The UK government won't admit it, but tax rises are coming — and there are no good options

The National Institute of Economic and Social Research (NIESR) projects the UK government faces a £41.2 billion deficit by FY2029-30, necessitating substantial tax adjustments in the Autumn Budget to meet its self-imposed fiscal rules. Chancellor Rachel Reeves confronts an "impossible trilemma": simultaneously adhering to fiscal targets, fulfilling spending commitments, and upholding manifesto promises against tax rises for "working people." NIESR suggests options like increasing VAT or income tax, but notes that politically acceptable tax increases often generate minimal revenue or create significant economic distortion, indicating challenging decisions for the Treasury.

Analysis

The UK government faces a significant fiscal credibility challenge, underscored by a National Institute of Economic and Social Research (NIESR) forecast of a £41.2 billion budget deficit by the 2029-30 fiscal year. This projection directly conflicts with Chancellor Rachel Reeves' self-imposed 'stability' and 'investment' rules, which require a balanced budget and a falling debt-to-GDP ratio. The situation is framed as an 'impossible trilemma' where the government cannot simultaneously meet its fiscal targets, honor existing spending commitments, and adhere to its manifesto promise of not raising taxes on 'working people.' With spending plans fixed, NIESR concludes that raising taxes is the only available lever, yet all options present significant political and economic drawbacks. Potential hikes to VAT or income tax, while effective at raising revenue, are either regressive or break explicit promises. Other measures, such as raising capital gains tax or reversing National Insurance cuts, risk disincentivizing saving or harming employment. The Prime Minister's reluctance to acknowledge the NIESR figures, while not ruling out future tax increases, injects a high degree of policy uncertainty ahead of the Autumn Budget, creating a negative outlook for business confidence and household finances.

Key Decisions for Investors

• Investors should closely monitor the upcoming Autumn Budget for any deviation from the government's fiscal rules or manifesto pledges, as this will be a key catalyst for UK asset prices.
• Given the high probability of tax increases that could reduce household disposable income, such as a VAT or income tax hike, it is prudent to reassess exposure to UK consumer discretionary sectors.
• The potential for higher corporation taxes or a reversal of National Insurance cuts poses a significant risk to UK corporate earnings and business investment, warranting a cautious stance on UK-focused equities.
• The heightened fiscal uncertainty and the debate between borrowing and taxation could introduce significant volatility into the UK Gilt market, requiring investors to be prepared for shifts in government bond yields.