How large is the NHS maintenance backlog?
ERIC 2024/25 put the cost of eradicating backlog maintenance across the NHS estate in England at £15.9 billion, an increase of 15.7 per cent on the previous year. The high risk element reached £3.5 billion, up 28 per cent in twelve months.
The figure that matters most is a comparison rather than a total. Total estate running costs for the same year were £14.0 billion. The backlog now exceeds the annual cost of operating the estate, which means deferral has stopped being the cheaper option.
Why has the backlog grown so quickly?
Three mechanics compound. Deferred work becomes more expensive as condition deteriorates, so a repair postponed is rarely a repair avoided. Capital budgets have been drawn on to support revenue positions, reducing the funds available for planned work. And the estate contains a substantial proportion of buildings constructed before 1965, where the cost of bringing services up to current standards is high.
None of this reflects on the teams managing it. Estates functions have been asked to hold an ageing estate together with capital that arrives annually against problems that run over decades.
What changed in the 2026/27 financial regime?
From 2026/27, NHS trusts are expected to reach a breakeven revenue position as individual bodies rather than within a wider system position, and deficit support funding is being withdrawn.
That changes the character of the problem. Unplanned infrastructure failure was previously absorbed somewhere in the system. It now lands in a position that has to balance on its own, which makes the volatility of reactive spend a board-level concern rather than an estates one.
Which interventions should come first?
The instinct is to work down the backlog register from the largest number. A more useful sequence starts from the question of which failures would be most expensive if they happened next year.
Three tests, applied together, usually produce a defensible order. What is the clinical consequence of failure, including lost capacity and cancelled activity? What is the revenue cost of failure, including temporary works, decant, and premium-rate reactive labour? And what is the probability of failure inside the planning horizon?
An intervention that scores moderately on all three often outranks a larger item that scores highly on only one.
How do you evidence the case for capital?
Capital is released against business cases, not against condition surveys. The gap between the two is where most submissions lose ground.
A Green Book compliant case needs a counterfactual: what happens if we do nothing, expressed in money and risk over a defined period. That is difficult to construct when condition sits in survey reports, compliance sits in statutory registers, and cost sits in the finance ledger, each collected on a different cycle for a different purpose.
Bringing those datasets into one view is unglamorous work, and it is usually the difference between a case that is approved and a case that is deferred for further information.
What does a workable approach look like?
Start with a baseline that can withstand challenge. Prioritise against clinical risk and revenue exposure together. Build the case with an explicit cost of inaction. Then deliver in phases that respect clinical continuity.
We describe this as transitions rather than transformations. An operational hospital cannot absorb wholesale change, and a programme designed as though it can will stall.
Frequently asked questions
- How much is the NHS maintenance backlog?
- ERIC 2024/25 reported £15.9 billion to eradicate backlog maintenance across the NHS estate in England, including £3.5 billion of high risk backlog.
- What is high risk backlog maintenance?
- Work required to remedy defects that present a serious risk of major failure, breach of statutory requirements, or danger to people. It is the category that attracts regulatory attention first.
- Why does backlog maintenance affect revenue budgets?
- Because deferred planned work becomes unplanned reactive work, which is delivered at premium rates and often requires temporary measures, decant, or lost clinical activity alongside the repair itself.
- When should a trust start preparing a capital case?
- Ahead of the planning round, not during it. Assembling a defensible evidence base across condition, compliance, and cost typically takes longer than the submission window allows.
