How to Report Business Travel Emissions for CSRD (Flights, Hotels, Trains)
Business travel is one of the most common — and most consistently underestimated — sources of Scope 3 emissions for small and growing businesses (SMEs). Whether your team travels by plane, train, or car, those journeys contribute to your company’s overall carbon footprint and must be accounted for under CSRD and VSME reporting.
The good news is that you do not need complex software or perfect data to comply. The European Sustainability Reporting Standards (ESRS E1) and VSME Standard (EFRAG 2024) both allow well-documented estimates when travel records are incomplete. This guide walks through what counts, how to calculate it, and how to disclose it clearly.
For general guidance on handling gaps in your sustainability data, see How to Estimate Missing Data for CSRD Reporting.
1. What Counts as Business Travel Under CSRD?
Business travel covers all transport and accommodation used by employees for work-related purposes, excluding daily commuting. It falls under Scope 3, Category 6 of the GHG Protocol.
Activities that must be included:
| Travel type | Examples | Notes |
|---|---|---|
| Flights | Domestic, regional, long-haul | Include radiative forcing (RFI) for flights |
| Train and rail | Inter-city, international rail | Typically low-carbon; still reportable |
| Company cars | Business journeys only | Commuting is excluded |
| Hire cars and taxis | Client visits, airport transfers | Include if paid or reimbursed by company |
| Hotel stays | Overnight accommodation for work | All locations, not just EU |
| Ferry and coach | Where relevant to your sector | Include if business-paid |
Travel paid or reimbursed by the company must be included regardless of destination. Personal leisure travel does not count.
2. What Data Do You Need?
Start by identifying where travel information already exists in your business:
- Travel agency invoices — usually include route, transport mode, and class
- Expense claims and credit card reports — cover individually booked travel
- Online booking platform exports — many tools (Booking.com for Business, TravelPerk, Concur) can export annual summaries
- Mileage logs — for personal car use reimbursed by the company
- Hotel booking confirmations — for nights stayed when not booked centrally
For each trip, ideally record:
- Travel mode (flight, train, car, hotel)
- Distance in km, or spend in € if distance is not known
- Class of travel (economy, business, first) — for flights, this affects the emission factor
- Number of nights (for hotels)
If your records are incomplete, estimate using spend or typical journey distances — this is explicitly allowed under CSRD and VSME proportionality rules.
3. Calculating Emissions by Transport Type
Flights
Flights are typically the largest source of business travel emissions. Use the following emission factors, which include a Radiative Forcing Index (RFI) of 1.9 to account for non-CO₂ warming effects at altitude:
| Flight type | Distance | Economy class (kg CO₂e/passenger km) | Business class multiplier |
|---|---|---|---|
| Short haul | Under 1,500 km | 0.254 | ×1.26 |
| Medium haul | 1,500–4,000 km | 0.195 | ×1.26 |
| Long haul | Over 4,000 km | 0.146 | ×2.40 |
Example: Two employees fly London to Frankfurt (1,150 km each way, short haul, economy).
- 2 passengers × 2,300 km round trip × 0.254 = 1.17 tCO₂e
Source: DEFRA 2024 emission factors. ADEME Base Carbone and EEA provide equivalent EU-aligned figures.
Train and Rail
Train travel is significantly lower-carbon than flying and is increasingly the default for shorter routes in many EU countries.
| Mode | Emission factor (kg CO₂e/km) |
|---|---|
| Electric inter-city train (EU average) | 0.012 |
| Diesel train | 0.045 |
| Metro or light rail | 0.030 |
| Long-distance coach | 0.027 |
Example: One employee travels Paris to Amsterdam by train (510 km each way).
- 1,020 km × 0.012 = 12.2 kg CO₂e — compared to roughly 200 kg CO₂e for the equivalent flight.
Cars and Taxis
For company cars or hire cars, use the fuel type where known. For reimbursed personal vehicle use, apply the blended average if fuel type is not recorded.
| Vehicle type | Emission factor (kg CO₂e/km) |
|---|---|
| Petrol car (medium) | 0.180 |
| Diesel car (medium) | 0.165 |
| Hybrid car | 0.110 |
| Electric car (EU grid average) | 0.050 |
| Blended average (unknown fuel) | 0.170 |
| Taxi (petrol, estimated) | 0.210 |
Example: An employee drives 8,000 km per year on company business in a petrol car.
- 8,000 × 0.180 = 1.44 tCO₂e
Hotels
Accommodation emissions are calculated per night stayed, using average emission factors by hotel type:
| Hotel category | Emission factor (kg CO₂e/night) |
|---|---|
| Budget or economy | 10–15 |
| Mid-range (3-star equivalent) | 20–30 |
| Upscale (4–5 star) | 40–60 |
| Eco-certified property | 5–12 |
If you do not know the hotel category, use 20 kg CO₂e per night as a conservative mid-range estimate.
Example: Your team stays a combined 80 hotel nights per year.
- 80 × 20 = 1.6 tCO₂e
Rather than calculate each mode by hand, you can use our calculator — it applies DEFRA 2024 factors across flights, rail, car, and hotel nights and produces a breakdown you can drop straight into your disclosure:
Calculate Your Business Travel Emissions
Flight Travel
Add your business flights (optional)
How many one-way flights did you take?
