After the penultimate episode airs, fans of the show will be able to cast votes via the website to determine the outcome of a love triangle between Gaz, Janet and Donna.
Two endings will be filmed and the storyline with the highest number of votes will be aired as the finale to series eight, with the alternative ending available to view online.
"We want to make sure we keep innovating when it comes to schedule favourites as well as new programmes on BBC Three," said channel controller Danny Cohen.
"The last series of Two Pints included a live episode. For this series we're going to use interactivity to put viewers in charge of the plot."
The series finale will air on BBC Three on Sunday, May 10.