The event is scheduled to take place in the Main Proms Arena on Lytham Green from Wednesday, June 30 to Sunday, July 4.
Festival director Peter Taylor of promoter Cuffe & Taylor said: “We are so incredibly excited to be announcing our full line-up for Lytham Festival 2021. Lionel Richie and Diana Ross are two of the world’s most iconic artists, there is no bigger British artist right now than Lewis Capaldi, and in Snow Patrol we have one of the most influential bands of the last 20 years. Duran Duran are global superstars.
"It is no secret that a massive amount of Lytham Festival fans have been asking for them to perform on our lovely Green for more than 10 years, so we can’t wait to welcome them and the whole of this incredible line-up to wonderful Leafy Lytham.”
Other acts on the festival bill include Jack Savoretti, Craig Charles, Gloria Gaynor, TLC, Luke La Volpe and Jade Bird, with further artists to be annonced.
Taylor added: “Live music and entertainment is part of the beating heart of the UK and we plan to make Lytham Festival bigger and better than ever before for 2021.
“We have a line-up filled with world-class artists and really cannot wait for June 30 when can all celebrate together and return to Lytham Green.”
Five-day passes are on sale now, with individual tickets on sale at 8am on Friday, October 30.