Charlie Bean, a former deputy governor of the Bank of England and member of the Office for Budget Responsibility’s budget responsibility committee, has warned Chancellor Rachel Reeves that her current fiscal planning leaves insufficient buffer to manage public finances. The headroom she has allocated—just under £10 billion—is far tighter than the roughly £30 billion buffer previous chancellors have typically maintained. Bean argues that such a narrow margin leaves the government vulnerable to minor forecast variations and forces frequent micro‑adjustments to tax and spending plans just to align with the OBR’s five‑year projections. In October 2024 Reeves raised taxes by around £40 billion, chiefly to fund public services, but the decision failed to yield meaningful fiscal slack. By March of this year the headroom she had secured was evaporating, triggering the government’s hurried efforts to find £5 billion in welfare savings—a move ultimately blocked by backbench opposition. Reeves’s twisted fiscal tightrope stems from the limited buffer she deliberately built into her autumn budget, a choice Bean says was the “original sin”. Bean stresses that with total public spending in the region of £1.25 trillion, a headroom of less than £10 billion is negligible within the margin of typical forecasting errors. He points out that the OBR’s projections, extending over five years, are inherently uncertain, making it imprudent to cling to such a slim cushion. He contends that a more prudent approach would be to adopt the £30 billion buffer that has long been the norm. With the headroom disappearing, Reeves faces pressure to implement further tax increases. Creating an additional £20 billion buffer, Bean notes, would require measures equivalent to a 2p rise in both the basic and higher rates of income tax. Such a step would need to be announced in the autumn budget, though no detail has yet been provided. Bean also cautioned against knee‑jerk spending cuts in response to weaker economic forecasts. In March he warned that the government risked falling into a cycle of “fine‑tuning” its tax and spending framework to chase elusive five‑year targets. He urged Reeves to avoid immediate austerity and suggested she could instead commit to extending income tax threshold freezes as a contingency rather than a live policy focus. Despite these pressures, Reeves’s team attributes the constrained headroom to the “poor fiscal inheritance” left by the previous government. They make the case that higher taxes were inevitable given the scale of the deficit and the demand for public services. Reeves has remained publicly firm that her fiscal rules will be adhered to and that budgeting discipline is essential to restoring trust in UK public finances . Ultimately Bean’s warning is clear: with such a thin fiscal cushion, the Chancellor’s room for manoeuvre is perilously limited. Unless the government expands or replenishes that buffer, it risks being forced into repeated reactive decisions—whether tax tinkering or abrupt policy reversals—to stay within its own financial framework. If Reeves is to avoid ongoing volatility and backbench revolts, she will need to rediscover the room for manoeuvre that Bean suggests her predecessors always secured....