When does a criminal conviction become spent?
After a rehabilitation period that depends on the sentence, after which you generally do not have to disclose it — with significant exceptions that catch people out, particularly for certain jobs.
The principle. Legislation in many countries allows most convictions to become spent after a defined period without reoffending, after which the person is treated as if they had not been convicted for most purposes. The aim is to allow people to move on, which the evidence supports as reducing reoffending.
How the period works, broadly: it runs from the end of the sentence, not the date of conviction; longer sentences carry longer periods; sentences above a defined length never become spent; and periods are shorter for people convicted as under-18s.
What being spent means: you generally do not have to disclose it when asked; an employer cannot lawfully refuse you on that basis for most roles; and it does not appear on a basic criminal record check.
The exceptions, which matter enormously:
Excepted roles. For work involving children or vulnerable adults, and for certain professions including law, healthcare, finance and security, standard and enhanced checks apply. These can reveal spent convictions, subject to filtering rules that remove some older and minor matters after defined periods.
Enhanced checks can also include non-conviction information that a police force reasonably believes is relevant, which surprises people.
Other contexts where disclosure may still be required: insurance, where non-disclosure can void a policy; visa applications, where other countries apply their own rules and frequently do not recognise your rehabilitation periods at all; adoption and fostering; and some licensing.
Cautions, warnings and fixed penalties are treated differently from convictions and generally become spent immediately or very quickly, though simple cautions can still appear on enhanced checks for a period.
What to do: check the specific rules for the role or purpose rather than assuming; use official guidance or a specialist advice charity to work out your own position; and answer honestly what is actually asked — undisclosed convictions discovered later are treated far more seriously than the original matter.
UK-focused. General information, not legal advice.