UK OSA Sections 9 and 10 - Illegal content risk assessment and safety duties (regulated user-to-user services)
Operate proportionate systems to prevent users encountering priority illegal content and minimise the time any illegal content remains on the service
Where this comes from
Provision: Sections 9 and 10 - Illegal content risk assessment and safety duties (regulated user-to-user services)
Instrument: UK Online Safety Act 2023
Citation: Online Safety Act 2023, c. 50, ss 9 and 10 (including s 10(3A)-(3B), inserted 29 June 2026); s 59 (meaning of illegal content and priority offence); Sch 5 (terrorism offences), Sch 6 (child sexual exploitation and abuse offences), Sch 7 (other priority offences); s 66 (separate duty to report CSEA content to the NCA)
Text version: Online Safety Act 2023 c. 50, revised text as displayed on legislation.gov.uk on 2026-09-21 ('up to date with all changes known to be in force on or before 21 September 2026'), including the amendments made by the Crime and Policing Act 2026 in force from 29 June 2026 (S.I. 2026/689) and s 66 in force from 7 April 2026 (S.I. 2026/262). The as-enacted text is superseded.
Who it applies to
User-to-user content surface — any one of these:
- Service allows user-generated content
- Service enables direct messaging between users
What engineering work it implies
Sample acceptance criteria Landfall generates for this obligation:
- Content can be flagged (by users and/or automated classifiers) and enters a moderation queue
- Moderation decisions (allow / remove / restrict / escalate) are recorded with reviewer, reason, and timestamp
- Priority/expedited handling exists for illegal content and child-safety categories
- Affected users are notified of moderation actions with a stated reason and appeal path
- Repeat-offender and re-upload prevention is in place where required
Questions people ask
- Does UK OSA Sections 9 and 10 - Illegal content risk assessment and safety duties… apply to my service?
- It applies when at least one of: Service allows user-generated content; Service enables direct messaging between users.
- From when does this apply?
- UK OSA Sections 9 and 10 - Illegal content risk assessment and safety duties… applies from 10 January 2024. Its current status is: in force.
Find out whether this one lands on you
Landfall's pre-scan answers the applicability question above for your product in minutes, then turns every obligation that applies into traceable engineering tickets with a citation chain your auditors can follow.
Not legal advice. Landfall maps regulatory obligations to engineering work for planning purposes. Its verdicts are not legal advice and create no attorney-client relationship — verify with qualified counsel before relying on them.