Reporting event emissions for CSR and annual reports: a template for b2b marketers

Nobody asks for the carbon data while the keynote is running smoothly.

They ask later, when the event is finished, the CSR report is being drafted, and someone needs a number that can stand up in front of finance, procurement and the board.

That is usually when the problem appears. The venue has part of the energy data. The registration platform has the travel clues. The AV supplier has freight details. Catering has meal counts. Waste figures may sit in a post-event report nobody has opened yet.

The information exists, but not in one place.

That is why event emissions reporting has to start before the lanyards are printed and the first truck arrives on site. With a clear boundary, named data owners and a simple reporting template, B2B marketers can turn a busy live event into a carbon figure that is not perfect but is clear, traceable and defensible.

What counts as event emissions?

Event emissions are the greenhouse gas emissions created by planning, producing, hosting and closing an event.

They can include venue energy, on-site fuel, attendee travel, speaker and crew travel, freight, catering, accommodation, signage, temporary build, digital activity and waste.

For most corporate events, the largest and hardest section is Scope 3 event emissions.

The GHG Protocol Corporate Standard separates emissions into three scopes:

Here is the detail that many teams miss.

If you rent a hotel ballroom, exhibition hall, conference venue or event space, do not automatically treat the venue’s electricity as Scope 2. In many cases, it sits in Scope 3 because the venue buys the energy, and your event uses part of that service.

If your organisation owns the venue or buys the electricity directly, it may sit in Scope 2.

That boundary decision matters. It affects how event data is rolled into wider company reporting. It also helps prevent double-counting later.

A simple rule helps:

If your organisation owns or directly controls the source, look at Scope 1 or Scope 2. If another party provides the service, supplier, venue, transport or material, it is usually Scope 3.

Which reporting frameworks apply to UK event emissions?

UK event emissions reporting usually draws from five main sources:

• GHG Protocol Corporate Standard
• UK Government SECR guidance
• ISO 14064-1
• ISO 20121
• Net Zero Carbon Events

Each serves a different job.

SECR is not an event-only framework. It is a wider UK corporate reporting requirement. For organisations already reporting energy and carbon information, event activity may feed into that broader disclosure.

ISO 14064-1 supports greenhouse gas quantification and reporting at the organisation level. ISO 20121 is about how events are planned and managed in a more sustainable way.

In simple terms, ISO 20121 helps shape how the event runs. ISO 14064-1 helps support how emissions are reported.

Net Zero Carbon Events gives the events sector a shared direction, including long-term reduction planning and net zero alignment.

A practical approach is this:

Use the GHG Protocol to structure the scopes. To calculate emissions from activity data, use UK Government conversion factors. Use ISO 20121 to improve event planning and supplier choices. And use ISO 14064-1 principles when the inventory needs a stronger audit trail.

Where could CSRD and ESRS come into view?

If your organisation has EU operations, EU-facing reporting obligations, or group-level sustainability disclosure requirements, event emissions data may also support wider CSRD and ESRS reporting.

That does not mean CSRD is an event-only framework. It is much broader than that. But event data can still feed into climate, energy, value chain and Scope 3 disclosures where the organisation falls within scope.

This is also where double materiality, which means looking both ways, becomes useful. 

• How sustainability issues affect the business.
• How the business affects people and the environment in return.

For events, that usually means looking at travel, freight, catering, venue energy, materials and waste, alongside any financial, operational or reputational risk linked to poor reporting.

The key point is simple: if event data may end up in a wider annual reporting process, collect it with enough structure that it can be reused later.

Some corporate sustainability reporting processes also require structured digital reporting formats. That is another reason to keep event data clean, consistent and traceable from the start.

The event emissions reporting template

A good event carbon reporting template should record more than a final number.

It should show:

• The reporting category.
• The data owner.
• The raw activity data.
• The evidence source.
• The conversion factor used.
• The tCO₂e result.
• The confidence level or reporting note.

That is what turns a spreadsheet into something useful for CSR, finance, procurement and board-level reporting.

To make this easier, we have created a practical event emissions reporting template. Use it once you have agreed on the reporting boundary and before supplier data starts getting lost in inboxes, invoices and post-event folders.

The template gives your team a working place to record the event profile, Scope 1, Scope 2 and Scope 3 activity, evidence sources, confidence notes, gross emissions, net emissions, assumptions, exclusions and sign-off.

