British Airways has started offsetting all carbon emissions from its domestic flight programme.
It comes after owner IAG last year pledged to achieve net zero carbon emissions by 2050.
BA says emissions from flights within the UK will be offset by investment in "high quality, verified" carbon reduction projects around the world.
These include renewable energy developments, rainforest protection and reforestation efforts.
BA operates up to 75 flights a day between London and 10 UK destinations including Manchester, Leeds, Newcastle, the Isle of Man, Edinburgh, Glasgow, Aberdeen, Belfast City, Inverness and Jersey.
Carbon reduction efforts across BA’s operations will extend to investing in more fuel-efficient aircraft and sustainable aviation fuels, and modernising operating procedures.
IAG has also pledged to invest £400 million in development of sustainable aviation fuels over the next 20 years through its partnership with Velocys.
BA chairman and chief executive Alex Crus said: "Solving the complex issue of climate change requires a multi-faceted response, and offsetting emissions on all flights within the UK is just one step we are adopting to reduce our environmental impact while more solutions to decarbonise are found.
"Our emissions reductions projects are carefully chosen to ensure they are proven and deliver real carbon emissions reductions as well as economic, social and environmental benefits."
Cruz added BA was investing in aircraft offering 25% to 40% better fuel efficiency than those they replace.
Customers flying further afield can calculate the likely emissions impact and offset them through BA’s partnership with not-for-profit Pure Leapfrog.
Offsetting starts from around £1 on a return London-Madrid flight, and £15 for a business class London-New York flight.