Prison Sentences of 12 Months or Less
Research on the effectiveness and impact of sentences, orders, and requirements.
Last updated: May 2026
Summary
This Bulletin summarises research on the effectiveness of prison sentences of 12 months or less (often referred to as ‘short’ prison sentences). Effectiveness is considered in terms of fulfilling the five main aims of sentencing, as well as cost-effectiveness.
Although research on the effectiveness of different sentencing options is limited, there is sufficient research on short prison sentences to draw conclusions about their effectiveness. While short prison sentences are punitive, they are associated with the highest re-offending rates out of all primary disposals, they hinder rehabilitation after release from prison, and they are significantly more expensive than community-based sentences.
The Sentencing Act 2026 will likely limit the use of short prison sentences in favour of suspended sentences of imprisonment, and research will need to establish the effect of this reform on crime reduction, re-offending, and rehabilitation.
Introduction
Prison sentences of 12 months or less (from here on referred to as ‘short’ prison sentences) are the most commonly imposed custodial sentences in England and Wales. At the same time, there is concern among criminal justice stakeholders and legislators that they are less effective than other types of sentences. In fact, in an attempt to reduce prison overcrowding, reforms in the recent Sentencing Act 2026 are expected to significantly reduce the use of short prison sentences in favour of Suspended Sentence Orders.
This Bulletin reviews research on the use and effectiveness of prison sentences of 12 months or less in England & Wales. This review focuses on studies published in English between 2015-2026.
Short prison sentences are the most commonly imposed prison sentences.
In 2024, only 4% of all imposed sentences were prison sentences of 12 months or less. However, statistics reveal that most prison sentences (62%) were short (Sentencing Academy, 2025). In total, 49,647 such short sentences were imposed in 2024, and 73% were below six months (see Figure 1). More than 40% of short sentences were imposed for shoplifting, assault of an emergency worker, common assault and battery, breach of a restraining order, and non-domestic burglary.1
Figure 1: Breakdown of Short Prison Sentence Lengths, 2024
Data calculated from: Ministry of Justice (2025), Criminal Justice Statistics Quarterly: December 2024, published 15th of May. Outcomes by offence data tool, Table 2, percentages rounded.
However, these trends are likely to change. In September 2025, the Sentencing Council issued new guidelines, suggesting that:
‘If the court is considering an immediate custodial sentence of up to 12 months, it should take into account that research suggests that custodial sentences of up to 12 months are less effective than other disposals at reducing reoffending and can lead to negative outcomes.’ (Sentencing Council, 2025)
The Sentencing Act 2026 has introduced a legal presumption to suspend all custodial sentences of 12 months or less, unless exceptions apply. The use of short prison sentences is thus expected to decline in the coming years.
Short prison sentences are not as effective as other sentences.
Stakeholders across the criminal justice system have long been concerned that short prison sentences are less effective than other types of sentences in fulfilling the five purposes of sentencing (punishment of offenders; reduction of crime (including by deterrence); reform and rehabilitation; protection of the public; reparation). As custodial sentences are commonly considered to be punitive, the punitive elements of short prison sentences will not be discussed in this Bulletin, which will instead focus on re-offending, crime reduction, and rehabilitation.
In 2001, the Halliday review suggested that short prison sentences were less effective at promoting rehabilitation than other sentences (Halliday, 2001). Indeed, short prison sentences have higher re-offending rates than other sentences, create challenges that render it more difficult for someone to successfully rehabilitate after release from prison, and are less cost-effective than other sentences. The next sections examine each of these in more depth.
Re-offending
Evidence reveals that short custodial sentences are less effective at reducing reoffending than other disposals (Gormley et al., 2022; Hamilton, 2021; Mutebi & Brown, 2023.2
Table 1 below shows the percentage of people within each sentence group who re-offended (i.e. were convicted or received a caution for a new offence) during a one-year period, as well as the average number of re-offences per sentence group. As the table reveals, people who serve a prison sentence have a higher re-offending rate (40%) than those sentenced to Community Orders (COs) (38%) or Suspended Sentence Orders (SSO) with requirements (25%). Similarly, people who serve a prison sentence commit a higher average number of re-offences (6.3) than those who received a CO (4.1) or an SSO (4.5). The re-offending rates and average number of re-offences are even higher for the shortest custodial sentences (six months or below), with a re-offending rate of 63% and an average number of 7.3 re-offences.