Here is a short preview of what the reporting areas should cover:

The most important part is not the table itself. It is the reporting discipline it creates.

Every line needs a source, an estimate needs a note, and every assumption needs to be visible.

That is what makes the number defensible.

Start with a clear boundary statement

Every event report should include a short boundary statement.

Use this as a starting point:

That final sentence matters.

Every event footprint includes assumptions. Strong reporting does not hide them. It names them.

Without a boundary statement, the final carbon number can look cleaner than it really is. That creates problems later when finance asks why last year’s number was lower, or when a board member asks whether attendee travel was included.

A boundary statement makes the method visible.

A simple worked example

Let’s say you run a leadership conference for 450 attendees.

You receive travel survey responses from 140 attendees. The survey asks for the starting location, main travel mode and whether the journey was a return.

You scale the sample to the full attendance figure, then apply the relevant UK Government conversion factors for the event year. 

Your reporting note might read like this:

That note is more useful than a neat number with no explanation behind it.

A CSR lead does not just need the total. They need to know where it came from.

How to collect event emissions data without a sustainability team?

Data collection works best when it is built into the production timeline.

Ask for emissions evidence before contracts are signed, not after the debrief.

The aim is not perfect science. The aim is a clear method, named data owners and enough evidence for the result to stand up to internal review.

Start with venue energy

Ask the venue for metered kWh for the event space, including build and break days where relevant.

This may include electricity, heating, cooling, event power, catering power and shared-area use, depending on what the venue can provide.

If the venue cannot separate your event from a shared meter, agree an apportionment method. Common options include floor area, event hours, occupied space or the venue’s own calculation method.

Record the method clearly.

Do not just write “estimated”. Say how the estimate was made.

Add travel questions early

Travel is often the biggest missing piece because teams leave it too late.

Add three short questions to registration or post-event feedback:

• Where did you travel from?
• What was your main travel mode?
• Was this a return journey?

Keep it short. Long surveys rarely get completed.

If you only receive partial responses, record the sample size and scaling method. A transparent estimate is better than a silent omission.

Include speakers, crew and suppliers

Many event reports include attendees but forget the people who make the event happen.

That can leave gaps.

Include:

• keynote speakers
• panellists
• production crew
• AV technicians
• interpreters
• event staff
• supplier teams
• stand builders
• couriers and logistics providers

These journeys may be shorter than attendee travel. They are still part of the event footprint. Their travel still belongs in the footprint if it was needed to deliver the event. 

Ask suppliers before the job closes

Freight, AV, set-building, printing and exhibition suppliers often hold the most useful data. 

Ask for:

• Vehicle type
• Delivery mileage
• Number of loads
• Material weights
• Reuse or disposal route
• Whether waste transfer notes are available

That conversation is much easier before the project has been closed and filed away. If you wait until the annual report deadline, the person with the answer may have moved on. They may already be handling the next event, supplier request, or invoice folder.

Use the correct conversion factors

Use the UK Government conversion factors for the year the event took place, not the year you are writing the report.

That sounds small, but it is one of the most common reporting mistakes.

For example, if the event happened in 2026, use the 2026 conversion factors.

If the event happened in 2025, use the 2025 factors.

Changing conversion factor years without noting it can make year-on-year comparisons harder to defend. 

Keep a clear audit trail

Treat the evidence trail with the same discipline as finance records.

For each reporting line, record:

• Who supplied the number?
• When it was received
• What the raw activity data was.
• Which conversion factor was used
• Where the evidence is stored.
• Confidence level for the figure 

For one event, a spreadsheet may be enough. For repeated annual reporting, store the data somewhere shared, version-safe and easy for finance, sustainability, procurement and event teams to access together.

How to present event emissions in a CSR or annual report?

Event emissions usually sit inside the environment, ESG, sustainability or operational carbon section of the report.

Present:

• Gross emissions.
• Net emissions if offsets are used.
• The scope split.
• The event boundary.
• The method.
• Exclusions.
• Year-on-year comparison where relevant.

For the executive summary, use one plain line:

Our 2026 leadership conference generated [X] tCO₂e gross emissions. Attendee travel, venue energy, and freight were the largest measured sources.

In the main reporting section, use a compact comparison table like this:

If your reporting boundary has changed, say so clearly.

For example:

That one sentence can save a difficult board question later.

Gross vs net emissions

Keep gross and net figures separate.

Gross emissions show the footprint before offsetting.
Net emissions show the figure after verified offsets, if offsets are used.

