The British Independent Film Award for Best Supporting Actress is a discontinued annual award given by the British Independent Film Awards (BIFA) to recognize the best supporting performance by an actress in a British independent film.
Since 2008, two categories named Best Supporting Actor and Best Supporting Actress are presented.
Olivia Colman is the only actress who has won this award more than once since its creations in 2008 with two wins while Kristin Scott Thomas and Julie Walters hold the record of most nominations in this category with three each.
In July 2022, it was announced that the performance categories would be replaced with gender-neutral categories, with both Best Supporting Actor and Best Supporting Actress merging into the Best Lead Performance category.
Additionally, a category named Best Joint Lead Performance was created for "two (or exceptionally three) performances that are the joint focus of the film, especially where performances share a large number of scenes and screen time".