THE ERIC RECKONING · Article 2 of 8
The £15.9 Billion Question: What the Backlog Figure Actually Measures
NHS Estate Directors · Capital Planners · FM Suppliers · Property Investors with NHS Exposure · Procurement Leads
The NHS maintenance backlog has reached £15.9 billion. The 28% jump in high risk backlog in a single year is being cited as evidence of accelerating crisis. Before you build a capital case, price an FM contract, or design a procurement framework on those numbers, read what they actually measure and what the mathematics of estate deterioration means for every figure in the dataset.
£15.9bn
ERIC backlog 2024/25 — cost to Condition B minimum only
£37bn
Darzi capital shortfall — the gap above what ERIC measures
28%
single year increase in high risk backlog 2023/24 to 2024/25
The number everyone quotes and almost nobody interrogates
In October 2025, NHS England published the 2024/25 ERIC data. The headline figure was £15.9 billion, up 15.7% on the prior year. High risk backlog reached £3.5 billion, up 28% in a single year. The total cost of running the NHS estate in 2024/25 was £14.0 billion, meaning the backlog now exceeds annual running costs. The NHS Confederation said the scale was deeply worrying. The King's Fund noted the figure exceeded the entire capital budget for the financial year. Every response treated £15.9 billion as a straightforward measure of how much the NHS estate needs spending on it. It is not. And the gap between what the figure measures and what most people assume it measures has direct consequences for every capital case, FM contract, and procurement strategy built on it.
£15.9 billion is the cost of controlled decay, not recovery. It measures what is needed to stop the estate getting worse. Not what is needed to make it fit for modern healthcare. Not what Lord Darzi found was missing.
Condition B: the definition that changes everything
The ERIC backlog is defined by NHS England as the investment needed to restore buildings to a defined condition based on assessed risk, excluding planned maintenance. That defined condition is Condition B. The minimum acceptable standard. Not good condition. Not fit for purpose. The floor below which the estate cannot fall without direct risk to patients and staff.
The NHS condition classification runs from A to D. Condition A is as new or recently upgraded. Condition B is acceptable, meeting minimum statutory requirements. Condition C is poor, not meeting current standards. Condition D is bad, life expired, requiring immediate action.
The ERIC backlog measures the cost of moving everything currently in Condition C and D up to Condition B. The cost of getting to acceptable. What comes after, reaching good condition, meeting modern clinical standards, replacing ageing plant that is functional but at or beyond design life, is not in the figure. Lord Darzi- independent review identified a £37 billion capital investment shortfall relative to peer countries over the 2010s. The ERIC £15.9 billion and the Darzi £37 billion are measuring different things. The ERIC figure is the cost to minimum standard. The Darzi figure reflects the cumulative historic underinvestment that allowed the estate to reach this position in the first place. Taken together, they show both the immediate floor and the magnitude of the gap above it. Neither alone tells the full story.
The Condition C creep: why the 28% jump is worse than it looks
The 28% increase in high risk backlog in a single year is not simply the result of new problems appearing. It reflects a dynamic that experienced estates professionals recognise but that the published commentary rarely explains: backlog cannibalization.
A trust receives capital and directs it rationally toward high risk items, the most urgent problems, the ones that could cause patient harm or service closure. Those items get addressed. The high risk category reduces. But while the estate team is focused on the top tier, the Condition C items in the significant and moderate categories continue to deteriorate. Assets that were significant risk eighteen months ago are now high risk. Assets that were moderate risk are now significant. The capital cleared the top of the queue, but the queue moved up behind it.
The 28% single year jump in high risk backlog is partly the result of real deterioration and partly the mathematical reality of an estate where the moderate middle is collapsing into the critical top tier faster than investment can clear it. Addressing high risk items without simultaneously maintaining significant and moderate risk items means the high risk category refills from below.
This is why the backlog trajectory cannot be broken by targeting only the highest risk tier. An estate strategy that clears high risk items while deferring moderate and significant risk maintenance is running on a treadmill. The capital that appears to be making progress is largely offsetting the deterioration it did not prevent.
Self assessed condition: the variation you cannot see in the national figure
The £15.9 billion is a national aggregate of 209 individual trust backlog assessments. Each trust surveys its own estate, classifies asset condition, calculates the cost of eradication, and submits. NHS England aggregates those submissions into the national figure.
The methodology for backlog assessment is documented by NHS England and is consistent in principle. In practice, application varies between trusts in ways the national aggregate cannot reveal. In Baachu’s experience across NHS FM contract work, differences of 20 to 30% in reportedbacklog between comparable estates are not uncommon where those differences reflect how assessors classified borderline conditions rather than meaningful differences in physical state. An assessor applying conservative assumptions to a borderline Condition B or C asset will produce a higher backlog figure than one applying liberal assumptions to the same asset. Both work within the methodology. Both pass validation. The figures look comparable in format but may not reflect comparable physical reality.
