Sophie Sinclair/Duncan Menzies (Stirling, SCO) qualified for the 2021 British Curling NCA Mixed Doubles Elite Finals playoffs, dropping their quarterfinals match 6-3 against Vicky Wright/Grant Hardie (Stirling, SCO). of the 2021 British Curling NCA Mixed Doubles Elite Finals in Stirling, Scotland;
 
Sinclair/Menzies finished 7-2 in the 0-team qualifying round. . In their opening game, Sinclair/Menzies defeated Jayne Stirling/Fraser Kingan (Stirling, SCO) 8-5, then won 8-3 against Eilidh Yates/Niall Ryder (Stirling, SCO). Sinclair/Menzies went on to lose 8-6 against Lauren Gray/Kyle Waddell (Stirling, SCO). Sinclair/Menzies responded with a 13-1 win over Nicola Joiner/Gregor Cannon (Stirling, SCO). Sinclair/Menzies won 9-7 against Jennifer Dodds/Bruce Mouat (Stirling, SCO). Sinclair/Menzies went on to lose 13-3 against Katie McMillan/Cameron Bryce (Stirling, SCO). Sinclair/Menzies responded with a 8-3 win over Holly Davis/Euan Kyle (Stirling, SCO). Sinclair/Menzies won 8-3 against Hailey Duff/Ross Whyte (Stirling, SCO), then won 7-4 against Rebecca Morrison/Hammy McMillan Jr. (Stirling, SCO) in their final qualifying round match.
 
Sinclair/Menzies ranks th overall on the Year-to-Date rankings with points earned so far this season.