The six-month deal will run from 7 January to 7 July and the creative will centre on the message, "Keeping you moving, whatever it takes".
Absolute Radio will also run sponsorship trails for a series of 'Pit Stops' Green Flag is running around the UK, where it will offer public tutorials on changing oil, water and general advice on vehicle maintenance.
A brand takeover of the Traffic and Travel page on the Absolute Radio website is also part of the sponsorship package.
Lauren Croly, senior planner and buyer of investment at MediaCom, and Emma Smyth, head of sponsorship at Absolute Radio, brokered the deal.
Green Flag's sponsorship ties in with its brand promise that it will arrive on the scene of an emergency within 60 minutes, with customers receiving 50% off their next renewal if the promise is not fulfilled.
Creative for the sponsorship has been handled by CHI & Partners and tells the story of a man who breaks down as he tries to make it home in time for his child's bath time.
The deal follows December's news that Absolute Radio owner Bennett, Coleman & Co has re-entered discussions with potential buyers, after calling off a sale last year.Follow @mattchapmanuk