York's first professional job was a Braun ThermoScan Ear Thermometer commercial when she was eight months old. At the age of 9 she got an agent and started going out on auditions and consistently receiving call-backs. Her first film role was the part of Kim Baker in the box-office hit Cheaper by the Dozen and then headed to Toronto the following summer (2004) to film The Pacifier in the role of LuLu Plummer. The next summer (2005), York headed back to Toronto to film Cheaper by the Dozen 2. In 2006–2010 York appeared in 11 episodes of Disney's Hannah Montana. York has posted on her blog that she stopped acting in 2010, after Hannah Montana's fourth season finished production. She stated she will not return to acting in the future.
York stopped acting at age 17, after she lost interest. On her personal website she has stated that her days on set of Hannah Montana were spent reading books and she was not enjoying acting the way she used to, she also wrote an article on the darker side to being a child actor. York graduated a literature course at University of Redlands in 2015 and is currently working on publishing Young Adult books which she has written .