SDS33
Shorthand for the release point that replaces SDS40 from 1 October 2026: most people serving a standard determinate sentence are automatically released after one-third of the custodial term rather than 40%. Sentences currently releasing at two-thirds move to one-half.
Related Terms
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Progression Model
The three-stage structure the Sentencing Act 2026 gives standard determinate sentences: roughly one-third in custody, one-third in the community under intensive supervision, and one-third 'at risk' with no active supervision but still liable to recall. It starts on 1 October 2026. Also called the earned progression model, though release remains automatic at the conditional release date.
SDS40
Scheme where prisoners serve 40% instead of 50% of standard determinate sentences in prison, with extended community supervision. Replaced ECSL in September 2024. The Sentencing Act 2026 replaces it in turn: from 1 October 2026 the automatic release point for most standard determinate sentences moves to one-third, sometimes called SDS33.
Standard Determinate Sentence
A fixed-term prison sentence with automatic release at a set point. Currently release is at 40% of the sentence, but under the Sentencing Act 2026 this will change to one-third for many cases. This is the most common type of prison sentence.