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Polymyxin resistance, determined by <i>mcr</i> genes located on plasmid DNA, currently poses a high epidemiological threat. Non-typhoid <i>Salmonella</i> (NTS) are one of the key pathogens causing diarrheal diseases. Here, we report the isolation and whole genome sequencing of multidrug colistin-resistant/susceptible isolates of non-typhoid <i>Salmonella enterica</i> serovars carrying <i>mcr</i> genes. Non-typhoid strains of <i>Salmonella enterica</i> subsp. <i>enterica</i> were isolated during microbiological monitoring of the environment, food, and diarrheal disease patients between 2018 and 2020 in Russia (<i>n</i> = 586). <i>mcr-1</i> genes were detected using a previously developed qPCR assay, and whole genome sequencing of <i>mcr</i> positive isolates was performed by both short-read (Illumina) and long-read (Oxford Nanopore) approaches. Three colistin-resistant isolates, including two isolates of <i>S</i>. Enteritidis and one isolate of <i>S</i>. Bovismorbificans, carried the <i>mcr-1.1</i> gene located on IncX4 and IncI2 conjugative plasmids, respectively. The phenotypically colistin-susceptible isolate of <i>S</i>. Typhimurium carried a <i>mcr-9</i> gene on plasmid IncHI2. In conclusion, we present the first three cases of <i>mcr</i> gene-carrying NTS isolates detected in Russia with both outbreak and sporadic epidemiological backgrounds.