At the 2012 Summer Olympics in London, Almeida qualified for the men's 100 m breaststroke by establishing a Portuguese record and achieving a FINA B-standard entry time of 1:01.19 from the European Championships in Debrecen, Hungary. He challenged seven other swimmers on the third heat, including fellow two-time Olympian Martin Liivamägi of Estonia. He raced to third place by two tenths of a second (0.20) behind Greece's Panagiotis Samilidis in 1:01.40. Almeida failed to advance into the semifinals, as he placed twenty-fifth overall out of 44 swimmers on the first day of preliminaries.