Williams qualified for the
2020 BDO World Darts Championship as one of the Playoff qualifiers. He defeated
Wes Newton and
Andrew Kateley to secure his place in the tournament. He was
whitewashed 3–0 by
Justin Thompson in the preliminary round. In 2022, Williams won his first PDC Challenge Tour title at
Challenge Tour 1 in
Milton Keynes. On his way to the final, Williams defeated
Conor Heneghan in the last 64,
Jimmy Bristow 5–1 in the last 32,
Darryl Pilgrim 5–2 in the round of 16, Darren Johnson 5–3 in the quarter-finals and
Danny Lauby Jr. 5–1 in the semi-finals. He defeated
Robert Owen in the final 5–2. Later the same day, Williams won his second Challenge Tour title at
Challenge Tour 2. Williams won 5–2 against
Lee Evans in the final. On the
2022 PDC Pro Tour, Williams received call–ups for
2022 PDC Players Championship series events filling in as a reserve for an absent tour card holder virtue of his ranking on the Challenge Tour Order of Merit. Williams won
Players Championship 17 in June, beating
Nathan Aspinall 8–5 in the final. This meant he became the third player, after
Joe Murnan and
Krzysztof Ratajski, to win a Players Championship event without being a PDC Tour Card holder. At the end of September 2022, he was selected by the national federation to participate in the
2022 WDF Europe Cup. On the second day of the tournament, he advanced to the finals of the pairs competition where he played together with
Joshua Richardson. On the way to the final, they defeated rivals from Wales, Romania and Czech Republic. Finally, on 1 October, they beat Polish duo
Sebastian Białecki and
Dariusz Marciniak 6–2 in legs. He also won a gold medal in the men's team event, as well as contributing to England's overall gold medal. Williams finished 2022 with four Challenge Tour titles. He topped the
2022 Challenge Tour Order of Merit, securing qualification for the
2022 Grand Slam of Darts, his debut at the tournament. He also secured a debut at the
2023 PDC World Darts Championship, but was already qualified via the Pro Tour Order of Merit. At the Grand Slam, he finished third in his group and was eliminated. At the World Championship, he won his opening match against
Ryan Joyce 3–1 with an average of 100.32. In the match, Williams and Joyce broke the record for number of 180s hit in a first-round World Championship match, with 17 between them. Williams lost to
Rob Cross 3–1 in the second round. Williams played his first year as a PDC Tour Card holder in 2023. He reached the semi-finals of the
2023 Hungarian Darts Trophy, missing out on the final by losing to eventual champion
Dave Chisnall 7–5. At the
2024 PDC World Championship, Williams beat
Haruki Muramatsu 3–1 in the first round before eliminating seventh seed
Danny Noppert in the second round, defeating Noppert 3–0. Williams caused controversy following his next win over
Martin Schindler, joking about England winning "two
World Wars and one
World Cup" after his victory against his German opponent.
Sky Sports apologised for Williams' remarks on the air and Williams later apologised himself, calling the comment 'stupid'. In the quarter-finals, Williams faced three-time World Champion
Michael van Gerwen. Williams managed a surprise win over van Gerwen, defeating him 5–3 to progress to his first major semi-final. Williams' run came to an end when he was
whitewashed 6–0 by eventual champion
Luke Humphries. Williams found form again at the
2024 Players Championship Finals, earning victories over
Gian van Veen,
Kim Huybrechts and
Jeffrey de Graaf to reach the quarter-finals, where he lost to
Ross Smith 10–3. At the
2025 PDC World Darts Championship, Williams defeated
Niko Springer 3–1 in the first round. He played
Rob Cross in a rematch of their 2023 meeting, but this time Williams beat the former World Champion 3–1. Williams lost to
Ricardo Pietreczko 4–1 in the third round. ==World Championship results==