Commuters will be reminded to support the Yorkshire Air Ambulance thanks to £100,000 worth of donated bus advertising.
Nearly 500 adverts promoting the rapid response charity are appearing on First Bus vehicles throughout Yorkshire after the space was donated by Exterion Media.
Yorkshire Air Ambulance needs to raise £9,990 every day to keep its two helicopters in the air.
Abby McClymont, marketing and communications manager for the charity, said: “The offer of advertising space from Exterion Media has been invaluable to us.
“Having nearly 500 of our adverts being driven across the Yorkshire region is just fantastic and is helping us to spread awareness about the work we do.”