NHS waiting lists: what you need to know

This explainer is part of a series Full Fact is publishing exploring a range of topics. We’ll be updating these articles on a regular basis—this article was last updated on 12 December 2024 and the information in it is correct as of then.

When people talk about “the waiting list”, they generally mean the “referral to treatment”, or RTT, waiting list for England specifically, because this is the part of the health service that the UK government controls.

RTT data records the number of cases awaiting planned treatment at the end of each month. It’s important to remember that the NHS also has many other types of waiting list—including so-called “hidden waiting lists”, for which data isn’t published. The number of cases in the RTT data is always a bit higher than the estimated number of people, because some people need treatment for more than one thing.

In the September 2023 data (published in November 2023), NHS England began to report a specific figure for the number of people waiting for treatment, as well as the number of cases.

How long are people waiting?

The size of the waiting list is important, because it gives us an idea of the scale of the backlog, and the workload that the NHS is facing. However, lots of people needing treatment isn’t necessarily a sign of a struggling health service if they are all being seen quickly.

From a patient’s point of view, the average time you can expect to wait is probably more important than the number of other people waiting.

One way to look at this is by counting the number of cases that involve different wait durations, including how many have not begun treatment within 18 weeks, which is considered every patient’s right under the NHS Constitution.

NHS England also publishes a figure for the median wait, in weeks, for cases where someone has not started to receive treatment yet.

Because it’s the median, this number shows what you would see if you put every case into a queue in wait-length order, then measured how long the case exactly in the middle had been waiting.

The median waiting time can fluctuate from month to month, and is somewhat seasonal, because some months of the year are generally busier than others.

Different cases have very different waiting times

NHS England data also shows us how many cases are waiting—and how long they’ve been waiting for—in different parts of the country, and for different types of treatment.

How do these waits compare historically?

The NHS was founded in 1948, and we simply don’t have waiting times data going back that far. And some of the later data was collected in different ways, which means it often isn’t possible to compare waiting lists that are decades apart.

We described how NHS waiting list data has changed over time in an article in 2023.

In short, any claims about waiting times throughout the whole history of the NHS are probably not reliable.

What about the rest of the UK?

This explainer only looks at waiting lists in England, which are what the UK government is responsible for, and which are often the focus of national political debate.

The health services in Wales, Scotland and Northern Ireland also publish regular RTT data, albeit not in the same form as England. For various reasons, this means it isn’t possible to make direct comparisons between the four nations on their headline measures. Some limited comparisons can be drawn between England and Wales, as we explained in a fact check in 2023.

You can read more about how the four nations compare on NHS performance in our explainer on the subject.