If you run a fete, a market or a small food festival and someone has told you that Martyn's Law starts biting at 200 people, they have given you the wrong number. For events the threshold is 800, and even then it only applies if you actually check people in at a defined and secure perimeter.
The 200 figure is real, but it belongs to something else. It is the bottom of the standard tier for premises, meaning buildings. The Security Industry Authority, which will regulate the law, puts it plainly in its own guidance: premises where between 200 and 799 people may be present at the same time, at the busiest times, will be in the standard tier. That is a village hall. It is not your fete on the recreation ground.
What the law actually says about events
The Terrorism (Protection of Premises) Act 2025, known as Martyn's Law, received Royal Assent on 3 April 2025. It is not yet in force. The Home Office is explicit that its requirements have not been commenced and do not need to be complied with until they are brought into force by regulations. The SIA says it expects that to happen in spring 2027, and that it will confirm the exact date beforehand. Nobody has named a day, so treat any consultant who quotes you one as guessing.
For a qualifying event, three things have to be true together.
- It should be reasonable to expect that 800 or more individuals will be present at the same time, at some point during the event. Staff count towards that figure, and the threshold does not have to be met for the whole event. The Home Office's own worked example is a day festival with 500 people on site until 6pm and 1,000 or more expected later, which qualifies.
- There must be an entry check: tickets, a guest list, a paid entry that is actually verified.
- There must be a secure perimeter. The guidance is direct about why: for entry controls to be in place, the event will need a well defined and secure perimeter so that the entry check will be meaningful.
Two consequences follow, and both cut in favour of small organisers.
A suggested donation is not an entry check. The guidance says so specifically: a suggested entry charge or donation does not satisfy the criterion, because it is not a measure to check that someone has paid. So the bucket at the gate of your fete does not put you in scope.
Open areas with no entry checks are outside the Act altogether. Pavements, towpaths and open roads are named. A free market on a high street is not in scope however busy it gets, unless it sits in the immediate vicinity of a qualifying event.
The sting, for anyone who does cross 800
Here is the part that gets under-reported, and it is the reverse of the reassurance above. An organiser who does cross 800 with wristbands on a fenced field is not put in the gentle standard tier. The SIA is unambiguous: qualifying events have the same requirements as enhanced tier premises.
That means documenting your public protection procedures, assessing how they reduce risk, and sending that document to the regulator. So the practical picture is a cliff rather than a slope. Below the line, nothing. Above it, the same paperwork as an arena.
The clock starts when you announce, not when you open
This is the detail most likely to catch a volunteer committee out. The Terrorism (Protection of Premises) (Notification Requirements) Regulations 2026 were made on 9 July 2026 and laid before Parliament on 14 July. They do not set their own date; they switch on when the relevant section of the Act does.
When they do, premises get three months to notify the regulator. Events get 14 days from first publicising the event. And publicising is defined broadly: public websites or social media, physical or digital promotional materials, posters, signage or notices, and emails to a customer mailing list.
In other words, the moment you put next year's date on Facebook, a two-week clock starts. Not when the gates open.
You can hand the paperwork to someone else, but not the responsibility. The guidance says a responsible person may authorise an employee, agent or consultant to submit a notification, but legal responsibility cannot be delegated. Knowingly or recklessly providing false or misleading information in a notification is a criminal offence under section 25 of the Act.
What the regulator says it is trying to do
Laura Gibb, Executive Director for Martyn's Law at the Security Industry Authority, has set out the intended posture.
Martyn's Law was consciously designed to improve standards and consistency but not place an excessive burden on those who fall into scope. The focus is on what is 'appropriate' and 'reasonably practicable' for each individual premises or event. This means there is no 'one size fits all'.
She has also said the regulator particularly wants to hear from smaller organisers.
We are particularly interested in those from places of worship, volunteer-run community centres, festivals and one-off events.
The SIA consulted on draft guidance between 15 April and 12 June 2026 and says it will publish the final version, with a consultation report, in autumn 2026. It also says it will typically give at least 72 hours' notice before an on-site inspection, though it can ask a court for a warrant to enter without notice in some circumstances.
What to do now
- Count honestly, including staff and volunteers. Will 800 people ever be on site at once, even for one hour?
- Check whether you really have entry control. A gate you can walk around is not a secure perimeter, and a donation bucket is not a check.
- If both are yes, plan for enhanced tier duties, not the lighter ones, and wait for the SIA's final guidance in the autumn.
- Diarise the 14 days. Whoever posts next year's date needs to know it starts a clock.
If you are earlier in the process than any of this, our guide to booking your first market stall covers the ground floor, and public liability insurance is the cover organisers will actually ask you for.
