She began her career working as a researcher and editorial assistant for Germaine Greer, before becoming a script editor for the soap opera Crossroads.

After leaving Emmerdale, Oates transferred to Coronation Street as the series producer, a move which was praised by ITV personnel.

Oates' hiring by the BBC as the senior executive producer of EastEnders, Casualty and Holby City was announced in August 2018.

[6] Oates' work on Crossroads lead her to begin producing BBC Radio 4 soap opera, The Archers, a place which she credits as the "bulk of her training".

[2] Oates began working on the ITV soap opera Emmerdale in early 2010 as a story editor, under then-producer, Gavin Blyth.

[5] Reflecting on Oates' work on the show as story editor, John Whiston, the creative director of ITV soaps, commented, "Kate swept into Emmerdale a couple of years ago with a deadly combination of determination and brio.

[12] Oates focused on major storylines such as Brenda Walker's (Lesley Dunlop) brain tumour, Cameron Murray's (Dominic Power) killing spree and Rhona Goskirk's (Zoe Henry) painkiller addiction.

[10] Cameron's killing spree culminated in a siege set in The Woolpack pub, a central location of the series.

[14] During her time at Emmerdale, Oates introduced many well publicised storylines, including Donna Windsor's (Verity Rushworth) "heart-wrenching" battle with terminal cancer,[15] Laurel Thomas' (Charlotte Bellamy) "dark" alcoholism story,[16] Aaron Livesy's "tear-jerking" and "tragic" revelation that he was sexually abused by his father as a child,[17] a week of episodes involving a helicopter crash and the deaths of two regular characters,[18][19] as well as the popular pairing of Robert Sugden (Ryan Hawley) and Aaron Livesy, which Duncan Lindsay of the Metro opined had "defined" her era.

She also reintroduced former characters Leyla Harding (Roxy Shahidi), Donna Windsor (Rushworth), Aaron Livesy (Miller) and Douglas Potts (Duncan Preston) for regular stints,[25] as well as Steph Stokes (Lorraine Chase), Paul Lambert (Matthew Bose) and Nikhil Sharma (Rik Makarem) for guest stints.

[29] John Whiston praised Oates' work on the show, opining that she had made Emmerdale popular again and given it an "on-going resurgence".

[29] He added, "She has that rare combination, a sharp editorial eye for a compelling story together with deep understanding of what drives characters caught up in such drama.

[34][35] She also reintroduced Toyah Battersby (Georgia Taylor), following a 14-year absence, Rosie Webster (Helen Flanagan), Brian Packham (Peter Gunn) and Carla Connor (Alison King).

[37] At a show press event, Oates explained that she wanted to introduce a "greater breadth of storylines" and use more of the soap's talented cast.

[38] Michelle Connor (Kym Marsh) and Steve McDonald's (Simon Gregson) "devastating" late miscarriage,[39] Ken Barlow's (William Roache) stroke and attempted murder,[40][41] Bethany Platt's (Lucy Fallon) "brave and dark" sexual exploitation story,[42] David Platt's (Jack P. Shepherd) "controversial" rape at the hands of Josh Tucker (Ryan Clayton),[43] and Aidan Connor's (Shayne Ward) "haunting" suicide.

We are now used to opening the overnights and seeing Coronation Street has delivered its highest ratings for many years, a herculean achievement in this box set era.

[45] He commended her "groundbreaking and socially important stories", including Pat Phelan's villainous spree and the light-hearted humour between characters.

[47] After leaving Coronation Street, Oates was announced to be joining Tall Story Pictures, a company owned by ITV Studios.

[45] In August 2018, it was announced that Oates would become the senior executive producer of EastEnders as well as BBC medical dramas Casualty and Holby City.

[48] Initially, Oates primarily worked with the team at EastEnders alongside the show's executive consultant, John Yorke from October to December 2018 to provide a "smooth handover".

She commented, "I'm excited about meeting the teams and talent behind each show and can't wait to get stuck in and tell some unmissable stories.

[52] In April 2019, it was announced that Oates had been promoted to Head of Continuing Drama at BBC Studios, succeeding Oliver Kent.

[53] Oates continues to be based at the filming studios of EastEnders, BBC Elstree Centre, and works closely with their production team.

[53] Ralph Lee, the director of content at BBC Studios, praised Oates, branding her "an exceptional talent".

[53] He observed, "Kate's passion and creativity is already making a real difference and she can now apply her exciting vision to the full portfolio of our continuing dramas.