DemographicsSidmouth is approximately 23.67 square kilometres. In 2016 the population of Sidmouth was 394. The population is 53% male and 47% female. On average the monthly mortgage repayments in Sidmouth are $1000 to $1399. The most common weekly income bracket is $500 to $649 per week. Weekly rents in the area are on average $100 to $149.