Custodial Sentences

This Explainer concerns standard determinate custodial sentences, which make up the majority of custodial sentences. There are a few situations when mandatory minimum custodial sentences must be imposed in England and Wales (see our explainer on Mandatory Minimum Sentences). For the most serious offences, the courts must or can impose an indeterminate sentence of life imprisonment (see our explainer on Life Sentences). There are still people serving another form of indeterminate sentence, Imprisonment for Public Protection (see our explainer on Imprisonment for Public Protection), even though this sentence was abolished in 2012.

Determinate sentences differ from indeterminate sentences in that the date when the offender is released on licence is fixed. This used to be at the half-way point of the sentence (unless the person was serving an Extended Sentence), but the release date has become far more complicated. Some people are now released on licence having served two-fifths of their sentence, whilst others continue to serve half or two-thirds of their sentence in prison.

When Can a Standard Custodial Sentence be Imposed?

Section 230(2) of the Sentencing Act 2020 stipulates that a court must not pass a custodial sentence unless it is satisfied that the offence – or the combination of the offence and one or more offences associated with it – was so serious that neither a fine alone nor a community sentence can be justified. This test is often referred to as the ‘custody threshold’.

Guidance by the Sentencing Council came into force on 1 April 2025.¹ Section 2 of the guideline states that, even where the seriousness of the offence indicates that the threshold for a custodial sentence has been passed, ‘a custodial sentence should not be imposed if in all the circumstances of the case it is appropriate to impose a community order’. In other words, if a case satisfies the test in section 203(2) of the Sentencing Act 2020, it is not inevitable that a custodial sentence will be imposed. The guideline states specifically that a custodial sentence should not be imposed on a pregnant person or someone who has given birth within the past 12 months, where the impact on the person or dependents (including unborn children) would be disproportionate to achieving the purposes of sentencing. Previous convictions should not generally be used as the only basis to justify a case passing the custody threshold (see Explainer Previous Convictions [LINK HERE]). In fact, numerous previous convictions might indicate an underlying problem that would be best addressed outside of prison.

One of the main differences between the new guideline and its predecessor is that courts are to ‘step back’ and review whether their provisional sentence fulfils the purposes of sentencing listed in section 57(2) of the Sentencing Act 2020: (a) the punishment of offenders (b) the reduction of crime (including its reduction by deterrence) (c) the reform and rehabilitation of offenders (d) the protection of the public, and (e) the making of reparation by offenders to persons affected by their offences.

The Sentencing Guideline states that research has shown that ‘rehabilitative sentences’ can be more effective in reducing reoffending than a short custodial sentence. In particular, courts should consider whether offenders with an addiction might receive more effective treatment in the community.

Section 231(2) of the Sentencing Act 2020 stipulates that the length of a discretionary custodial sentence must be for the shortest term (not exceeding the permitted maximum) that is commensurate with the seriousness of the offence, or the combination of the offence and one or more offences associated with it. Sentencers are obliged to follow offence-specific guidelines to determine a proportionate term.

The new imposition guideline states that, if the court is considering imposing a sentence of up to 12 months, they should take into account research which shows that short custodial sentences are less effective than other disposals at reducing reoffending. The guideline does, however, recognise that there will be situations where it would be appropriate to impose short custodial sentences rather than a community sentence. Moreover, many offence-specific guidelines recommend custodial terms of less than 12 months.

Where the term is two years or less, a final concern is whether the sentence can be suspended so that the offender can serve their sentence in the community rather than spending some of their sentence in prison (see our explainer Suspended Sentence Order).

Courts do not determine in which prison or prisons a person will serve their sentence.

How many people receive a custodial sentence?

In the 12 months ending September 2024, 76,989 people received an immediate custodial sentence.² This represents 6.7% of all sentences imposed. The proportion of people who received a custodial term varied across the category of offence. In the 12 months ending September 2024, the custody rate for indictable offences was 32.9%.³ For sexual offences, the custody rate was 56.3%, and for robbery it was 54.9%.

At the end of 2024, 85,372 people were in prison.⁴ 37,403 were serving standard determinate sentences (43.8% of the prison population). An additional 8,674 prisoners were serving extended sentences (10.2% of the prison population), a variant of a determinate custodial sentence (see our explainer on Extended Sentences).

How long do people receiving a standard determinate sentence serve in custody?

This used to be an easy question to answer, as all people serving a standard determinate sentence served half of their sentence in prison and the remaining half on licence in the community. Recently, this has become far more complicated, and people can spend two-fifths, one-half, or two-thirds of their sentence in prison with the remainder on licence.

In April 2020, the Government brought in a statutory instrument⁵ that provided that serious violent or sexual offenders, who received a standard determinate sentence of 7 years or more for an offence for which the maximum penalty was life imprisonment, would be required to spend two-thirds of their sentence in custody instead of half. The Police, Crime, Sentencing and Courts Act 2022 enshrined this in legislation but also extended the categories of offences to which the two-thirds period would apply to specified sexual and violent offences where the offender received a standard determinate sentence between 4 and 7 years. (Many people sentenced for such offences might receive an Extended Sentence or Life Imprisonment.) A change was also made in the 2022 Act stipulating that where someone receives a sentence for offences of particular concern, they would become eligible to be released at the two-thirds point as opposed to the half-way point at the discretion of the Parole Board.

This change was significant for prisoners serving standard determinate sentences for these offences, but most prisoners serving standard determinate sentences were still released on licence at the half-way point.

The Criminal Justice Act 2003 (Requisite and Minimum Custodial Periods) Order 2024, which was implemented on 10 September 2024, constitutes a very far-reaching change. The impetus for this change was that the prison estate was running out of space and urgent action was needed to reduce the prison population. Article 3 of the order modifies the application of sections 243A, 244(3)(a) and 264(6)(d) of the Criminal Justice Act 2003, stipulating that applicable individuals will be released from prison having served two-fifths rather than one-half of their sentence. Article 2(2) provides that individuals will be eligible for release on licence having served two-fifths of their sentence if:

• In a case where they received one or more consecutive sentences, the terms of those sentences are in aggregate less than 5 years,
• In a case where they received one of two or more consecutive sentences, the terms of those sentences are in aggregate less than 5 years,
• In any other case, the term of the sentence is less than 5 years.

The Order applies to existing individuals serving qualifying sentences as well as any new sentences imposed after the commencement date. Article 3(6) specifies 54 offences which are excluded from the Order.

1. Sentencing Council (2025) Imposition of Community and Custodial Sentences – Effective from 1 April 2025. https://www.sentencingcouncil.org.uk/overarching-guides/crown-court/item/imposition-of-community-and-custodial-sentences-overarching-guideline/ ↩︎
2. Ministry of Justice (2025) Criminal Justice System Statistics Quarterly: September 2024, Table Q5.1a ↩︎
3. Ministry of Justice (2025) Criminal Justice System Statistics Quarterly: September 2024, Table Q5.2b ↩︎
4. Ministry of Justice (2025) Criminal Justice Management Statistics Quarterly: July to September 2024, Prison Population 31 December 2024, Table 1Q2. ↩︎
5. Release of Prisoners (Alteration of Relevant Proportion of Sentence) Order 2020 ↩︎