The size of Wellesley is approximately 50 square kilometres. The population of Wellesley in 2011 was 399 people. By 2016 the population was 48 showing a population decline of 88.0% in the area during that time. The predominant age group in Wellesley is 10-19 years. Households in Wellesley are primarily childless couples and are likely to be repaying $1800 - $2399 per month on mortgage repayments. In general, people in Wellesley work in a sales workers occupation. In 2006, 14.3% of the homes in Wellesley were owner-occupied compared with 53.5% in 2011.