This variation matters more in 2026 than at any prior point in ERIC’s history. Because 15% of every trust’s operational capital allocation is now tied to its Critical Infrastructure Risk score, the methodology applied to borderline condition assessments has a direct financial consequence. The trust that assesses comprehensively and reports conservatively receives more capital. The trust that assesses optimistically receives less. Both are acting rationally within the system as designed.
The survey shelf life problem
The ERIC backlog figure is only as current as the condition survey it is based on. NHS England recommends regular condition surveys but does not mandate a specific frequency or require the survey to be carried out by an independent party.
A trust completing its 2024/25 ERIC return using condition data from a survey carried out in 2019 is reporting a five year-old physical picture adjusted by professional judgement. In Baachu’s experience, the margin of error on a return based on data of that age is substantial. Five years of maintenance deferrals, plant aging, and undocumented reactive interventions represent a material gap between the survey baseline and current physical reality.
The person signing the ERIC return in many trusts is the Director of Estates, whose professional KPI is to reduce backlog. We are asking the person being assessed on the condition of the estate to be the one who measures it. Without independent verification, the quality of the backlog figure depends entirely on the rigour and honesty of that individual assessment process. Most estates professionals approach it with integrity. The structural conflict of interest exists regardless.
The Risk
FM suppliers pricing long term NHS contracts against ERIC backlog data need to model not just the current high risk items but the rate at which moderate and significant risk assets are degrading into high risk. The reactive demand in years three and four of the contract may be substantially higher than the mobilisation day ERIC figure suggests.
What the trajectory actually measures
The backlog figure has grown from £6.5 billion in 2018/19 to £15.9 billion in 2024/25, a 145% increase over six years. This trajectory is used to justify NHS capital investment arguments, the New Hospital Programme rationale, and the distribution of the £6.75 billion Estates Safety Fund. That trajectory is substantially right as a directional indicator of real deterioration and historic underinvestment. It is not reliable as a precise time series. NHS England’s own data quality statements note that data are not presented alongside earlier years because year on year comparability cannot be assumed. Definition changes, methodology refinements, and post publication corrections across the period mean that comparing any given year’s figure directly to a prior year’s figure may not be measuring the same thing.
The 38% jump from £6.5 billion to £9.0 billion between 2018/19 and 2019/20 coincided with updated NHS England guidance on assessment methodology, not purely with physical deterioration. The specific trajectory figure of 145% combines real decline, methodology maturation, and definitional change. The investment case stands on physical reality, not on the precision of a trajectory that NHS England itself cautions against treating as a consistent time series.
| The ERIC headline | The reckoning |
|---|---|
| £15.9 billion backlog 2024/25 | Measured to Condition B minimum standard only. Excludes cost of Condition A restoration and end of life plant replacement. |
| 28% increase in high risk backlog in one year | Partly real deterioration, partly Condition C assets degrading upward as investment clears the top tier without maintaining the middle. |
| 145% growth over six years | Combines physical decline with methodology maturation and definition changes. NHS England cautions against year on year comparison. |
| Mandatory Chief Executive sign off | Self reported by the organisation whose capital allocation the figure influences under the new 85/15 formula. |
| National coverage across 209 trusts | Excludes 100% of primary care and GP estate. Covers roughly half the physical NHS estate by building count. |
What this means for you
If you are an NHS estate director making a capital case under the new 85/15 formula, your ERIC CIR score is now directly shaping your funding. But the backlog figure you present to your board for wider investment needs is a Condition B floor. Your board should understand what it would cost to go further, what modern clinical standards require, and how the Darzi capital shortfall analysis frames the gap between minimum standard and genuine fitness for purpose.
If you are an FM supplier pricing an NHS contract, the ERIC backlog figure tells you what the trust assessed to Condition B. It does not tell you what an independent survey would find, and it does not model the rate at which Condition C assets are moving toward high risk during your contract term. Both matter for pricing reactive demand. The BCIS Intelligence Series examined the same structural limitation in cost benchmarking. BCIS OpX is an aggregated average of FM operational costs from a contributor base that has been narrowing since the 2022 RICS spin out. ERIC backlog data and BCIS OpX share the same fundamental problem: both are retrospective aggregates that cannot be substituted for estate specific intelligence. Using them together without awareness of their shared limitations produces two incomplete pictures that look more authoritative in combination than either deserves.
Article 3 examines what the self reporting structure of ERIC means in practice for the specific people who complete these returns.
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This article represents Baachu’s independent analysis based on publicly available information, including NHS England ERIC publications and data quality statements. Baachu Works Limited has no commercial relationship with NHS England, NHS Property Services, or any FM provider, NHS trust, or estate services firm referenced in this series. This article is not legal or financial advice.