Born in Nottingham, she attended Warwick University, where she graduated with an English and Theatre degree. Her first job was as a researcher for Germaine Greer and she then worked as the script editor on the revamped Crossroads until 2003. She then produced The Archers for seven years until 2010. Her next role was as story editor on Emmerdale, then producer for the same programme for four years, with a short period in-between (from 2012 to 2013) as assistant producer of Coronation Street.
During her time as producer, Kate reintroduced Peter Barlow, Adam Barlow, Brian Packham, Toyah Battersby, Rosie Webster and Carla Connor to the show, as well as the short returns of Denise Osbourne, Rob Donovan and Martin Platt.
Major plots in her run involved issues which received criticisms from some quarters due their dark nature, including Bethany Platt's grooming, David Platt's male rape and Pat Phelan's murder of several characters.
Kate Oates also saw the show go under two big changes, with an extra episode a week being added and the extension of the set, with Victoria Street being extended. Kate also had to deal with two sackings from the show, which led to quick rewrites, refilming and reediting. In September 2016, Marc Anwar was sacked from his role as Sharif Nazir due to racist tweets, which led to his character running away. In October 2017, Bruno Langley was sacked for sexual assault, which meant that Todd Grimshaw assaulted a police officer off-screen and went on the run.