In February 1947, the Presidium of the Supreme Soviet of the USSR issued a resolution calling for the Soviet republics to adopt new flags, which each of its republics were recommended to develop and adopt new national flags.
All others followed suit between 1952 and 1953 with the last republic, the Russian SFSR, adopted the flag on 9 January 1954.
[1] Following the dissolution of the Soviet Union on 26 December 1991, only Kazakhstan, Kyrgyzstan, Tajikistan (without hammer and sickle), Turkmenistan and Ukraine retained their Soviet republic flags as independent states until the new official flags were adopted in 1992.
Since 1995 (current version adopted in 2012) Belarus retains its old Soviet flag with only minor changes.
Today, the only former Soviet Union territories that use modified versions of their original Soviet flag are the republic of Transnistria (a state of limited recognition, formerly part of the Moldavian SSR) and Belarus (since 1995).