Stay Informed on Prison Law and Justice Reform

Sentencing Reform: “33% Minimum Release” for Standard Determinate Sentences (SDS)

Overview

The UK Government is progressing a major change to how fixed-term prison sentences are administered. Under proposed reforms in the Sentencing Bill, many people serving a Standard Determinate Sentence (SDS) — the most common type of fixed-term custodial sentence — will now have a minimum custodial release point set at one-third (33%) of their sentence length if they engage constructively while inside prison.
This represents a substantial reform of the old system, where release was often automatic at 40% or 50% of the sentence for standard determinate sentences.

What’s Changing?

Under the Progression Model in the Sentencing Bill:
People serving an SDS will not be automatically released at a fixed halfway or 40% point — instead, the minimum release point will be one-third of the sentence provided the prisoner behaves appropriately.
For more serious SDS offenders who previously had a higher automatic release point (like 67%), the minimum has been set at 50%.
Release eligibility will be linked to conduct and engagement in prison, and disciplinary breaches may delay release through additional custodial days imposed by adjudicators.
After release, there will be a structured period of intensive community supervision and licence conditions, including tagging, curfews, and movement restrictions, aimed at improving public safety and support.
In other words, the system rewards positive behaviour and progress inside custody, while maintaining public protection through enforceable supervision on licence after release.

Why This Reform?

The changes stem from the urgent need to address ongoing prison capacity pressures in England and Wales — a challenge highlighted in the Government’s criminal justice strategy and Independent Sentencing Review.
The reforms aim to:
Simplify and standardise release points across standard determinate sentences
Encourage constructive engagement with rehabilitation and behaviour programmes
Maintain public confidence in sentencing outcomes
Reduce confusion among victims and families about when release might occur

Impact for Prisoners & Families

For many people currently serving a standard determinate sentence, this could mean:
Release earlier than previously expected if they demonstrate good conduct;
A structured supervision period immediately after release;
Greater emphasis on behaviours and activities that support reintegration.
However, for serious violent or sexual offenders and high-risk individuals, higher minimum custodial thresholds and specific exclusions remain in place.

Status of the Law

The Sentencing Bill is still passing through Parliament and has not yet become law. Many of its provisions — including the 33% minimum release point for SDS — are expected to take effect in 2026 once the Bill receives Royal Assent and is implemented.

Gateway PLS Commentary

At Gateway Prisoner Legal Services, we are monitoring these changes closely. They have significant implications for release planning, recall eligibility, and licence supervision for those we represent. Once enacted, these reforms may affect legal advice on sentence calculation, risk management, recall challenges, and human rights considerations.
If you or a loved one is serving a determinate sentence and have questions about how the new rules might affect release dates, eligibility for early release, or licence conditions, our specialist legal team can help — contact us for an assessment.