Martyn's Law is expected to come into force in spring 2027, with the exact date confirmed ahead of commencement. For premises in scope, the obligations depend almost entirely on two capacity figures.
THE THRESHOLDS
Standard tier applies where between 200 and 799 people may be present at the same time at the busiest point. Enhanced tier applies at 800 or more.
STANDARD TIER
The responsible person must notify the SIA of their identity, and put in place public protection procedures covering evacuation, invacuation, lockdown and communication, so far as is reasonably practicable.
ENHANCED TIER
The same notification and the same four procedures, plus public protection measures covering monitoring, movement control, physical security and information security. Enhanced tier also carries a documentation burden the standard tier does not: procedures and measures must be documented, their effectiveness assessed, and the documentation submitted to the SIA.
THE EXCEPTION WORTH KNOWING
Premises used for childcare, for primary, secondary or further education, or as places of worship remain in the standard tier regardless of whether capacity exceeds 800.
WHERE THE REGULATOR HAS GOT TO
The SIA opened a consultation on its draft section 12 statutory guidance on 15 April 2026, covering its regulatory approach, how it will provide guidance to premises, its information-sharing powers, inspection procedures and enforcement mechanisms. That consultation closed on Friday 12 June at 11:59pm. Final guidance is to be published before the Act comes into force.
WHAT IT MEANS FOR OPERATORS
The window for influencing how this is policed has closed. What remains open is preparation, and the implementation period is at least twenty-four months from Royal Assent on 3 April 2025.
The practical work is unglamorous and worth starting from the capacity figure rather than the security philosophy: establish the busiest-point number honestly, confirm which tier that puts each site in, identify the responsible person by name, and for enhanced-tier sites recognise that documentation is not administrative overhead but a submitted deliverable.
Sites sitting close to 800 deserve early attention, because a capacity assessment that drifts upward moves a venue between two materially different regimes.
