In her new role, Armitage will lead the agency sales team that sells advertising across Heathrow, London Luton, Glasgow, Edinburgh and Aberdeen airports, as well as the Eurotunnel and the Heathrow Express.
Armitage will report to Alan Sullivan, sales director of JCDecaux Airport.
Sullivan said: "This is a key time for the business as we prepare to launch a broad range of product enhancements, made possible by our recent successful BAA contract re-tenders."
In May, BAA confirmed the winners in the tender for its outdoor contracts and JCDecaux retained four of the seven contracts.
Sullivan said: "Nicola’s experience and excellent agency relationships will help us to maximise this opportunity."
Armitage moved across to JCDecaux under TUPE [Transfer of Undertakings (Protection of Employment)] regulations, following the company's purchase of the Titan Outdoor assets in January.
She had worked at Titan Outdoor since 2007, and was group head of planning for WPP out-of-home agency, Kinetic.
Prior to joining Titan, Armitage worked at outdoor media owner Clear Channel Outdoor as an account manager. She started her career in display sales at News International.
In April JCDecaux Airport entered into consultation with three members of staff, including marketing director Richard Malton and a two senior sales people.