Table 1: Re-offending Rates by Principal Sentence, 2023
| Sentence Type | Proportion of People who Re-offended | Average Number of Re-Offences |
|---|---|---|
| All disposals | 27% | 4.5 |
| All custodial sentences | 40% | 6.3 |
| Custodial Sentences ≤ 6 months | 63% | 7.6 |
| Custodial Sentences < 12 months | 60% | 7.3 |
| Suspended Sentence Orders (with requirements) | 25% | 4.5 |
| Community Orders | 38% | 4.1 |
| Fines | 23% | 4.0 |
| Discharges | 27% | 4.9 |
Research by the Ministry of Justice (MoJ) found that the risk of re-offending remains higher for people who served short prison sentences well beyond the common one-year follow-up period. Using Police National Computer data, the study examined re-offending for a cohort of convicted individuals between 2000-2018, concluding that people who had served shorter prison sentences continued to have a higher risk of re-offending compared to people serving other sentences (Uhrig & Atherton, 2020).
An MoJ study using propensity score matching found an association between short prison sentences and higher rates of re-offending. Controlling for over 150 variables including the nature and seriousness of the offence, previous convictions, employment status, substance use, and family relationships, the study found that short prison sentences were associated with higher reoffending rates compared to COs and SSOs for matched groups of people (Eaton & Mews, 2019). A second MoJ study also using propensity score matching reached similar conclusions (Chalam-Judge & Martin, 2024).
For certain groups, short prison sentences are associated with even higher rates of re-offending. For example, one study using propensity score matching found that re-offending rates for people with ‘significant psychiatric problems’ were 11% higher for short prison sentences compared to Community Orders (Hillier and Mews, 2018). The same study found that community-based sentences were more effective at reducing re-offending for people with a high number of previous offences. For people with more than 50 previous convictions, a short prison sentence was associated with a 36% higher risk of re-offending compared to people who were given a community-based sentence (Hillier and Mews, 2018).
Why do short prison sentences have higher re-offending rates than longer prison sentences and community-based sentences?
One explanation for the high re-offending rates after short prison sentences is that these sentences are usually imposed for ‘low harm, high volume’ offences (Uhrig & Atherton, 2020). According to this line of reasoning, people are less likely to commit serious offences that lead to longer prison sentences, and more likely to commit less serious offences – such as shoplifting – more often, which is why re-offending rates for short prison sentences are higher. However, this argument does not account for the fact that community-based sentences, which are usually imposed for less serious offences – are also associated with lower re-offending rates than short prison sentences. Therefore, there must be something about the nature of short prison sentences that contributes to them being associated with the highest re-offending rates.
Unlike community-based sentences, short prison sentences disrupt employment, any medical or psychiatric treatment, and family ties. The loss of income can lead to further problems, such as losing their home or accruing debt, while imprisonment might result in a loss of benefits. All such factors – employment, treatment, stable housing, family ties – are associated with lower risks of re-offending post-imprisonment (Mutebi & Brown, 2023).
At the same time, people who receive short prison sentences are usually not in prison long enough to receive any rehabilitative programming, such as skills training, mental health or substance use treatment – all of which support a person’s desistance post-release (Cracknell, 2023). At this time, prisons across England & Wales are overcrowded and there are limited opportunities for people in prison to engage in ‘purposeful activity’. In addition, the number of people in prison with acute mental health issues and substance use needs is rising (Justice and Home Affairs Committee, 2025).
Moreover, short prison sentences have a disproportionate impact on certain groups. One qualitative study examined the impact of short prison sentences on mothers (n=17) and their children (n=50). It concluded that short prison sentences are particularly disruptive for families, with mothers struggling to secure housing and financial stability post-release. This, in turn, led to evictions, further disrupting their children’s lives (Baldwin & Epstein, 2017).
Crime Reduction (Deterrence)
One of the principal aims of sentencing is to reduce crime. Whether crime reduction was achieved by a specific sentence is often measured by analysing re-offending data, as noted earlier. By this measure, short prison sentences are ineffective at reducing crime, as they are associated with higher re-offending rates. A second way of measuring crime reduction is by assessing whether short sentences are effective at ensuring individual and general deterrence from crime.
