Minimum wage in Montana will increase on January 1st Posted at 11:00 AM, Dec 30, 2020 and last updated 2020-12-31 09:47:51-05 GREAT FALLS â Montanaâs minimum wage will increase from $8.65 per hour to $8.75 per hour beginning on Friday, January 1, 2021. The state reports that an estimated 8,000 to 10,000 Montana workers, or about two percent of the workforce, received hourly wages less than $8.75 per hour in 2020. At the beginning of 2020, the minimum wage in Montana was raised from $8.50 to $8.65. The minimum wage is determined by taking the current minimum wage of $8.65 and increasing it by the CPI-U increase from August of 2019 to August 2020. The CPI-U increased by 1.31% (unadjusted) over the year ending August 2020.