Business travel is Scope 3, Category 6. It covers flights, accommodation, hire cars, taxis and rail for work.

Employee commuting is separate. See Run an employee commuting survey.

Your travel management company holds the best data. Ask for a report covering the period with, per trip:

Most providers produce this as a standard report. Ask for it before you try to build it from expense claims.

Avarni calculates flight distance from the airport pair. You do not need to provide distances.

Upload a start airport and an end airport per flight, and mark whether it was a return trip.

Three things affect the factor:

Haul length. Short, medium and long haul have different factors per kilometre. A single average factor across all flights overstates short haul and understates long haul.

Cabin class. Business and first class carry higher factors, because a passenger takes more of the aircraft.

Radiative forcing. Aviation at altitude has effects beyond CO2. Many factor sets offer a version with and without a radiative forcing uplift. Choose one, apply it consistently, and record which.

Calculated from room nights, using a factor per night that varies by country.

If you only have spend, use a spend-based factor and note it. Room nights are much better and most travel providers have them.

Hire cars are best calculated from distance. Taxis and rideshare are usually spend-based, since distance is rarely available. Rail is per passenger-kilometre where you have it.

Expense data gives you spend by category and little else.

Use spend-based factors and record that you did. Then ask whether your travel provider can give you activity data for next year, because this is one of the easier categories to improve.

Watch for two things in expense data. Personal travel reimbursed by mistake, and mileage reimbursement for an employee's own car, which belongs with fuel rather than here.

Use a Method configured for distance and the flight distance calculator. The upload then asks for the start and end airports instead of an amount.

For accommodation and ground travel, upload the quantity against a Method for each.