Thomas David Simpson (born 16 February 1959) is a Democratic Unionist Party (DUP) politician in Northern Ireland, who was the Member of Parliament (MP) for Upper Bann from 2005 to 2019.

In the 2001 general election Simpson stood unsuccessfully against Ulster Unionist Party leader David Trimble in the parliamentary constituency of Upper Bann.

He is a proponent of creationism,[5] and his former election agent and constituency assistant, David McConaghie, who had played a key role in Simpson's 2005 election victory, was until late 2012 a prominent spokesperson for the Caleb Foundation which represented creationist and socially conservative Evangelical Protestant views.

In 2018, after 30 years of marriage, Simpson reportedly left his marital home after allegations of his having an affair were published in a newspaper.

[11] The husband was later sacked for "gross misconduct" from his employment as a sales executive with the meat company owned by Simpson and his wife.