How Do I Know If My Premises Reaches the 200-Person Threshold?
The 200-person threshold is the most important scope decision under Martyn’s Law. Working out whether your premises reaches it isn’t complicated, but it does require using the right evidence and the right approach.
This page walks through the practical methods the Terrorism (Protection of Premises) Act 2025 accepts, and the one rule that matters most if you’re close to the line.
The Test Is “Reasonable to Expect, From Time to Time”
Before looking at measurement methods, the test to remember:
Is it reasonable to expect 200 or more individuals on your premises from time to time?
“Individuals” counts staff, volunteers, and visitors combined. “From time to time” means regularly, even just once a year if it happens every year. It doesn’t mean “every day” or “on average.”
Your job is to estimate, using evidence, whether your premises crosses 200 individuals at some point.
Evidence-Based Methods the Act Accepts
The Act is deliberately flexible. Any evidence-based method works. In practice, most premises use one or more of these:
1. Historical attendance records
If you keep attendance records, the historical data is the strongest evidence. For schools, this means pupil rolls plus staff plus event attendance. For places of worship, congregation counts for regular services and major events. For hospitality, door counts, till transactions, or bookings. For retail, transaction counts or footfall counters.
Look at the highest regular attendance, not the average. A pub that tops 300 on cup finals but averages 80 is reasonably expecting 300 from time to time.
2. Fire occupancy records
Fire safety documentation typically includes maximum occupancy figures. These are useful as an upper bound. If your fire occupancy is 180, you’re structurally limited below the 200 threshold (unless the fire occupancy was set conservatively and actual attendance can exceed it with staff or spill-over spaces).
3. Ticketing and booking data
For premises that sell tickets or take bookings, the data is direct. The highest regular attendance from ticketed or booked events tells you whether you’re in scope.
4. Footfall counters
Where installed, footfall counters give real-time data. The method is strong but can miss staff counts unless separately tracked. Combine footfall with staff rosters for an accurate picture.
5. Fire safety plans and layout
If you don’t have counted data, the physical layout and capacity of the premises can inform an estimate. How many seats? How many standing spaces? How many rooms occupied simultaneously during peak events?
The Rule If You’re Close to the Line
If different methods give different answers, and your premises sits close to the 200-individual line, the practical recommendation is to lean toward the higher estimate.
Two reasons:
- Regulator risk. If a regulator uses a different method than yours and calculates a higher number, they can find your premises in scope. Enforcement penalties apply to premises that should have prepared and didn’t.
- Marginal cost of preparing. If you assume you’re in scope and prepare Standard Tier procedures, the cost of that preparation is manageable (particularly with a purpose-built platform). If you assume you’re out of scope and you’re wrong, you’ve missed the preparation window.
The downside of preparing when you’re not technically in scope is small. The downside of not preparing when you are in scope is much larger.
What “Regularly” Actually Means
If your premises only reaches 200 for genuinely unforeseen one-off incidents (a bus breaking down outside and 50 extra people walking in), that’s not what “from time to time” is designed to catch.
If your premises reaches 200 regularly, even once a year, that is what it’s designed to catch:
- A village church at Christmas Eve
- A school hall at an annual sports day
- A pub on cup final day
- A community centre at its biggest annual event
- A seasonal hospitality premises at peak trading
If the 200 spike is predictable, it counts.
Still Not Sure?
The fastest way to know is our free Am I in Scope? tool. A handful of questions, a clear answer, no account needed.
If you already know you’re in scope, Get Started with Prova Risk to prepare your public protection procedures, train your staff, and keep the evidence you’ll need if inspected. £399 per year per site.
