If you’ve ever run a corporate event or trade show, you’ll know the logistics are complicated enough before you start thinking about emissions. But for sustainability managers and event planners reporting on Scope 3, the question isn’t whether your event has a carbon footprint. It’s where that footprint actually sits and what you can realistically do about it.
The answer isn’t always obvious, and some of the biggest reduction opportunities are in categories most organisers overlook. Here’s a breakdown of what the data says across each major emission source.
Delegate Travel: The Biggest Number You Can’t Fully Control
Delegate travel is, by a wide margin, the single largest contributor to an event’s total emissions. Data from isla, the UK events industry sustainability body, shows that attendee travel accounts for around 88% of total event emissions. That figure alone can make everything else look like a rounding error.
But here’s the catch: you don’t choose where your delegates live, and you can’t force them onto a train. You can encourage rail travel over short-haul flights, choose a venue with strong public transport links, and offer hybrid attendance options. Each of those will chip away at the number.
The UK government’s greenhouse gas conversion factors, published annually by the Department for Energy Security and Net Zero, provide the official emission factors for calculating travel-related carbon. Rail travel produces roughly 0.035 kgCO2e per passenger-kilometre, compared to around 0.126 kgCO2e for a short-haul flight. That’s more than a threefold difference.
Materials and Build: Where Organisers Have the Most Control
Once you strip out audience travel, the picture changes. isla’s A Closer Look: Materials report, drawing on over 6,400 material entries across 789 events logged in TRACE during 2025, found that materials account for 27% of an event’s carbon footprint when delegate travel is excluded. Remove staff travel too, and materials rise to 31%, making them the single largest controllable category for organisers.
Carpet is the worst offender. It carries the highest emissions of any build material, and around 78% of it is used once before going into a skip. Single-use banners, signage, and temporary structures all add to the problem. isla’s data shows that 84% of all event materials measured are virgin, meaning newly produced instead of reused, hired, or recycled.
Choosing reusable, UK-manufactured event infrastructure from tried-and-tests UK suppliers, like Gala Tent, will reduce both embedded transport emissions and the waste generated at teardown. A marquee or gazebo that’s built to last multiple events will carry a fraction of the per-use footprint compared to something that gets binned after one show.
Venue Energy, Catering, and Printed Materials
Venue energy is another contributor, though it varies hugely depending on the building. A purpose-built conference centre with an efficient HVAC system will produce far fewer emissions per delegate than a temporary outdoor setup running diesel generators. If you’re choosing between venues, ask for their energy data and check whether they’re sourcing renewable electricity.
Catering and food waste sit in a similar bracket. WRAP estimates that the UK hospitality and food service sector generates over a million tonnes of food waste each year, and events are a meaningful part of that total. Over-catering is the main culprit. Switching to pre-ordered meals, reducing buffet sizes, and donating surplus food through redistribution charities will all bring the number down.
Printed materials, including brochures, lanyards, and programmes, are often a smaller slice of the total. But they’re also one of the easiest to cut. Digital alternatives exist for almost every printed item at a conference, and the ones that don’t can usually be printed on recycled stock.
Where to Spend for the Biggest Return
Not every intervention costs the same, and not every one delivers the same return. For most organisers, the highest-impact changes per pound spent will fall into three areas: reducing single-use build materials, switching to reusable infrastructure, and improving venue energy efficiency.
Travel incentives like subsidised rail tickets or discounted hybrid passes can help too, but they require delegate buy-in and are harder to guarantee results from. Material choices, on the other hand, sit entirely within the organiser’s control and show up directly in the next year’s report.
A Footprint You Can Actually Shrink
Reporting on event emissions is increasingly expected under Scope 3 disclosure frameworks, and the data to back it up is getting better every year. The key takeaway for planners is that while travel dominates the headline number, the categories you can directly influence, especially materials and build, offer the clearest path to measurable, year-on-year improvement. Start with what you control, track it properly, and the reductions will follow.