Research on deterrence and short prison sentences is generally limited. A systemic research review assessing research on the deterrent effect of a prison sentence concluded that deterrence ‘looks weak or effectively non-existent’ (Roodman, 2017, p.129). Imprisonment obviously has an incapacitating effect for the person who is in prison (individual deterrence), as they are no longer able to commit further offences within the community. However, many studies have found that prisons can have criminogenic effects, both because of violence inside prisons, and because of ‘criminal associations’ that people might form during or after their imprisonment (Damm & Gorinas, 2020; Gormley et al., 2022; Kleck & Sever, 2017). Thus, while research on the effect of short prison sentences on deterrence remains sparse, there is some evidence suggesting that they may encourage criminogenic behaviour.
Rehabilitation
Like crime reduction, rehabilitation – one of the aims of sentencing – is often assessed by measuring re-offending. However, a second important measure is a person’s re-integration, including their economic, social, and political re-integration, after they are released from prison. In fact, a person’s rehabilitation is inextricably linked to their risk of re-offending, as ‘the effect of incarceration on recidivism depends on not only what goes on within the prison walls but also the treatment of former prisoners in the larger society’ (Loeffler & Nagin, 2022).
Research by the MoJ found that re-integration is more difficult for people who received short prison sentences, compared to those who received community-based sentences (Mutebi & Brown, 2023). As shown in Table 2, our analysis of MoJ data reveals that employment rates for people who received prisons sentences of 12 months or less are much lower than for those who received a community-based sentence (MoJ, 2026a; 2026b).
Table 2: Employment rates 6 months post-release/sentence end, May 2024-March 2025
| Sentence Type | Employment Rate |
|---|---|
| Custodial Sentences | |
| —— Less than or equal to 6 months | 12.9% |
| —— Less than 12 months | 13.4% |
| —— 12 months or above | 29.0% |
| Community-based sentence (CO or SSO) | 35.0% |
Equally, data reveals that a higher proportion of people who received a short prison sentence are homeless 3-months post-release, compared to those who received a community-based disposal. For someone serving a prison sentence of 6 months or less, the risk of being homeless post-release is more than three times higher than for someone who received a community-based sentence.
Table 3: Homelessness rates 3 months post-release/sentence end, May 2024-March 2025
| Sentence Type | Homelessness Rate |
|---|---|
| Custodial Sentences | |
| —— Less than or equal to 6 months | 17.9% |
| —— Less than 12 months | 15.2% |
| —— 12 months or above | 3.9% |
| Community-based sentence (CO or SSO) | 5.8% |
Although this data alone does not control for variables such as pre-conviction employment or housing status, a prison sentence is often a barrier to finding employment or housing. This in turn makes successful re-integration for a previously imprisoned person significantly more difficult than for someone who received a community-based sentence (PRT, 2022; Sentencing Council, 2025).
Cost
Though cost is not one of the main considerations in sentencing, it is nonetheless an important consideration for legislators. Researchers have suggested that short prison sentences are less cost-effective than community-based sanctions (Curzon & Roberts, 2021; Gormley et al., 2022). In 2023/24, the annual cost per prisoner was over £53,000 (MoJ, 2025b), whereas the average cost per Suspended Sentence Order or Community Order was £3,150 (Timpson, 2025). In other words, a 12-month prison sentence costs over 16 times more than a community order of the same duration. In addition, e-offending costs the taxpayer around £23 billion per year (Richards, 2025) – costs that may be reduced if the use of short prison sentences were reduced.
Data Limitations & Research Priorities
Unlike research on the effectiveness on other disposals, there is much research available on the effectiveness of prison sentences of 12 months or less, particularly with regard to the high re-offending rates associated with them. However, there is little evidence on whether short prison sentences are effective at deterring people from offending. Moreover, we know less about how differences in gender, ethnicity, or local service capacity influence outcomes for people who receive short prison sentences compared to those who receive community-based sentences. Lastly, the MoJ measures re-offending within one year post release or sentence end, which obscures our understanding of the long-term impacts of different sentences. Research examining re-offending for a longer period as well as research examining the impact of short prison sentences on different groups of people would therefore improve our understanding of how, when, and for whom short prison sentences might be particularly ineffective.
