Drone sightings around prison walls have surged by 43% in a single year. The drug crisis in prisons is now impossible to ignore. Nearly half of all people held in England and Wales carry an identified drug problem. Yet the government has failed to spend tens of millions of pounds it already set aside to tackle it.

The National Audit Office (NAO) published its findings in February 2026. The report scrutinises the Ministry of Justice and the Department of Health and Social Care. It raises urgent questions about priorities, accountability and the human cost of inaction.

How Bad Is the Drug Crisis in Prisons?

In April 2025, approximately 40,000 people in prisons in England and Wales had an identified drug problem. That figure represents around half the entire prison population. The prison drug problem has also been getting worse at speed.

HMIP found that 39% of adult male prisoners said it was easy to get illicit drugs in 2024 to 2025. Three years earlier, in 2021 to 2022, that figure stood at just 24%. An additional 11% of men and 19% of women said they developed a drug or alcohol problem since arriving.

Between December 2022 and December 2024, the Prisons and Probation Ombudsman investigated 833 deaths in custody. Of those, 136 (16%) were drug related.

These are not abstract numbers. They represent people in a state’s care, in a setting where access to illicit substances should be tightly controlled.

Drones, Synthetic Opioids and the Changing Nature of the Prison Drug Problem

Criminal methods of smuggling are evolving rapidly. The substances themselves are becoming harder to detect and more dangerous. That combination is what makes tackling the prison drug problem so difficult.

Drone sightings around prisons in England and Wales jumped by more than 750% between 2019 and 2023. They then rose by a further 43% between 2023 to 2024 and 2024 to 2025. Criminal organisations now use commercially available drones to drop drugs directly into prison yards, often at night.

Finds of novel psychoactive substances, particularly synthetic opioids, rose by 45% between 2023 to 2024 and 2024 to 2025. These substances are more potent in smaller quantities than traditional drugs and harder to detect with current testing methods. Prison staff are dealing with substances they have never encountered before, with very little guidance on the risks.

HMPPS only added a specific risk about drone activity to its national risk register in January 2025. By that point, it had already recorded rising drone sightings for six consecutive years. The NAO noted this timing with clear concern.

Millions Left Unspent While Prisons Struggled

The most striking finding in the report is not the scale of the threat. It is what the government chose to do with the money it already had.

Between 2019 to 2020 and 2021 to 2022, HMPPS received a £100 million security investment programme. It spent only £75 million of it. Gate security saw the largest underspend. HMPPS blamed delays in recruiting staff and procuring equipment.

A second tranche of funding told a similar story. Under the cross-departmental strategy From Harm to Hope, HMPPS received £114 million covering 2022 to 2025. Department-wide efficiency requirements cut the budget to £97 million. HMPPS then spent just £67 million of that, or 69% of the revised total. In 2022 to 2023, ministers did not sign off the budget until July. That meant HMPPS spent only 31% of its allocation in the first year.

Only seven of a planned 18 Drug Recovery Wings ever launched. Recruitment into funded roles fell behind schedule. A health training package budgeted at £5.6 million ended up costing just £80,000 after officials redesigned the scheme.

These figures sit uncomfortably alongside what prison governors reported. Broken scanning equipment went unrepaired for months. Urgent window security works stalled for years.

Staff Shortages and a Crumbling Prison Estate

The prison drug problem does not exist in isolation. A chronically underfunded estate makes it worse.

The maintenance backlog across the prison estate doubled from £0.9 billion to £1.8 billion between February 2020 and September 2024. Many prison windows, particularly in older and listed buildings, were never designed to block drone deliveries. At HMP Manchester, a listed building, HMPPS approved funding for secure windows and netting in 2021. In early 2025, the work was still not complete. HMPPS told the NAO it expected another seven years before the job is done.

An internal audit found 40% of prisons reviewed lacked complete training records for X-ray body scanners and similar equipment. Around a third could not show they had carried out required quality checks on searching. In April 2025, HMPPS cut the number of prevent managers in its Counter Corruption Unit by 50%. That decision came despite intelligence reports on staff corruption reaching a record high of 113,000 in 2024.

Healthcare Funding for the Drug Crisis in Prisons Is Shrinking in Real Terms

NHS England spent £226.4 million on mental health and substance misuse treatment in adult prisons in 2024 to 2025. That figure looks like a cash increase on the £202.9 million spent in 2020 to 2021. In real terms, however, it represents a 5% decrease.

The NAO estimates around £88.8 million of that combined spend goes specifically to substance misuse treatment. But where a prisoner is held significantly affects what support they receive. In 2024 to 2025, London spent around 72% more per prisoner on substance misuse treatment than the East of England. NHS England has not investigated that gap.

In February 2025, NHS commissioners flagged serious pressure on healthcare delivery in 35 prisons. NHS commissioners rated 14 of those as “very likely to result in harm to patients.” Nearly 160,000 substance misuse appointments went unattended in 2024 to 2025. That is around 35% of all appointments. Some of those will be prisoner choice. Others reflect lockdowns, staffing gaps and scheduling failures that nobody is systematically tracking or fixing.

The Real Cost of Ignoring the Prison Drug Problem

The NAO accepts that calculating a precise total cost of tackling the prison drug problem is not possible. Security spending serves multiple purposes. Drug treatment and mental health services overlap. Some costs, such as emergency ambulance callouts following overdoses, go entirely uncaptured.

But the costs of inaction are clearly higher than the costs of intervention. Prisoners who use drugs frequently reoffend after release. Violence and debt linked to prison drug economies put pressure on staff and disrupt rehabilitation programmes. In some cases, they cost lives.

Dame Carol Black’s independent review found around 50,000 people serve short sentences each year because of addiction. They are there for the crimes they committed to fund it. For many, prison is the first sustained contact with treatment services. Whether those services reach them, and whether the prison is stable enough to deliver them, has lasting consequences.

What the NAO Wants to See Change

The NAO sets out clear recommendations. HMPPS should respond more urgently to identified security weaknesses. Senior prison leaders should be able to bid directly for responsive security investment rather than waiting on slow central approvals. Maintenance contracts need reviewing to allow faster action on urgent work.

HMPPS and NHS England need to share data more consistently. That includes figures on prisoners observed to be under the influence. Currently, entire prisons submit no data for months at a time. That makes it impossible to allocate resources or measure progress on the drug crisis in prisons.

Health commissioners should use needs assessments to drive funding decisions rather than simply adjusting historic contract values each year. The government also needs to renew its cross-departmental partnership. The current arrangement runs on a short extension while NHS England prepares for abolition in 2027.

The drug crisis in prisons will not fix itself. The NAO has made that clear. The tools, the data and, in some cases, the funding already exist. What remains to be seen is whether the government will act on them.

Report reference: The Costs of Tackling Drug Harms in Prisons, National Audit Office, February 2026, HC 1643.

Source: dbrecoveryresources