The UK asylum backlog: explained

In recent years, the UK’s asylum backlog has been at the heart of the debate over immigration.

Since the 2019 general election it has increased substantially, reaching the highest level on record in June 2023, and falling since. Labour has pledged to “clear the asylum backlog”, and has made substantial changes to the way in which asylum cases are handled since coming into government.

The Conservative government’s progress against its commitment to “abolish the backlog” was also the focus of political debate ahead of the 2024 general election, after it introduced a series of new laws which would have prevented many asylum seekers from having their claims considered in the UK.

This article looks at the current scale of the asylum backlog, how the previous government’s asylum policy has impacted the processing of applications, and the current government’s approach.

This explainer is one of a series Full Fact is publishing exploring a range of key political topics. We’ll be updating these articles on a regular basis—this article was last updated on 8 July 2025 and the information in it is correct as of then.

What is the asylum backlog?

‘Asylum backlog’ is an unofficial term, the definition of which has been the subject of some debate in recent years. But broadly speaking, the term is usually used to refer to the queue of asylum applications waiting to be processed by the government.

When the government talks about the asylum backlog, it’s usually referring to applications waiting for an initial decision, and that is what we’ve primarily focused on in this article. Initial decisions include grants of refugee or humanitarian protection, other forms of leave to remain in the UK, and refusals.

Official immigration statistics show that at the end of March 2025, there were 78,745 asylum applications awaiting an initial decision—an 8% decrease since the end of June 2024 (shortly before Labour formed a government), and a 13% decrease compared to the end of December 2024. These outstanding cases related to 109,536 people, including both main applicants and their dependents.

Backlogs within a backlog?

Over the past few years there have been significant changes to asylum policy, which have led to asylum cases being considered differently depending on when applicants entered the UK.

As a result of the Nationality and Borders Act 2022 (NABA), which received Royal Assent on 28 April 2022, most asylum seekers who claimed asylum in the UK on or after 28 June 2022 (when the relevant provisions came into force), and who had previously passed through or have a connection to a different safe third country, may have their claims deemed ‘inadmissible’. That means they would not have their application considered and would have no right to appeal.

The list of what counts as a “safe third country” is set out in law and covers 31 European countries, including France, where many small boat crossings originate.

This has essentially meant the asylum backlog has been split into two groups:

• applicants who arrived before 28 June 2022, whose claims are processed under the old asylum laws—the previous government labelled this group the “legacy backlog”, but it is now being referred to in official data as “pre-NABA asylum cases”;
• applicants who arrived on or after 28 June 2022—the previous government labelled this group the “flow backlog”, but it is now being referred to as “post-NABA asylum cases” (the current government has further split this group into two cohorts, as we’ll explain later).

Pre-NABA or ‘legacy backlog’ cases

The Conservative government often talked about the “asylum backlog” when it was in fact only referring to what it termed the “legacy backlog”. We fact checked then-Prime Minister Rishi Sunak and other ministers who failed to make this distinction clear when talking about the asylum system back then.

Official immigration figures (published quarterly) show that as of 31 March 2025 most of the 98,659 “legacy backlog” or “pre-NABA” cases from June 2022 had received an initial decision, with 1,194 cases still outstanding.

We wrote in January 2024 about the Conservative government’s claim to have “cleared” the “legacy backlog” (note though that the figures discussed in that fact check have since been revised).

Post-NABA or ‘flow backlog’ cases and inadmissibility

When it comes to the remaining backlog of outstanding asylum cases, the picture gets more complicated.

Changes to asylum law made over the past few years meant that under the previous government even within this group—the “flow”, or “post-NABA” backlog—cases were treated differently depending on exactly when people arrived.

As explained above, the Nationality and Borders Act 2022 means that applicants who arrived on or after 28 June 2022 who travelled through a “safe third country”, or have a connection to one, “may” have their claims deemed inadmissible.

Oxford University’s Migration Observatory explains: “In theory, the government would attempt to remove them to that country or any other safe third country. In practice, if they could not be removed (for example, because no safe country was willing to take them back), they would eventually be admitted to the UK asylum system.”

However the Illegal Migration Act 2023 set out further changes to the rules around inadmissibility. The relevant provisions in this legislation provided that most asylum seekers who entered the UK irregularly on or after 20 July 2023 (for example, by small boat or in the back of a lorry), “must” have their application deemed inadmissible, meaning the Home Office would legally not be able to make a decision on their claim.

The Act also placed a legal duty on the home secretary to remove these asylum seekers to a safe third country.

Another group of asylum seekers within this “flow” or “post-NABA” backlog, consisting of people who arrived on or after 7 March 2023 but before 20 July 2023, do not fall under the same “duty to remove” as those who arrived on or after 20 July 2023, but also cannot be granted leave to remain except in limited circumstances.

The different pieces of legislation outlined above do not apply to unaccompanied asylum seeking children, as well as some trafficking victims. They also do not apply to asylum seekers who initially arrive in the UK legally, and later go on to claim asylum.

These new provisions from the Illegal Migration Act were not brought into force by the previous government, and the Labour government has confirmed that it will not proceed with plans to send asylum seekers to Rwanda, which had formed a key plank of the previous government’s proposals to tackle the backlog through safe third country removals.

The Labour government has made further changes to how these laws are applied. On 22 July 2024, home secretary Yvette Cooper MP laid a statutory instrument to allow the government to process asylum cases made since March 2023. The Border Security, Asylum and Immigration Bill, which is currently before Parliament, will repeal the ‘duty to remove’ set out in the Illegal Migration Act.

This means that “post-NABA” cases can now be processed, but will still be subject to a “higher standard of proof” than “pre-NABA” cases.

At the end of March 2025 there were a total of 77,551 “flow backlog”, or “post-NABA”, cases. Of these, 33,192 were applications raised between 28 June 2022 and 22 July 2024, which were unable to be processed ahead of the changes made by Labour. The government has described these cases as “cohort 2” cases, with the remaining 44,359 applications made since 23 July 2024 described as “cohort 3” cases.

Has the backlog been ‘cleared’, or simply moved?

The term ‘asylum backlog’ is sometimes also used to encompass cases that have received an initial decision but are currently subject to an appeal or reconsideration, or judicial review. The government has not published the number of such cases as part of its immigration statistics beyond the end of December 2022, when there were 4,051 cases (relating to 5,342 people) pending further review.

We do however have more recent data showing the total number of “work in progress” asylum cases published in the government’s migration transparency data. These figures include both cases awaiting an initial decision, which this explainer has focused on above, and those which have received an initial decision but are awaiting further action, and therefore are still part of the government’s overall asylum caseload.

This second category includes cases which are subject to an appeal, those who have had their application rejected and are subject to removal action, and other ‘post-decision’ cases.

The figures—which show the situation at the end of June each year—show that a decrease in the number of cases awaiting an initial decision does not necessarily mean a corresponding decrease in the overall asylum caseload, as cases which were awaiting an initial decision may still require further action.

For example, at the end of June 2024 the number of cases awaiting an initial decision had decreased compared to the previous year, but the overall asylum work in progress caseload had increased.

Because data is only available up to June 2024, we don’t know how many of the cases which have received an initial decision since Labour entered government have been fully cleared from the overall asylum caseload, and how many are still awaiting further action.

However, data published by the Ministry of Justice shows that as of March 2025 the number of open asylum appeals before the First Tier Tribunal Immigration and Asylum Chamber was 50,976—up from 33,227 at the end of June 2024, shortly before Labour entered government.

This is worth noting, as people whose cases are awaiting further action, like an appeal, may still be entitled to support from the governmen