Conclusion
Evidence on the effectiveness of prison sentences of 12 months or less suggests that they are associated with higher re-offending rates, may be criminogenic, hinder rehabilitation, and are significantly more expensive than community-based sanctions. Changes in the Sentencing Act 2026 will likely reduce the number of short prison sentences imposed in favour of Suspended Sentence Orders. However, the success of these changes will depend on a well-resourced and staffed probation service, which will have to cope with the increasing number of people requiring supervision.
This Bulletin is part of a series on the effectiveness of sentencing in England & Wales. Other Effectiveness Bulletins can be found here.
For further information, contact Annalena Wolcke at a.wolcke@sentencingacademy.org.uk
References
- Baldwin, L. and Epstein, R. (2017) Short but not sweet: A study of the impact of short custodial sentences on mothers & their children. De Montfort University. Available at: https://www.nicco.org.uk/userfiles/downloads/5bc45012612b4-short-but-not-sweet.pdf.
- Chalam-Judge, R. and Martin, E. (2024) Evaluation Report: Impact of being sentenced with a community sentence treatment requirement (CSTR) on proven reoffending. Ministry of Justice (MoJ). Available at: https://www.gov.uk/government/publications/impact-of-being-sentenced-with-a-community-sentence-treatment-requirement-cstr-on-proven-reoffending.
- Cracknell, M. (2023) ‘Invisible men: Short prison sentences and the pains of invisibility and insignificance’, The Howard Journal of Crime and Justice, 62(3), pp. 341–356. Available at: https://doi.org/10.1111/hojo.12517.
- Curzon, E. and Roberts, J. (2021) The Suspended Sentence Order in England and Wales. Sentencing Academy. Available at: https://www.sentencingacademy.org.uk/the-suspended-sentence-order-in-england-and-wales-september-2021/.
- Damm, A.P. and Gorinas, C. (2020) ‘Prison as a Criminal School: Peer Effects and Criminal Learning behind Bars’, The Journal of Law and Economics, 63(1), pp. 149–180. Available at: https://doi.org/10.1086/706820.
- Eaton, G. and Mews, A. (2019) Impact of short custodial sentences, community orders and suspended sentence orders on reoffending. Ministry of Justice. Available at: https://www.gov.uk/government/publications/impact-of-short-custodial-sentences-community-orders-and-suspended-sentence-orders-on-reoffending.
- Gormley, J., Hamilton, M. and Belton, I. (2022) The Effectiveness of Sentencing Options on Reoffending. Sentencing Council. Available at: https://sentencingcouncil.org.uk/media/rdzfopqp/effectiveness-of-sentencing-options-review-final.pdf.
- Halliday, J. (2001) Making Punishment Work: Report of a review of the sentencing framework for England and Wales. National Archives.
- Hamilton, M. (2021) The Effectiveness of Sentencing Options. Sentencing Academy. Available at: https://www.sentencingacademy.org.uk/research-articles/the-effectiveness-of-sentencing-options/.
- Hillier, J. and Mews, A. (2018) Do offender characteristics affect the impact of short custodial sentences and court orders on reoffending? Ministry of Justice (MoJ). Available at: https://www.gov.uk/government/publications/do-offender-characteristics-affect-the-impact-of-short-custodial-sentences-and-court-orders-on-reoffending.
- Justice and Home Affairs Committee (2025) Better prisons: less crime. House of Lords. Available at: https://committees.parliament.uk/committee/519/justice-and-home-affairs-committee/news/208335/prisons-need-to-have-reducing-reoffending-as-their-core-purpose-says-lords-committee/.
- Kleck, G. and Sever, B. (2017) Punishment and Crime: The Limits of Punitive Crime Control. New York: Routledge. Available at: https://doi.org/10.4324/9781315142258.
- Loeffler, C. and Nagin, D. (2022) ‘The Impact of Incarceration on Recidivism’, Annual Review of Criminology, 5(1). Available at: https://doi.org/10.1146/annurev-criminol-030920-112506.
- Lord Timpson (2025) ‘Probation: Costs. Question for Ministry of Justice’. Available at: https://questions-statements.parliament.uk/written-questions/detail/2025-04-25/hl6914.
