A total of 51 original members (or founding members) joined that year; 50 of them signed the Charter at the United Nations Conference on International Organization in San Francisco on 26 June 1945, while Poland, which was not represented at the conference, signed it on 15 October 1945.
Sebanyak 51 anggota asli (atau anggota pendiri) bergabung pada tahun tersebut; 50 diantaranya menandatangani Piagam tersebut di Konferensi Perserikatan Bangsa-Bangsa tentang Organisasi Internasional di San Francisco pada 26 Juni 1945, sementara Polandia, yang tidak terwakili di konferensi tersebut, menandatanganinya pada 15 Oktober 1945.