The 23-year-old, who rides for the Deceuninck-Quick Step cycling team, beat Slovenia's Matej Mohorič by 20 seconds overall in the seven-stage 1,140 km race.
Polish rider Michał Kwiatkowski, who won the 2018 Tour de Pologne, placed third in the final standings, 27 seconds behind Almeida.
Julius van den Berg of the Netherlands won the last, 145.1 km, leg of the race, which ended in the historic city of Kraków on Sunday.
Poland's Łukasz Owsian was the best climber in the annual race, which was held for the 78th time, attracting more than 150 riders from 22 teams based in various countries.
(gs)
Source: TVP, PAP