Findlay fills the position left vacant by Chris Kennedy who announced his departure for UK chip designer ARM at the start of the year.
It's the second time a senior executive has been poached from Halfords after Tesco nabbed chief executive Matt Davies in January.
Findlay will remain at the bike retailer until the end of October as a search for a successor begins.
"I and the EasyJet team are delighted to welcome Andrew as CFO," said EasyJet chief exec Carolyn McCall.
"He is a proven FTSE 250 CFO with great consumer experience and a strong focus on cost. He is part of the leadership team at Halfords which has created a much more customer-centric and profitable business. Andrew is a great fit for EasyJet and I am sure he will add a lot of value to the airline."