He was welcomed by the Polish ambassador to the UK, Piotr Wilczek, and POSK Chairman Marcin Kalinowski.
During his visit, the king toured an exhibition of paintings by Polish artist and World War II veteran Felix Fabian.
The collection depicted scenes from Fabian’s homeland in Poland, his travels along the combat route of the Second Polish Corps in the Middle East and Italy, his postwar life in Argentina, and his eventual settlement in London.
The British monarch also attended a community reception, where he met 102-year-old D-Day veteran Eugeniusz Niedzielski, as well ass representatives from various Polish organisations, business leaders, social workers, teachers and folk dance performers.
The programme of the visit included a Chopin recital by young Polish pianist Anita Łozińska and a performance of popular Polish songs by a group of young members of POSK Theatre.
According to the POSK website, "the atmosphere was friendly and relaxed and there were no formal speeches."
King Charles had previously visited POSK as the Prince of Wales in 2010, accompanied by Queen Camilla, then the Duchess of Cornwall.
Founded more than half a century ago, POSK serves as a cultural and social hub for the Polish community in the UK.
(mk/gs)