He debuted on 6th September 2018 in the champion's chair, securing his first victory with a score of 95 points against Joe Harris. He then put on 7 more impressive victories to become the series' third consecutive octochamp and will return for the finals, for which he is provisionally ranked as the #5 seed. During his heat run, he defeated Laura McDonald, the mother of Series 78 finalist Toby McDonald.
With the withdrawal of Robin Johnson, Ashton faced Tony Manwani in the 4th Quarter Final as the #4 seed. In the game, Ashton put in a good performance, particularly on the numbers, but was outplayed in the end by Manwani, who scored the maximum possible in 11 out of 15 rounds, meaning that it did not fall true to seeding.
|#||Date||Type||Contestant 1||Score||Contestant 2||Guest||Lex||Max|
|6904||6/09/2018||P||Dave Ashton||95 – 68||Joe Harris||Mark Pougatch||Susie Dent||134|
|6905||7/09/2018||P||Dave Ashton||105 – 34||Tricia Lea||Mark Pougatch||Susie Dent||134|
|6906||10/09/2018||P||Dave Ashton||84 – 49||Dan Martin||Mark Pougatch||Susie Dent||125|
|6907||11/09/2018||P||Dave Ashton||82 – 62||David O'Neill||Charlie Stayt||Susie Dent||135|
|6908||12/09/2018||P||Dave Ashton||87 – 36||Kim Wilson||Charlie Stayt||Susie Dent||134|
|6909||13/09/2018||P||Dave Ashton||87 – 47||Laura McDonald||Charlie Stayt||Susie Dent||121|
|6910||17/09/2018||P||Dave Ashton||100 – 78||Stephen Holford||Charlie Stayt||Susie Dent||126|
|6911||18/09/2018||P||Dave Ashton||99 – 58||Mark Garfield||Charlie Stayt||Susie Dent||142|
|6976||18/12/2018||QF||Dave Ashton||79 – 114||Tony Manwani||Phill Jupitus||Susie Dent||129|