Sustainable Event Planning: A Practical Framework for Lower-Emission Events

Sustainable event planning often starts with reusable lanyards and paper straws. Those choices are visible, but they rarely move the number sponsors, clients and RFPs now ask about: the event's carbon footprint. The choices that do move it are made months earlier, in the planning meeting.

Sustainable event planning means making the choices that cut the most emissions first — format, location and attendee travel — then addressing venue energy, hotels, food, materials and waste, and measuring the results. Travel accounts for about 70–90% of an average event's emissions, according to the Net Zero Carbon Events measurement methodology. So the biggest wins come from decisions about where people come from and how they get there.

This framework works in eight steps, in order of impact:

1. Decide the format.
2. Choose a location close to your audience.
3. Pick a low-impact venue.
4. Shift how people travel.
5. Plan accommodation.
6. Make the menu plant-forward.
7. Reduce materials and waste.
8. Measure, report and improve.

The framework at a glance

Step	Decision	Why it matters	When to decide
1. Format	In person, hybrid or online	Sets how many people travel at all	At concept stage
2. Location	Host city relative to your audience	Sets how far people travel and how many fly	Before venue search
3. Venue	Transit access, energy, hotel proximity	Affects local travel and energy	During venue selection
4. Travel	Rail, coaches, carpools, group fares	Shifts travel to lower-carbon modes	Before registration opens
5. Accommodation	Hotel location, number of nights	Scales with every traveler and night	During contracting
6. Food	Plant-forward default, right-sized orders	Food is the next largest controllable source	During catering contracting
7. Materials and waste	Reuse, digital, diversion	Visible, credible and often cheaper	Throughout planning
8. Measurement	Baseline, budget, final footprint	Proves progress and guides next time	Before, during and after

Step 1: Decide the format

Before choosing a city, ask whether everyone needs to be in the room. Cornell researchers found that moving a conference fully online cut its footprint by 94%. A hybrid with at least half of attendees in person cut it by about a third.

Hybrid works best when remote attendance replaces the longest trips. The industry's Net Zero Roadmap also cautions that simply moving events online "is not a long-term solution," since in-person connection has real value. Use hybrid to cut long-haul travel, not to replace every event.

Step 2: Choose a location close to your audience

Location is the decision that sets the ceiling on your footprint. Map where your attendees come from, then pick a city that most of them can reach by car, rail or a short flight. The Net Zero Roadmap urges organizers to "base destination or venue selection on criteria related to minimising attendee travel."

A "central" city on a map isn't central if most of your audience lives in one region. For more on why travel dominates, see our guide to what makes up an event carbon footprint.

Step 3: Pick a low-impact venue

Within your chosen city, look for:

• Transit access, so attendees can arrive by rail or walk from hotels.
• Renewable electricity or a clean local grid.
• Hotels within walking distance, to cut shuttles and taxis.
• A sustainability management system. Many venues follow ISO 20121, the international standard for event sustainability management, updated in 2024.

Step 4: Shift how people travel

Once the location is set, the next lever is how attendees get there. The difference between modes is large, even for the same trip.

Here's a comparison for 100 attendees traveling 400 miles round trip, using factors from the EPA GHG Emission Factors Hub. All inputs are illustrative.

Travel mode	Emissions (kg CO2e)
Driving alone (100 cars)	11,943
Short-haul flight	8,357
Carpooling, 3 per car (about 33 cars)	3,981
Intercity rail, U.S. national average	3,870
Bus	2,665
Rail, Northeast Corridor	922

Rail on a corridor like Boston to Washington produces about 90% less than flying the same distance. Ways to encourage the switch:

• Negotiate group rail fares and include them in registration confirmations.
• Run shuttles or coaches from major hubs.
• Offer a carpool board for attendees driving from the same region.
• Schedule sessions around train times, not just flight times.

Step 5: Plan accommodation

Hotel emissions scale with every traveler and every night. Keep them down by:

• Choosing hotels within walking distance of the venue.
• Avoiding unnecessary extra nights with schedules that let regional attendees arrive and leave the same day.
• Asking hotels for their footprint per room-night. Many can report it using the Hotel Carbon Measurement Initiative (HCMI).

