The 24-year-old Masterton woman was arrested on Thursday and bailed to appear in the Masterton District Court next week.
Police were continuing their inquires, Mr Rackliff said.
A spokeswoman for Wellington Airport said the airport was aware of the theft and was assisting police, but declined to make any further comment.
Hertz, Avis and Thrifty Car Rentals were reluctant to comment when approached by the Times-Age.
A Hertz spokesman said he was unaware of anything similar happening before, adding people returning rental cars needed to be sure the person they handed keys over to was a company employee. Hi-vis vests worn by rental car company employees tended to have a company logo on them.