The sweeping amnesty bill was initiated to mark the 20th anniversary of the establishment of the Russian constitution.
Under the bill, thousands of retirees, disabled people, women with children, pregnant women and victims of the Chernobyl disaster will be freed from prison, RIA Novosti reported. Precisely when they will be let out is unclear.
The law clears the way for Pussy Riot members Nadezhda Tolokonnikova, 24, and Maria Alyokhina, 25, to be freed from jail because they are both mothers of young children, RIA Novosti reported.
Alyokhina and Tolokonnikova are serving two-year prison sentences for hooliganism motivated by religious hatred for a performance by the punk rock collective against Russian President Vladimir Putin in Moscow's main cathedral in February 2012.
The final draft of the amnesty bill was also extended to include individuals still on trial and yet to be sentenced. That means the so-called "Arctic 30" Greenpeace members will also be saved from prison sentences.
The Greenpeace members were charged with hooliganism after trying to scale the side of an oil rig operated by the Russian energy giant Gazprom on Sept. 18.
The amnesty measure granted amnesty to retirees, invalids, women with children and pregnant women, and victims of the Chernobyl disaster. It does not include those convicted of terrorism-related offenses and sex crimes.
Notably, the harsh Kremlin critic Alexei Navalny, who was convicted of embezzlement earlier this year, will not be among those freed from prison.