Thomas served as a
Conservative Party councillor on
Barnet London Borough Council from 2006 to 2025, serving as leader of the council from 2019 to 2022, and as leader of the opposition Conservative group on the council following 2022. In the
2010 and
2017 general elections, he was the Conservative parliamentary candidate for
Islwyn, coming second both times. In the
2016 London Assembly election, he stood as the Conservative candidate for
Barnet and Camden. In 2018 while Dan Thomas was deputy council leader of Barnet, he and the council leader faced calls to resign from the leader of the Labour group on the council, after it came to light that a council worker, who was sentenced to 5 years in prison, had stolen £2 million by fraud from the council while working with
Capita between 2016 and 2017. Following the birth of his son in summer 2024, he moved away from Barnet and announced he would be standing down from the council in the following year. Dan Thomas defected to
Reform UK in June 2025, stating: "I joined Reform because of their unwavering commitment to defending British culture, identity, and values." He later resigned from the council on 31 December 2025, leaving a vacant seat heading into the
2026 election; the timing of the resignation meant a by-election was avoided.
Leadership of Reform UK Wales Thomas was announced as Leader of Reform UK Wales on 5 February 2026. Following speculation in the media about where Thomas lived, Reform UK said: "Dan lives in Wales. Any claim to the contrary is entirely false. He lives here in Wales, where he is raising his young family". They also confirmed that he owns a property portfolio, which included a property in Bath that is rented out and not his main residence. ITV Wales confirmed they had seen proof that Dan Thomas was added to the electoral roll in the Caerphilly borough area in July 2025. A Reform UK spokesperson said: "Dan is on the electoral roll here in Wales". Following a series of controversies relating to the party's selections, Thomas appointed
Helen Jenner as the party's deputy leader. == Personal life ==