How to count your numbers under Martyn's Law

The test the Act actually sets

Premises come into scope when it is reasonable to expect that, from time to time, 200 or more individuals may be present at the same time in connection with the building's use (s.2(2)(c)). Every part of that sentence does a job. It is an expectation, not a headcount: nobody is asking you to stand at the door with a clicker. It is at the same time: annual footfall is irrelevant, and so is a quiet Tuesday. The question is your busiest realistic moment, the single point in your calendar when the most people are inside at once. And it is from time to time: that busy moment does not need to be frequent, only realistic to expect.

From 200 to 799, that expectation puts you in the Standard Tier. From 800, the Enhanced Tier generally begins (s.2(3)(a)), though places of worship and most education settings stay Standard at any size where that is the building's principal use. Under 200, the Act is unlikely to apply to you at all. Our free tier checker walks you through the whole question in about a minute, and our guide to who Martyn's Law applies to covers the boundaries in detail.

Count everyone, not just customers

The figure means every individual on the premises at that moment, and that includes the people working there: employees, contractors and volunteers all count (supplementary document A, para 3 and footnote 2). This is the detail that moves venues across the line. A community hall with 190 wedding guests plus a dozen volunteers running the kitchen and the bar is at 202. So when you picture your busiest moment, count the people behind the bar, in the kitchen, on the door and setting up the next room, not just the ones who came in through the front.

The methods the guidance accepts

"Reasonable to expect" invites an obvious follow-up: reasonable on what basis? The Home Office answered it in a supplementary document published alongside the statutory guidance, which sets out six assessment methods. It is deliberately not prescriptive: the methods are "not prescriptive or exhaustive", they allow for flexibility and judgement, and you choose whichever produces an accurate picture of your premises (supplementary document A, para 2). The six are:

• Safe occupancy for fire safety purposes: the capacity figure you already hold from your fire safety arrangements (paras 13-14).
• Historic attendance data: what your own records show your busiest real days reached (para 15).
• Fixed seating and standing positions: counting the seats and designated standing spots, where that is how your capacity works (para 16).
• Tickets and pre-registration: sales and sign-up numbers, where entry is ticketed (para 17).
• Restrictions: a deliberate limit on admissions that you actually enforce (para 18).
• Other reasonable means: anything else that produces an honest, evidence-based figure (paras 19-20).

For most ordinary venues, the choice comes down to the first two, so they deserve a closer look.

Safe occupancy: the simplest method, and a ceiling

If your venue genuinely fills, the safe-occupancy figure is the easy answer. It already exists, someone else calculated it, and on your busiest nights it is close to the truth. A nightclub that regularly runs at capacity has no better number.

But a safe-occupancy figure is what your building could hold, not what it does. Treat it as an upper bound. The guidance's own worked example makes the point: a nightclub with a safe-occupancy figure of 875 whose attendance records over the past year show a peak of 725 sits, on the evidence, in the Standard Tier rather than the Enhanced (supplementary document A, para 15, example 1). The same logic works at the lower boundary. If your hall could seat 300 but has never seen 150 through the door, the fire figure alone overstates you, and a method grounded in real attendance may describe your premises more accurately.

Historic attendance: what your records actually show

The other everyday method is your own history: till data, door counts, booking records, class registers, event lists. Look across a stretch long enough to catch your genuine peaks, put a number on the busiest realistic moment it contains, and add the staff and volunteers who were working it. For a gym or leisure centre, that is not the membership list; it is the busiest hour, with classes running, the gym floor full and the swim school changing over, plus the team on shift.

The honesty cuts both ways. Historic data can pull an inflated fire figure back down to earth, but it cannot wish away a peak that really happens. If the records show 230 on the busiest night of the year, that is your number, however unrepresentative the other 51 weeks feel.

One big day a year still counts

The phrase that catches venues out is "from time to time". A predictable recurring occasion counts toward the test even if it happens once a year: the pantomime week, finals day, the festival service. Quiet-most-weeks is not the same as out of scope. This deserves its own explanation, so we wrote one: occasional big days and the "from time to time" rule.

Keep a dated note of the number and the method

The supplementary document does not order you to write your assessment down. It does say the Security Industry Authority can require the responsible person to provide information about how the assessment was carried out (supplementary document A, para 4). That is the practical reason to keep a short, dated note: the figure you reached, the method you used, the records you relied on, and the date you did it. If the question ever comes, the answer is one page, written when the facts were fresh.

It is the same position as written documentation generally at Standard Tier: not legally required (statutory guidance, para 7.32), strongly recommended as the way to show your working. And the note has a shelf life. If you refurbish, extend, add a new regular event or change how the building is used, the busiest realistic moment moves, so look again and date the new note. Counting is step two of our step-by-step checklist. MartynsLawPack records the number and the method with each premises.

The short version

• The test is the busiest realistic moment, not the average day and not annual footfall.
• Everyone present counts: customers, staff, contractors and volunteers.
• Pick the assessment method that matches how your venue really runs; the guidance names six and lets you choose.
• Safe occupancy is simple but is a ceiling: best where you genuinely fill.
• Historic peak attendance grounds the number in what actually happens.
• A predictable big occasion counts, even once a year.
• Keep a dated note of the number, the method and the evidence, and refresh it when the building or its use changes.