Anyone who has organised a corporate event for 300 people knows the feeling: three months before the date, you realise the venue search takes far longer, the catering effort has exploded and the trainer ratio doesn't add up. This checklist shows what needs to be done and when — sorted by the months remaining until the event.
6 months out: Lock in format and venue
The most important lesson from 25 years of large-group events: the venue search is the bottleneck. Spaces for 200+ in the DACH region are often booked 12 months in advance, especially in the May–September peak season. Starting at 6 months gives you a real shot at good options — at 3 months it gets tight.
- Roughly pin the event format: indoor, outdoor, or hybrid?
- Request and pre-reserve 3–5 venue options (even if not yet final)
- Clarify the budget frame: typical large-group events run €60–90 per person including logistics buffer
- Engage stakeholders inside the company — who decides, who sponsors, who runs internal comms?
4 months out: Trainer team and insurance
Now the detail planning kicks in. For large groups from 200 you need 4–6 trainers plus reserve — not casual helpers but experienced event pros who have already run several large-group programs.
- Lock in the event agency and sign the contract
- Agree on trainer team size: rule of thumb 1 trainer per 30–50 participants depending on format
- Clarify insurance: event liability extension typically costs €100–500 and is mandatory
- For outdoor events: apply for noise permits (lead time 4–12 weeks)
- Reserve a backup venue for plan B — ideally at the same site
2 months out: Catering, material, communication
Logistics gets concrete. This is where most hidden costs appear — items missing from initial estimates but significant at scale.
- Catering rule of thumb: one buffet line per 80 people — at 300 participants that's at least 4 parallel service stations, otherwise 25-minute queues form
- Mobile toilets for outdoor: 1 unit per 50 participants
- Check shuttle service if the venue is not central — a 50-seater coach costs €600–900 per day
- Send invitations including directions and dress-code hints
- Clarify material logistics: 30 tablets, 500 banners — that doesn't fit in the trainer's car, you need freight
2 weeks out: Detailed run-of-show and pre-event briefing
Now the plan that carries every transition on the event day takes shape. For large groups every switch must be timed — and it must be clear who does what when.
- Minute-by-minute run-of-show: when does what start, who moderates, where is catering
- Apply the buffer rule: +50 % on every transition above 100 people, +100 % above 300
- Pre-event briefing with the trainer team and the client (30–60 minutes, phone or video)
- Finalise participant list including special needs (allergies, mobility, language)
- Weather cut for outdoor: who decides by when whether to move? 24 hours before event is a proven mark
48 hours out: Last-minute check
The decisive reality check. Anything corrected here is saved from the event-day chaos.
- Venue check: power outlets, microphone test, emergency exits, assembly area
- Verify material delivery the day before — nothing is worse than missing tablets in the morning
- Final trainer team briefing, reserve trainer on standby
- Weather forecast: activate plan B or not?
- Communication to participants: meeting point, arrival, clothing — last reminder email
Event day: What the pros do differently
At anydoors we have routines from 25 years of large-group experience that smaller agencies often haven't established — and which matter exactly when 300 people need to move somewhere at once:
- Trainer reserve always present. At every large-group event there is at least one more trainer on standby than planned — illnesses and spontaneous adjustments always happen
- Central comms hub. For outdoor events with distributed stations, live communication must run, otherwise dead zones appear
- Catering escalation ready. When the buffet runs dry, replenishment must be there in 10 minutes — not "we'll see"
- Clear handover choreography. Moving 300 people from station A to station B is a small science — only works with clear moderation and visualisation
Read the full practitioner guide
This article shows the timeline. If you want to go deeper on trainer ratios, hidden costs, indoor-vs-outdoor, schema, and real examples, you'll find the full breakdown in the main guide: Team Events for Large Groups — Moving 100, 200 or 500 People.
Or contact us directly. For large-group projects we deliver a concrete concept within 24 hours: format recommendation, logistics plan and transparent quote. Get a quote →