Britain's slalom canoeist Lizzie Neave reached the kayak semi-finals with the second fastest time in the K1 heats at the Lee Valley White Water Centre.
The ex-World and European champion was fourth after the first run but improved by three seconds in the second.
Tim Baillie and Etienne Stott joined fellow Brits David Florence and Richard Hounslow in the C2 canoe semis.
Baillie and Stott finished fourth fastest, three places ahead of Florence and Hounslow.
Spain's Maialen Chourraut, who secured back-to-back World Cup wins earlier this season, was quickest in the women's K1.
France's Gauthier Klauss and Matthieu Peche topped the C2 standings, one place ahead of Peter and Pavol Hochschorner.
The Slovak twins are bidding for their fourth consecutive gold in the event.
The semi-finals and final of the C2 and K1 categories are on Thursday.