While we're waiting for Season 4 ... The Handmaid's Tale gets renewed for a fifth season!
"We’re very grateful to Hulu and MGM that the show will be returning for a fifth season, and especially to our loyal fans for their support,” said Miller, who serves as showrunner. “We are thrilled to be able to continue to tell these stories, with our incredible cast and crew, and can’t wait to be back on the air with season four next year.” - via The Hollywood Reporter
Season 4 does not have a premiere date, but will be released sometime in 2021.