The independent agency fought off competition from Grey in the final round, as well as VCCP in an earlier stage of the process, which was run by AAR.
The hotel chain put its ad account up for review in February. It was the first time the brand had reviewed its advertising since appointing Rainey Kelly Campbell Roalfe/Y&R in 2007.
RKCR/Y&R, which did not repitch for the business, brought in Lenny Henry as Premier Inn’s brand spokesman.
Lucky Generals will start work on the account immediately in advance of a campaign to break later this year.
Mark Fells, the chief marketing officer at Premier Inn, said in a statement: "Although this was a competitive pitch process, Lucky Generals were the stand out agency showing a great understanding of where the brand is moving strategically. The chemistry with the team and their amazing success over only a three year period, as well as their fantastic creative insight cemented the decision. We are really excited to begin our partnership with them.
"Over the last nine years RKCR have helped us create many award-winning campaigns and were instrumental to their success. I’d like to thank them for all their hard work and support and wish them all the best for the future."
Helen Calcraft, one of the founders of Lucky Generals, added: "Premier Inn is an extraordinarily successful business, with a great brand and product. We've been bowled over by the team's ambition and their desire for impactful advertising and we can't wait to get working with them."