How to reduce business travel emissions

For travel managers, reducing emissions and reducing cost are largely the same problem. The choices that generate the most emissions also tend to cost the most: last-minute long-haul bookings, premium cabin upgrades, unnecessary short-haul flights, and airport taxis.

The most effective way to reduce business travel emissions is to ask three questions in order: 1) can the trip be avoided? 2) can it move to a lower-carbon mode? 3) Can the trips that remain be made more efficient?

This guide covers each lever, which ones to prioritise, how to get travellers to act on them, and how to measure the results.

1. Start with your baseline

You can't reduce what you can't see.

Before choosing any lever, build a baseline of your business travel emissions (Scope 3 Category 6). It should show where they come from: which modes, routes, teams, and travellers.

Three questions shape every reduction plan:

• Which modes dominate? For most enterprises, it's aviation.
• Where is the spend concentrated? A handful of routes, offices, or client sites often account for a large share of trips.
• Who travels most? Emissions are rarely spread evenly across a workforce. A small group of frequent travellers usually generates most of them.

Your baseline doesn't need to be perfect to be useful. A spend-based or distance-based first pass is enough to see the shape of your programme, and you can improve data quality as you go. Our business travel emissions guide explains how to calculate it.

2. Can the trip be avoided?

The lowest-carbon trip is the one that doesn't need to happen. That doesn't mean a travel freeze, just making sure each trip earns its place.

• Ask whether the trip is needed. For internal meetings, status updates, and early-stage conversations, a video call often does the job. Keep in-person travel for the moments where it adds most: new relationships, complex negotiations, workshops, and team time.
• Combine trips. Many programmes have travellers making several short trips to the same office or client within a few weeks. One slightly longer trip would often achieve the same outcome. Spotting these patterns needs cross-trip data that most booking tools don't show travellers, so the planning stage is the moment to step in. Our guide to reducing corporate travel spend covers trip consolidation in more detail.
• Make trips visible to teams. When teams can see their own travel emissions, they start to question trips themselves. Carbon budgets, covered below, are one way to do this.

3. Can it move to a lower-carbon mode?

For the trips that do need to happen, the biggest single reduction usually comes from changing how people get there.

Flight to rail

Not every route will have a viable rail alternative, but for journeys that do, rail is typically 70 to 90% lower carbon than an equivalent short-haul flight. It's often comparable in door-to-door time too, once you count airport queues and transfers. Most corporate travel policies already mandate rail for journeys under four hours, yet short-haul flights are still the default on many of these routes.

The gap is behaviour, not policy. A global consultancy with a rail mandate on the Amsterdam to London route still saw travellers booking out-of-policy flights. A personalised nudge sent after booking led 14% of them to cancel their flight, and rebook a Eurostar with 91% lower emissions (case study). See our rail emissions guide for how rail compares route by route.

Airport taxis to public transport

Airport transfers are among the most overlooked sources of business travel emissions, and one of the easiest to reduce. Switching from a taxi to public transport cuts emissions by over 70% for that journey.

To change traveller behaviour, you need to understand the airport taxi is a habit rather than a decision. A global engineering consultancy sent travellers a personalised route as they landed. It saw a 46% reduction in taxi journeys compared with travellers who got no nudge, saving £50 on each journey switched (case study).

Rental cars to rail or coach

For intercity trips under 500km, rail is typically cheaper than a rental car and 70 to 90% lower carbon. For group travel and events, coach is one of the lowest-carbon options per passenger. Where driving is unavoidable, an EV rental policy helps most in markets with clean electricity grids. See our rental car guide.

4. Can the trip be made more efficient?

When a flight is the right choice, there are still changes to be made to its footprint, and on a trip, hotels can be a major point of difference.

Cabin class

Premium cabins take up more space per passenger, so a business class seat carries 1.5 to 4 times the emissions of economy on the same flight. A clear cabin class threshold is one of the highest-leverage levers for programmes with a lot of long-haul travel. For example, you might allow business class only on flights over six hours or overnight routes. Our air travel emissions guide explains how cabin class is calculated.

Direct flights, booked early

Direct flights tend to be lower-emitting, because take-off and landing burn a disproportionate share of fuel. Booking early makes direct flights more likely to be available at a within-policy price. Flights booked two to four weeks in advance are around 21% cheaper per km than those booked within two weeks.

There's a big group to target here: 40% of business travellers book flights within seven days of travelling (Booking Window Optimisation). See also our guide to setting a corporate advance booking policy.

Carrier and aircraft choice

Not every flight on the same route carries the same emissions. Aircraft type, fleet age, and seat density all affect the emissions per passenger. Between London Heathrow and New York JFK, switching carrier can save up to 20% of emissions.

