In July 2020, as part of the administrative reform of Ukraine, which reduced the number of raions of Mykolaiv Oblast to four, the city of Pervomaisk was merged into Pervomaisk Raion.
During a restructuring of Ukraine's administration in July 2020, the number of districts within Mykolaiv Oblast was reduced from multiple to four, and the city of Pervomaisk was integrated into the newly formed Pervomaisk District.