If you fall ill or get injured, seeing a medical professional quickly is critical. The NHS has a mixed record when it comes to this first step. As it stands, 43% of GP appointments in England take place on the same day as booking (about the same as pre-pandemic), while the share of patients seen within four hours of admission to A&E has slumped from 97% in August 2010 to just 76% in July 2025 (it fell as low as 65% in December 2022).

The system looks similarly creaky when it comes to getting treated by a specialist after an initial referral. Over the past decade or so, rising ‘referral to treatment’ (RTT) waiting times have become a key metric for highlighting the inefficiency of the country’s health system.

Long waits for treatment are not a new problem. According to the British Medical Association, in February 2020, prior to the Covid-19 crisis, there were already 4.57 million cases on a waiting list. At the start of the pandemic, the combination of the suspension of non-urgent services and changes to people’s behaviour meant that the number of people joining the waiting list actually dropped. But over the longer run, the pandemic had a massive impact on elective care, with the total waiting list surging from just under 4 million in June 2020 to around 7 million two years later.

Clearly, reducing waiting times is vital for people’s experience of the NHS as well as their health. Making progress in this area is also politically important - ending hospital backlogs is one of the key milestones within the government’s ‘Plan for Change’. But waiting lists are not just an acute challenge. To ease the pressure on the NHS, it is essential that policymakers take a preventative approach to health and reduce the flow of new patients onto the list. Targeting longer-run but preventable conditions - which are often associated with excess weight or obesity - is a sensible place to start.

Ensuring that 65% of patients are treated within 18 weeks of referral by March 2026 remains a cornerstone of the government’s mission to build a health service “fit for the future”. At a glance, the government is making slow but steady progress towards this self-imposed target. In May 2024, the share of patients on the waiting list who had been there for under 18 weeks was 58.8%. A year later this figure stood at 60.2%. Small steps, but steps in the right direction.

It’s a similar story if we compare the figures in nominal terms. Since Labour came to power, the number of people waiting longer than 18 weeks has fallen from about 3.2 million to just over 2.9 million. 

However, if we look further back and compare today’s performance with the situation in September 2021, the picture is more mixed. Over this longer timeframe, the number of people waiting for over 18 weeks has increased by more than a million - equivalent to the combined population of Bristol and Manchester.

The latest waiting list data from NHS England includes positive signals as well as areas where things are not going so well. For example, while the total number of people waiting for elective treatment has decreased slightly in recent months (having peaked at 7.7 million in October 2023), the headline figure remains stubbornly high - at around 7.3 million. This means that over the past couple of years, roughly one-in-eight people in England have been waiting for NHS treatment at any given time.

Zooming in, the number of people waiting 18-52 weeks has increased substantially over the past three and half years. In September 2021, about 1.5 million people were in this position. By June 2025, the figure stood at over 2.7 million - almost twice as many cases.

At the same time, the number of patients who have been waiting over a year has fallen substantially, perhaps reflecting the government’s initial focus on tackling “the very longest waits”. Since last May, the number of cases waiting 1-2 years has dropped from 318,000 to 205,000 - a 35% decrease.

In terms of its headline 65% target, the government is edging towards its goal for England. In September 2021, the share of people waiting less than 18 weeks for treatment was just shy of the target. A year out from the election - in May 2023 - it had slid to 58%. By June this year, it had risen slightly to 60%.

Of course, we should be careful not to focus too much on the target itself. While progress towards the 65% goal does represent a positive development, from a patient perspective there is little difference between waiting 17 and 19 weeks for treatment, despite this distinction looming large in the official statistics (being on target vs off target).

Focussing too closely on the 65% target could also obscure the areas of genuine progress. With longer wait times, for example, things have improved dramatically. Having peaked at 415,000 in November 2022, the number of people waiting 1-2 years from treatment to referral has roughly halved, dropping to 205,000 by June 2025. 

Better still, three and half years ago there were more than 11,500 people in England who had been on the NHS waiting list for over two years: today the figure stands at a little under 150 (it has been around this level since last spring). While these improvements do not drive the government towards its headline target for under-18 week wait times, they do still represent improvements in the functionality of the health system.

By the government’s own measures, NHS England is making modest progress on its waiting list target if we compare the June 2025 data with that of around a year ago. But hold today’s figures up against the numbers for September 2021 and it is clear a very steep climb remains. 

At the current rate of improvement - around two percentage points per year since the 2024 general election - it looks unlikely that the government will hit its 65% target by March 2026. In fact, at two percentage points per year the expected share of patients seen within 18 weeks would be around 62% by next spring, three percentage points adrift.

The goalposts are also set to move. The government has committed to raising the target share of patients seen within 18 weeks to 92% by March 2029. This is an ambitious goal: the last time this higher threshold was met was back in November 2015 - six prime ministers and eight health secretaries ago.

There is, of course, a complex relationship between RTT waiting times and the size and composition of the NHS waiting list. Research shows that a careful balance of activities is needed for the government to meet its 18-week target. Getting those medically fit to leave hospital discharged without unnecessary delays is another way capacity can be freed up within the system - something the Behavioural Insights Team (BIT) explored as part of a research project with Homerton Hospital last year.

That said, reducing the flow of new patients requiring treatment is likely to play an important role in easing pressure. As a leading cause of ill health across the UK, tackling obesity and other causes of preventable ill health is an obvious way to do this (by lowering demand for treatment of related conditions like cardiovascular disease, diabetes and some cancers).

The need for preventative action is especially pressing given the country’s ageing population. In 2022, there were around 12.7 million people aged 65 or over in the UK. The ONS predicts this could grow to 22.1 million by 2072 - around one-in-four people. As we get older our healthcare needs tend to increase and become far more expensive, further ramping up future demand for NHS services. 

Encouragingly, prevention is at the heart of the government’s 10 Year Health Plan for England. Policies such as the healthy food standard - which includes health targets for supermarkets, based on Nesta’s proposal for cutting obesity - could help lower demand on the system. Over the long run, if fewer people are living with obesity then the rate of related conditions should come down.

Focusing on reducing the number of people struggling with these conditions could allow the UK health system to “treat fewer people for fewer problems” in the future. Such an approach could also bring wider economic and social benefits that spill out beyond the health system. For now, a preventative approach to health, including a sustained focus on lowering obesity, remains critical to the future of the NHS, especially as we get older and our needs change.

Author’s note: this article uses data from NHS England’s Waiting List Minimum Data Set (WLMDS). The waiting list breakdown is calculated using RTT open (or ‘incomplete’) pathways. Unknown wait times are dropped from the analysis, apart from when considering waiting time groups as a share of the total list.