- MoJ (2026a) ‘Offender employment outcomes, update to March 2025. Employment at 6 months post release from custody data tables.’ Available at: https://assets.publishing.service.gov.uk/media/688a4189e1a850d72c40927d/Employment_at_6_months_post_release.xlsx.
- MoJ (2026b) ‘Offender employment outcomes, update to March 2025. Employment at 6 months post community disposal data tables’. Available at: https://assets.publishing.service.gov.uk/media/688a41af76f68cc8414d5bff/Employment_at_6_months_post_disposal.xlsx.
- MoJ (2026c) Offender accommodation outcomes, update to March 2025. Settled accommodation at 3 months post release from custody data tables, GOV.UK. Available at: https://assets.publishing.service.gov.uk/media/688a01ae8b3a37b63e73900c/Accommodation_at_3_months_post_release_from_custody.xlsx.
- MoJ (2026d) Offender accommodation outcomes, update to March 2025. Settled accommodation at 3 months post community disposal data tables, GOV.UK. Available at: https://assets.publishing.service.gov.uk/media/688a01d076f68cc8414d5b7b/Accommodation_at_3_months_post_community_disposal.xlsx.
- MoJ (2025a) Proven reoffending statistics: July and September 2023, GOV.UK. Available at: https://www.gov.uk/government/statistics/proven-reoffending-statistics-july-and-september-2023.
- MoJ (2025b) Prison performance data 2023 to 2024. Costs per place and costs per prisoner by individual prison, GOV.UK. Available at: https://www.gov.uk/government/publications/prison-performance-data-2023-to-2024.
- MoJ (2023) Community Performance Annual, update to March 2023, GOV.UK. Available at: https://www.gov.uk/government/statistics/community-performance-annual-update-to-march-2023/community-performance-annual-update-to-march-2023.
- Mutebi, N. and Brown, R. (2023) ‘The use of short prison sentences in England and Wales’, POST (UK Parliament) (52). Available at: https://post.parliament.uk/research-briefings/post-pb-0052/.
- PRT (Prison Reform Trust) (2022) Prison: the facts—Summer 2022. Available at: https://prisonreformtrust.org.uk/publication/prison-the-facts-summer-2022/.
- Richards, J. (2025) ‘Reoffenders. Question for Ministry of Justice’. Available at: https://questions-statements.parliament.uk/written-questions/detail/2025-10-31/87187/.
- Roodman, D. (2017) The impacts of incarceration on crime. Open Philanthropy Project. Available at: https://doi.org/10.48550/arXiv.2007.10268.
- Sentencing Academy (2024) Who’s in Prison & What’s the Purpose of Imprisonment? Sentencing Hub: Sentencing Academy. Available at: https://sentencinghub.sentencingacademy.org.uk/public-perceptions/whos-in-prison-whats-the-purpose-of-imprisonment/.
- Sentencing Academy (2025) ‘A Legislative Presumption Against the Use of Short Prison Sentences.’ Available at: https://www.sentencingacademy.org.uk/a-legislative-presumption-against-the-use-of-short-prison-sentences/.
- Sentencing Act 2026. Available at: https://bills.parliament.uk/bills/4012.
- Sentencing Council (2015) Imposition of community and custodial sentences, Sentencing Council. Available at: https://sentencingcouncil.org.uk/guidelines/imposition-of-community-and-custodial-sentences/.
- Uhrig, N. and Atherton, K. (2020) Reoffending Following Custodial Sentences or Community Orders, by Offence Seriousness and Offender Characteristics, 2000–2018. Ministry of Justice Analytical Series. Available at: https://assets.publishing.service.gov.uk/media/5f688b18e90e072b9bd0a79c/reoffending-custodial-sentences-community-orders-research-report.pdf.
- Data calculated from: Ministry of Justice (2025), Criminal Justice Statistics Quarterly: December 2024, published 15th of May. Outcomes by offence data tool, Table 2. https://www.gov.uk/government/statistics/criminal-justice-system-statistics-quarterly-december-2024. ↩︎
- Data calculated from: Ministry of Justice (2025), Proven reoffending tables (3 monthly), October 2023 to December 2023. Tables A4A, C1a and C2a. https://www.gov.uk/government/statistics/proven-reoffending-statistics-october-to-december-2023. ↩︎