Approximate distance per flight
4. What to Do with Incomplete Data
Many SMEs do not have centralised travel records, particularly for individually expensed trips. Here is a practical approach for each gap:
| Data gap | Estimation method |
|---|---|
| No distance records for flights | Use great-circle route distances (available via online calculators) |
| No booking class recorded | Default to economy class for all flights |
| Expense claims only (no distances) | Apply spend-based factor: approximately €0.35 per kg CO₂e for air travel |
| Hotel type unknown | Use mid-range default (20 kg CO₂e/night) |
| Partial year data | Annualise from the months available; note the assumption |
Document all assumptions clearly. CSRD expects transparency about methodology — a clear note is better than silence about how you estimated.
For more on handling data gaps across all reporting topics, see How to Estimate Missing Data for CSRD Reporting.
5. How to Disclose Travel Emissions in Your Report
Under ESRS E1-6 (climate mitigation) and VSME B7 (energy and GHG data), your disclosure should cover:
- Total business travel emissions by transport type (flights, rail, car, hotel)
- Estimation methods used — distance-based, spend-based, or default factors
- Emission factor sources referenced (DEFRA, ADEME, EEA, IPCC)
- Actions taken or planned to reduce travel or shift to lower-carbon options
Example disclosure:
“In 2025, total business travel emissions were estimated at 28.5 tCO₂e, comprising 65% from flights, 25% from hotel stays, and 10% from car and rail travel. Distance-based calculations used DEFRA 2024 emission factors, with a radiative forcing index of 1.9 applied to all flights. Hotel emissions were estimated using a mid-range default of 20 kg CO₂e per night. The company promotes train travel for journeys under 600 km and virtual meetings where client relationships allow.”
This level of disclosure meets CSRD expectations for transparency and traceability, and it demonstrates that your data is methodologically sound even if it relies on estimates.
6. Reducing Business Travel Emissions
Reducing travel is often one of the fastest and most visible improvements an SME can make to its Scope 3 footprint. Practical actions:
- Establish a “train under 600 km” policy — covers most intra-European business travel routes
- Default to video conferencing for internal meetings and early-stage client calls
- Book eco-certified hotels — many major chains now offer certified properties at no premium
- Use corporate booking platforms with sustainability filters (TravelPerk, Spotnana) to automate data capture and reduce emissions at the point of booking
- Track air travel class — shifting one long-haul trip from business to economy class can reduce per-passenger emissions by 60%
- Set annual targets — committing to a percentage reduction creates accountability and gives you a progress story to tell in your report
These actions can be reported under both ESRS E1 (climate mitigation) and VSME B7, and they demonstrate continuous improvement rather than just compliance.
Frequently Asked Questions
Do I need to include travel booked and paid for personally by employees?
Yes, if the travel is reimbursed by your company. All company-reimbursed transport and accommodation counts as business travel under Scope 3 Category 6. Personal travel that is not reimbursed does not count.
What if I only have travel spend, not distance data?
You can use spend-based emission factors. For air travel, a rough approximation is 1 kg CO₂e per €0.35 spent on flights (economy class, EU average routes). Disclose clearly that you used a spend-based approach and reference your factor source. Over time, improve to distance-based calculations as you collect better data.
Should I include hotel stays outside the EU?
Yes. All business travel — domestic and international — forms part of your Scope 3 inventory. There is no geographic restriction on what must be included.
Do I have to separate flights by class of travel?
If you have the data, yes. Business-class long-haul travel carries emissions roughly 2.4 times higher than economy class due to the greater cabin space per passenger. If booking class is not recorded, default to economy and note this assumption.
How do I handle travel by a mix of transport modes on one trip?
Calculate each leg separately and sum them. For example, a trip involving a train from Amsterdam to Brussels, then a flight from Brussels to Madrid, would be calculated as: train leg (Eurostar or Thalys equivalent) + flight leg (medium haul, economy).
Key Terms
- Scope 3 Category 6 — Business travel emissions: indirect emissions from transport and accommodation used by employees for work purposes.
- Radiative Forcing Index (RFI) — A multiplier applied to flight emission factors to account for non-CO₂ warming effects of aviation at altitude. Standard value: 1.9.
- Emission factor — The average CO₂e released per unit of activity (e.g. per passenger km, per night).
- VSME B7 — The VSME Standard data point covering energy use and greenhouse gas emissions, including business travel.
- ESRS E1-6 — The ESRS disclosure requirement covering climate-change mitigation actions, including reductions in travel emissions.
- Distance-based calculation — Preferred method: total distance (km) × emission factor per km.
- Spend-based calculation — Fallback method: total spend (€) × emission factor per €, used when distance data is unavailable.
Conclusion
Reporting business travel emissions is straightforward once you identify your data sources and choose the right calculation method. Start with what you have — invoices, expense reports, booking confirmations — estimate gaps using documented assumptions, and disclose your methodology clearly.
Over time, investing in centralised travel booking and better record-keeping reduces estimation uncertainty and strengthens your data for assurance purposes. Even in Year 1, a well-documented estimate is fully compliant with CSRD and VSME expectations.
