaked policy documents have suggested that a headline rate of several percentage points on profits above a certain threshold could be introduced as early as the next fiscal year. UBS estimates that such a measure would reduce the after-tax profitability of UK retail banks, leaving them with less capital to support new lending. The bank's analysts write that the resultant cost of equity would necessitate a repricing of mortgage margins, which in practice would mean higher rates for consumers, regardless of the Bank of England's policy stance.

**Analysis**

The significance of the UBS warning lies not merely in its immediate impact on mortgage costs, but in what it reveals about the broader trade-off facing policymakers. On one hand, the government needs additional revenue to stabilise public finances and fund essential services. On the other, the housing sector – already under strain from affordability crises and supply shortages – is highly sensitive to any additional cost burdens. The proposed tax could therefore cut against other policy objectives, such as increasing homeownership and supporting the construction of new homes.

Moreover, the reaction from UBS underscores a growing tension between the financial sector and the political establishment. If banks anticipate that future governments will regard them as easy targets for taxation, they may become more cautious in their lending strategies and more aggressive in pricing risk. This could have long-term consequences for the availability of credit, not just for households but also for small and medium-sized enterprises, which rely heavily on bank finance. In the worst case, a poorly designed bank levy could tip the economy into a credit crunch, with knock-on effects on employment and investment.

The UBS analysis also raises important questions about the effectiveness of such taxes as a revenue-raising tool. If banks simply pass the cost to consumers, the net gain to the public purse may be lower than anticipated, while the distributional impact falls disproportionately on younger and less wealthy borrowers. Some economists have suggested alternative approaches, such as a windfall tax on excess profits that is clearly linked to extraordinary market conditions, rather than a permanent levy on the sector. However, the political appeal of a permanent bank tax remains strong, and the debate is likely to intensify over the coming weeks.

**Fontes**

– UBS research note on UK banks and mortgage pricing, October 2026. – HM Treasury statements on fiscal policy and revenue options. – Public statements from major UK banks on potential tax impacts. – Industry commentary from the Council of Mortgage Lenders and UK Finance.