Points-based travel reward programme Buy and Fly! will pay for at least 20 flights made by Comic Relief's staff to monitor international projects this year as part of a two-year corporate tie-up.
The link-up is set to be worth "tens of thousands of pounds" and will greatly cut the time the charity spends finding cheap flights.
"We buy a minimum of 20 essential flights to monitor and evaluate our projects every year," said Alison Scott, the charity's media manager.
"Finding the cheapest flights can often take a day to sort out, so having a flight partner who can help us with those is fantastic."
Comic Relief makes around 50 more flights for monitoring and for film crews to make documentaries, which are usually paid for by grants and corporate donors.
This is the first major charity partnership for Buy and Fly! and its operator Landround, which previously helped various good causes in north-west England.
"We chose Comic Relief because its supporter profile closely matches our target audience, enabling us to maximise the amount we can raise for them," said David Lyne, Landround's chief executive. "As the charity operates abroad, this will enable us to support its causes by offering tens of thousands of pounds worth of flights," added Lyne.
Customers collecting Buy and Fly! points will also be able to donate them when they shop the scheme's retail partners, which include Domino's Pizza, Odeon Cinemas and the RAC.
Everyone who registers online with Buy and Fly! will receive 100 free points - enough for a ferry trip to Ireland or France for five people for five days - which can be donated to Comic Relief for further flights.
Customers can also donate their points to Comic Relief when they call the company's enquiry line to find out how many points they can redeem.