DemographicsThalgarrah is approximately 354.74 square kilometres. In 2016 the population of Thalgarrah was 178. The population is 54% male and 46% female. On average the monthly mortgage repayments in Thalgarrah are $0 to $299. The most common weekly income bracket is $800 to $999 per week. Weekly rents in the area are on average $200 to $224.