Step 6: Make the menu plant-forward

Food is usually the next largest source an organizer controls directly. Projet Celsius, citing France's ADEME database, puts a beef-based meal at 6.29 kg CO2e and a vegetarian meal at 0.51 kg, about 12 times less.

• Make vegetarian the default, with meat available on request.
• Right-size orders using registration data and pre-booked meals.
• Donate or compost leftovers. The Net Zero Roadmap targets a 50% reduction in food waste by 2030.

Step 7: Reduce materials and waste

Materials and waste are usually a small share of total emissions, but they're highly visible and often save money.

• Reuse signage, badges and booth elements across events.
• Go digital for programs and agendas.
• Skip low-value swag, or choose useful, durable items.
• Plan for diversion. The Net Zero Roadmap aims for at least 50% of event waste to be diverted from landfill by 2030.

Step 8: Measure, report and improve

Measurement turns good intentions into proof. Estimate the footprint before the event, collect real data during it, and report the final number afterward.

• Set a baseline from last year's event or a planning estimate.
• Set an emissions budget and reduction target.
• Collect travel data at registration, and get hotel, venue and catering data from suppliers.
• Report total and per-attendee emissions, with your boundary and assumptions.
• Address residual emissions only after real reductions, and avoid offset-only "carbon neutral" claims.

Common mistakes in sustainable event planning

• Starting with small, visible fixes. Cups and lanyards can't offset a host city that requires most people to fly.
• Picking the venue before the city. The city choice sets most of the footprint.
• Assuming hybrid is always lower. It only helps when it replaces long trips.
• Not measuring. Without a baseline, you can't prove progress to sponsors or clients.
• Relying on offsets first. Reduce first, then address what remains.

How Aclymate supports sustainable event planning

Aclymate gives event and sustainability teams the data to plan lower-emission events and prove the results.

• Start with a free baseline. Aclymate Explorer estimates your company's Scope 1, 2 and 3 footprint, including travel.
• Track every event over time. Aclymate Navigator supports activity-based and spend-based calculations, with dashboards that show trends against your baseline.
• Let experts gather the data. Aclymate's Carbon Bookkeeping service organizes travel, hotel, venue and catering records.
• Hand off the whole job. With Aclymate One, Aclymate's team handles data collection, reduction planning and reporting alongside the software.
• Prove your progress. Aclymate's Climate Wise, Climate Leader and Net Zero certifications give sponsors and attendees credible proof.
• Address what remains. Aclymate offers science-backed offset portfolios and REC guidance for residual emissions.

Branded merchandise distributor Whitestone used Aclymate to measure a 4,053 tCO2e annual footprint and earn Climate Leader certification.

Frequently asked questions

What is sustainable event planning?

It's planning events to reduce their environmental impact, especially carbon emissions. It starts with the choices that cut the most carbon, such as format, location and attendee travel, then covers venue, hotels, food, materials, waste and measurement.

What is the most important part of sustainable event planning?

Location and travel. Travel accounts for about 70–90% of an average event's emissions, according to Net Zero Carbon Events, and the host city decides how far attendees travel and how many fly.

Are hybrid events more sustainable?

Usually, if remote attendance replaces long trips. A Cornell study found a hybrid format with at least half of attendees in person cut a conference's footprint by about a third, and a fully online format cut it by 94%.

How can I reduce travel emissions for an event?

Choose a location close to most attendees, encourage rail and coaches with group fares and shuttles, and offer carpooling. In our example, Northeast Corridor rail produced about 90% less than flying the same distance.

What certifications exist for sustainable events?

ISO 20121 is the international standard for event sustainability management. Organizers can also certify their company's climate progress, for example through Aclymate's Climate Wise, Climate Leader and Net Zero certifications.

How do I measure whether my event is sustainable?

Measure its carbon footprint before, during and after the event, and compare it with a baseline. Track waste diversion and food waste too. Report total and per-attendee results with your assumptions.

Plan your next event around what matters most

The most sustainable events aren't the ones with the most green touches. They're the ones where the big decisions about format, location and travel were made with carbon in mind.

Ready to plan lower-emission events? Start free with Aclymate Explorer to get a baseline in minutes, or book a demo to see how Aclymate's software and experts can measure, reduce and report your event and company emissions without adding headcount.