headroom

However, in its last estimate in March, the OBR said the chancellor only had £10bn headroom to meet these rules, which it called a "very small margin".

But she faces difficult fiscal decisions in the run-up to her budget, after the government watered down its planned welfare savings and largely reversed winter fuel allowance cuts - decisions which narrowed her budget headroom.

She may choose to rebuild the so-called "headroom" to give her a better chance of meeting her self-imposed borrowing limits.

The IMF reckons one assessment would "promote further policy stability" and potentially reduce the pressure on the government's buffer figure, which is often referred to as "headroom".

In March 2025, the OBR projected that she had just £9.9bn of "headroom" against this rule, a very small amount of leeway given the size of overall government spending and borrowing.