Do not use offsets to blur the original footprint. A clear format looks like this:

If offsets are included, state the provider, project type, volume retired and registry evidence.

How do event production choices affect the final number?

The best event emissions reporting does not begin after the event. It begins during planning.

A few decisions can change the final footprint before anything is built:

• Choosing a venue close to public transport.
• Reducing freight journeys.
• Reusing staging, screens and scenic structures.
• Designing signage for reuse.
• Choosing lower-impact catering options.
• Using hybrid formats only where they reduce unnecessary travel.
• Asking suppliers for data before contracts are signed.

Renting infrastructure instead of buying new materials can also reduce avoidable carbon impacts. Reusing screens, staging structures, lighting and AV systems spreads the manufacturing footprint across multiple events.

That is where joined-up event production matters.

Production, logistics and reporting should support each other rather than sit in separate silos.

EMS Events supports corporate conferences, summits, exhibitions, and hybrid or virtual events. We also deliver technical event production across London and the UK. Because emissions data for events is often held by venues, AV teams, stand builders, caterers and logistics suppliers, it helps to bring production and reporting discussions together early. This gives clients clearer evidence before the event ends.

For example, an event production team can identify suppliers that hold material weights. They can spot deliveries that can be combined and check if the stage set design and build assets can be reused. They can also assess whether hybrid production cuts travel or simply adds another emissions category.

The same applies to event printing and branding. If signage, graphics and printed assets are planned for reuse, storage or responsible disposal from the start, the reporting trail becomes cleaner, and the final event footprint becomes easier to explain. 

The earlier these decisions are made, the easier the final report becomes.

Common reporting mistakes B2B marketers make

Most reporting mistakes come from rushed collection, unclear ownership or weak boundaries.

Avoid these:

• Reporting only venue energy while ignoring travel.
• Classifying all venue electricity as Scope 2 without checking who bought the energy. 
• Confusing energy consumption with emissions by forgetting the conversion step.
• Asking suppliers for data after they have closed the job.
• Excluding speaker, crew and freight travel because they are not delegates.
• Using outdated conversion factors.
• Reporting a single tCO₂e figure with no named method behind it.
• Using offsets to hide the gross emissions figure.
• Comparing years when the reporting boundary has changed.
• Treating a one-off estimate as if it were a precise, audited figure.

A good event emissions report does not need to pretend it is perfect. It needs to be clear, consistent and traceable.

Final thought

Event emissions reporting is not about producing a perfect carbon number once the event is over. 

It is about agreeing on what counts, collecting evidence while the event is live and presenting a clear figure that your CSR, finance and leadership teams can actually use.

The simplest way to start is to use one consistent working method for every event. Record the boundary. Name the data owners. Keep the evidence. Separate gross and net emissions. State the assumptions.

For support with event production, supplier coordination, hybrid delivery, AV logistics and sustainability data capture, speak to the EMS Events team before your next event brief is finalised.

FAQs

What emissions should be included in an event carbon report?

An event carbon report should include venue energy, on-site fuel, attendee travel, speaker and crew travel, supplier freight, catering, accommodation, materials, signage, digital infrastructure and waste. Classify an activity as Scope 1 or Scope 2 only where your organisation controls the source or buys the energy directly. Most rented event activity sits in Scope 3.

Where do event emissions sit in a CSR report?

Event emissions usually sit in the environment, ESG, sustainability or operational carbon section of a CSR report. For larger organisations, the figures may also feed into wider Scope 3 reporting. Include the event boundary, gross emissions, net emissions, exclusions, method and year-on-year comparison.

Is event emissions reporting mandatory in the UK?

Event emissions reporting is not usually mandatory as a standalone event report. However, large organisations may need to report broader energy and carbon data, and event activity can feed into those wider disclosures. Always confirm your organisation’s reporting position with the finance or sustainability lead.

How do you calculate emissions from attendee travel?

Collect origin, destination, travel mode, distance and return journey data through registration fields, postcode data or a short post-event survey. Then apply recognised conversion factors. Where data is incomplete, state the sample size, scaling method and assumptions used.

What is the difference between ISO 20121 and ISO 14064 for events?

ISO 20121 helps teams manage events more sustainably through planning, supplier choices and operational controls. ISO 14064-1 supports greenhouse gas quantification and reporting at organisation level. In simple terms, ISO 20121 shapes how the event is managed, while ISO 14064-1 supports how emissions are reported.