Nudging travellers towards lower-emission options on your busiest routes cuts aviation emissions without cutting trips. Thankfully, many booking tools now show an emissions estimate for each flight.

Hotels

Hotel stays can make up 10 to 20% of a programme's business travel emissions. The same night can carry very different emissions depending on where you stay. Indicative averages range from around 10.4 kg CO₂e per room night in the UK to around 76.6 kg in the Middle East (DEFRA 2025).

The choice of property within a city matters too. If your hotel spend is concentrated in a few preferred chains, ask them for property-level emissions data under the Hotel Carbon Measurement Initiative (HCMI). You can then steer travellers towards lower-emission properties. Our hotel emissions guide covers the methods, and the Thrust Carbon Hotel Sustainability Index scores every hotel in the world.

How programme-level levers can be used to reduce travel emissions

Travel policy design

Policies work best when they set specific thresholds rather than broad sustainability commitments. For example:

• rail for journeys under four hours;
• economy as the default for flights under four hours, with business class only above a set duration;
• a minimum booking window, such as two weeks;
• public transport as the default for airport transfers where it's practical.

Travel policies only work if travellers follow them, yet 46% of travellers never check the policy before booking. Our guide to travel policy compliance covers why policies go unenforced and how to fix it.

Implement carbon budgets

Setting carbon budgets by team or department creates accountability where travel decisions are made. Budgets work best when they're based on historical data and linked to your reduction target, so they're realistic but still ambitious. Teams should also be able to see their progress against them during the year.

Bring sustainability into supplier and carrier negotiation

If your travel is concentrated on a few routes, you have leverage to negotiate on sustainability as well as price. The same applies to preferred hotel chains, where you can ask for property-level emissions data.

Purchase sustainable aviation fuel (SAF)

SAF can cut the lifecycle emissions of flying, and some corporate programmes now buy it through their airline or TMC. It costs more than conventional jet fuel and supply is limited, so it works best alongside flying less and flying smarter. Before you count SAF purchases against your reported emissions, check how your reporting framework treats them.

To see where SAF fits in your wider plan, model it alongside your other levers. Thrust Carbon's NetZero Forecaster builds decarbonisation scenarios from your live emissions data, using levers such as SAF, cabin class, travel volume, aircraft efficiency, and policy implementation year. Each scenario comes with a future cost breakdown, so you can show stakeholders how much acting early saves.

What about offsets?

Carbon offsets don't reduce your reported business travel emissions. Under the GHG Protocol, your Scope 3 inventory reports the emissions your travel produced, and any offsets or removals you buy are reported separately. Offsets can be part of a wider climate strategy, but they aren't a reduction lever and shouldn't replace the steps in this guide.

Prioritising the reduction levers

This guide has gone through a lot of different options, and it can feel overwhelming knowing where to start.

Begin with the levers that cut emissions and cost together, need no new suppliers, and show results quickly. That usually means airport transfers, air-to-rail on your busiest short-haul routes, and earlier booking. Then move on to the structural levers that take longer to set up.

Ratings are a general guide, and your own baseline will show which levers matter most. A mostly short-haul European programme will get more from rail. A long-haul programme will get more from cabin class and carrier choice.

Influencing travel behaviour

Most of these reduction levers depend on a traveller making a more sustainable choice when they book or arrive. Policy reminder and annual sustainability emails rarely change behaviour. But by using a little bit of behavioural science, you can deliver real change in decision making.

Focus on the right travellers

You don't need to change everyone's behaviour. Around 30% of travellers generate around 70% of business travel emissions. Targeted interventions on that group move the needle, where blanket rules for the whole workforce often won't.

Intervene at the moment of decision

The most effective prompts arrive while the traveller is making the choice. That might be after they book a flight on a rail-eligible route, before a trip they usually book late, or as they land at the airport. Messages work best when they:

• name the traveller's actual trip, not the policy in general;
• lead with the benefit to the traveller, such as time saved, comfort, or a faster route;
• make the switch easy, with a direct link to change the booking or route and guidance on expensing it.

Make it personal and visible

Regular, personal summaries keep emissions in view between trips. One global engineering firm sends quarterly emissions summaries to more than 10,000 travelling employees. Each one compares the traveller with their team and business unit, with suggestions tailored to their travel, such as rail on a route they fly often. The emails get 2.5 times the industry-standard open rate (case study).

EngageAI delivers nudges that change behaviour at key decision moments

Thrust Carbon's EngageAI identifies the travellers who drive most of your emissions, predicts their upcoming trips, and sends personalised nudges by email, WhatsApp, Microsoft Teams, or Slack. It covers air-to-rail, earlier booking, and airport transfers. Because the same choices cut cost as well as carbon, it delivers a return on both. See how EngageAI works or estimate your savings.