The size of Mount Barker Summit is approximately 8.3 square kilometres. The population of Mount Barker Summit in 2011 was 340 people. By 2016 the population was 105 showing a population decline of 69.1% in the area during that time. The predominant age group in Mount Barker Summit is 10-19 years. Households in Mount Barker Summit are primarily couples with children and are likely to be repaying $2400 - $2999 per month on mortgage repayments. In general, people in Mount Barker Summit work in a managers occupation. In 2011, 83.9% of the homes in Mount Barker Summit were owner-occupied compared with 71.5% in 2016.