Chancellor Rachel Reeves is facing some difficult choices in the upcoming Spending Review, which sets the budgets for all government departments over the next few years.

The review will confirm how much taxpayers’ money will be spent on the NHS and other public services used by millions, as well as how much money the government plans to invest in projects like new public transport schemes.

The Spending Review will be delivered by Reeves on Wednesday, 11 June.

In October she set department budgets for 2025-26, and will now confirm spending allocations for the following three to four years.

Reeves has already set out what is known as the “spending envelope” – how much total government spending will rise by over the period.

On Wednesday this will be broken down by department.

The review covers two categories of spending:

• day-to-day spending which includes things like salaries, supplies and other administration costs. This is known as “resource” spending
• investment which includes funding for infrastructure as well as building things like new schools, hospitals and roads. This called “capital” spending

Wednesday’s Spending Review will set out day-to-day expenditure for three years and investment spending for four years.

Government borrowing – which is the difference between how much it spends and how much it raises from taxes – grew to £20.2bn in April.

That was £1bn higher than the same month in 2024, and more than some economists expected.

Although tax revenue increased in April, notably as a result of the increase in the amount of National Insurance Contributions (NICs) paid by employers, so did spending.

This was largely because of increases in pensions and other benefits and other pay rises as well as higher borrowing costs.

Meanwhile, the financial buffer that allows Reeves to meet the government’s two self-imposed fiscal rules is very slim.

The rules are that:

• day-to-day government spending should be paid for with tax revenue, not borrowing, and
• the amount of government debt should fall as a share of national income by the end of the current parliament in 2029-30

The government is currently forecast to have a budget surplus of £9.9bn at that point – which is the third-smallest on record.

This surplus is often referred to as “headroom” and theoretically acts as buffer against an economic shock or an increase in spending.

But because the projected surplus is so small, it is very vulnerable, Between the Autumn Budget and Spring Statement in March, it was wiped out mostly because of higher debt interest payments as well as sluggish economic growth.

As a result, Reeves announced a £14bn package of savings in March, including £4.8bn of welfare cuts.

The latest official data suggests that the UK economy could be strengthening. It grew by 0.7% between January and March, which was better than expected.

However, it is not clear whether that growth will continue, especially as US President Donald Trump’s US tariffs hit the UK and wider global economy.

The government has already announced how much total spending on day-to-day running costs and on investment will increase by over the years covered by the Spending Review.

The “relatively modest” rise could mean that “sharp trade-offs are unavoidable”, according to the Institute for Fiscal Studies (IFS) think tank.

For example, the government has said that the overseas aid budget will be cut to fund a sharp increase in defence spending.

Spending on defence will rise from 2.3% of gross domestic product (GDP) to 2.5% by 2027. That’s around an extra £5bn a year. Ministers want to increase defence spending further to 3% by 2034.

As yet, there are no details about how much money will be allocated to the Department of Health and Social Care (DHSC), which oversees the NHS.

But due to its size – nearly 40% of total departmental expenditure this year will go to DHSC – its budget can have a considerable impact on those of other departments.

What is known is the government will extend free school meals to around 500,000 children whose parents are receiving Universal Credit, regardless of their income. Education Secretary Bridget Phillipson said the government has set aside £1bn to fund this.

Schools in England are set to receive an extra £4.5bn, the Observer has reported, which will help pay for this expansion of free school meals, as well as repair buildings and increase funding for children with special needs.

Reeves has confirmed that the government will revise its controversial decision to limit Winter Fuel Payments to those in receipt of means-tested benefits.

But while the government will share some information about who will receive the payment as part of the Spending Review, full details will not be released until the Budget later in the year.

Also unknown is whether Reeves will say anything about the two-child benefit cap. Phillipson has said the government is looking at scrapping it but admitted doing so would “cost a lot of money”.

The government has said it wants to increase investment.

Reeves has tinkered with the way that debt is measured to free up more than £100bn to fund building, research and development as well as other major projects.

On Wednesday, the chancellor announced a £15.6bn package to fund extensions to trams, trains and buses in Greater Manchester, the Midlands as well as Tyne-and-Wear, after criticism that too much infrastructure spending targeted London and the south-east.

An £86bn package has also been announced for the science and technology sector for this Parliament, which is aimed at funding research into areas such as drug treatments and longer-lasting batteries.

There have been reports that Reeves could announce a new nuclear power station in Suffolk.

Sizewell C, a project that is jointly owned by the UK government and the French state-owned energy giant EDF, wants to begin construction of a power station that will be funded by taxpayers and private investors.

The government may also set out detailed plans to build small modular reactors (SMRs) – mini nuclear power stations – in England and Wales.