How do I count my venue's capacity for Martyn's Law?

Capacity is the first question and often the only difficult one. It decides whether Martyn's Law applies to you at all, and if it does, which tier you are in.

The good news is that the standard is lower than most people expect. You are not being asked to commission a survey. You are being asked to use evidence you already hold, and to write down which evidence you used.

The thresholds

People who could reasonably be present at once	Where you sit
Fewer than 200	Out of scope
200 to 799	Standard tier
800 or more	Enhanced tier

One important exception: places of worship, childcare premises and educational premises are always standard tier, whatever their capacity. If that is you, the capacity question only decides whether you are in scope at all, not which tier — see standard tier vs enhanced tier.

The test: who could reasonably be there at once

The figure that matters is the greatest number of individuals who could reasonably be expected to be present at the same time.

Two parts of that sentence do the work.

"Individuals" means everyone, not just the public. Staff, volunteers, contractors, performers, caterers, the person running the bar and the two people setting out chairs all count. For a volunteer-run hall this is frequently what moves a venue from 190 to over 200.

"Could reasonably be expected" means your busiest realistic day, not an average one and not a theoretical maximum. The Christmas fair counts. The annual general meeting counts. A hypothetical scenario where every seat is filled and every aisle is packed does not, if that has never happened and could not.

The six ways to evidence it

The Home Office accepts any of the following, and any other method you can reasonably justify:

1. Fire safety occupancy figures. The number you already work to for fire safety purposes. For most venues this is the easiest and strongest answer, because it is a figure you already rely on for another legal duty.
2. Historical attendance records. Door counts, register figures, past event attendance. Useful if you have several years of them.
3. Counts of fixed seating or standing positions. Pews, fixed seats, a laid-out room at a known spacing.
4. Ticket or registration sales. Where entry is ticketed, the number you sell is direct evidence.
5. Limits set by a licence or other restriction. A premises licence condition capping numbers is evidence of the ceiling.
6. Any other reasonable method you can justify. Room area against an occupancy factor, for instance — as long as you can explain it.

You do not need all six. You need one you can stand behind, plus a note of what you used.

Worked example: a village hall

St Peter's Hall has a main room and a small committee room.

• The fire risk assessment gives a maximum occupancy of 220 for the main room.
• The busiest event of the year is the Christmas fair, which historically draws about 160 visitors.
• On fair day there are also 12 volunteers, 4 stallholders and 2 caterers.

The busiest realistic figure is 160 + 18 = 178, but the fire safety occupancy figure is 220.

The hall is in scope. The fire figure is the number they already work to, and they cannot both rely on it for fire safety and disown it here. Their capacity record reads:

Capacity 220. Method: fire safety occupancy figure from the fire risk assessment dated March 2026, main room. Peak observed attendance 178 (Christmas fair, December 2025).

That is the whole exercise. It took ten minutes and it is defensible.

Worked example: a church with a hall

Trinity Church has a nave seating 260 and a separate hall behind it that seats 90.

The two are on the same site and used together at festivals. If both could reasonably be full at the same time, the number to consider is the total for the premises, not each room in isolation. Trinity records 350 and is in scope.

Because it is a place of worship, Trinity is standard tier regardless — even at 350, and even if a carol service pushed it past 800.

What to write down

Keep it to a few lines, and keep it where the next person will find it — the same folder as your fire risk assessment is ideal.

• The figure.
• Which of the six methods you used.
• The date and the document it came from.
• Anything that would change it, such as a planned extension or a licence variation.

Review it when the building changes, not on a calendar.

If you are close to 200

Plan as though you are in scope.

The standard tier duties are four written procedures and making sure your people know them. There is no requirement to buy equipment, hire security staff, or commission a risk assessment. The cost of preparing when you did not strictly need to is a few hours of someone's time.

The cost of deciding you were out of scope and being wrong is a penalty of up to £10,000, and a building full of people who were never briefed.

If you would rather have the answer worked out for you, the scope checker asks seven plain-English questions and takes about two minutes.