Antoinette Geraldine Mackeson-Sandbach (born 15 February 1969), known as Antoinette Sandbach, was a British politician who was elected as the Member of Parliament for Eddisbury in Cheshire at the 2015 general election.
The following day, 8 May 2015, she resigned as the Welsh Assembly Member for the North Wales region, having been elected as a North Wales regional Assembly Member at the May 2011 election.
First elected as a Conservative, Sandbach had the Conservative whip removed on 3 September 2019 and later lost a vote of no confidence by the Eddisbury Conservative Association.
Following deselection as a Conservative, Antoinette Sandbach chose eventually to become a Liberal Democrat.
She lost her seat to her former party in the 2019 general election.