DemographicsMitchells Flat is approximately 34.77 square kilometres. In 2016 the population of Mitchells Flat was 209. The population is 47% male and 53% female. On average the monthly mortgage repayments in Mitchells Flat are $3000 to $3999. The most common weekly income bracket is $2000 to $2999 per week. Weekly rents in the area are on average $0 to $74.