What Martyn's Law obligations do offices have?

Most general offices don't trigger Martyn's Law because they aren't "publicly accessible" in the sense the Act defines. The Terrorism (Protection of Premises) Act 2025 targets premises where members of the public attend at scale, retail, hospitality, transport, education, healthcare, places of worship, sports and entertainment venues, and similar. A staff-only office with a controlled door policy generally isn't in scope. The catch is that most large offices have at least one publicly-accessible element, and that element can pull part of the building into scope on its own capacity numbers.

The publicly-accessible elements that typically matter in an office are: a reception or visitor lobby where members of the public arrive without prior vetting, customer-facing meeting rooms used by guests, ground-floor cafe or restaurant space open to passers-by, and event or town hall spaces hosting client-facing events. Capacity is calculated on the public-area portion only, including staff and visitors during those moments, not the full building roll.

A practical decision tree for an FM or head of workplace:

1. Does the office have any publicly accessible area? If pure staff-only with controlled access, exempt.
2. If yes, what's the reasonably-expected capacity of that public area? Below 200, exempt. 200 to 799, standard tier. 800 or more, enhanced tier.
3. For multi-tenant or serviced-office buildings, the coordination duty applies. The landlord or building operator typically leads compliance and tenants align with their procedures.
4. Get a formal Martyn's Law assessment to confirm tier and document the calculation.

Worked examples: a 50-staff SME with no public visitors is exempt. A 250-staff office with an open visitor reception and combined public-area capacity around 280 sits in standard tier. A 1,000-aggregate serviced building has a coordination duty led by the landlord. A corporate HQ with a 1,500-capacity town hall used for client events is in enhanced tier on the town hall portion, even where the working floors above remain out of scope.

What an in-scope office typically needs once tier is confirmed: public protection procedures (evacuation, invacuation, lockdown, communication), ACT eLearning for reception and front-of-house staff, and integrated emergency communications across PA, digital signage and mass notification.

Quick reference: staff-only offices exempt; publicly-accessible elements (reception, ground-floor cafe, client event space) trigger scope on the public-area capacity only; standard tier 200-799, enhanced tier 800+; multi-tenant buildings carry a landlord-led coordination duty.