The size of Llanarth is approximately 2.4 square kilometres. The population of Llanarth in 2011 was 1,754 people. By 2016 the population was 2,193 showing a population growth of 25.0% in the area during that time. The predominant age group in Llanarth is 10-19 years. Households in Llanarth are primarily couples with children and are likely to be repaying $1800 - $2399 per month on mortgage repayments. In general, people in Llanarth work in a professional occupation. In 2011, 80.3% of the homes in Llanarth were owner-occupied compared with 82.1% in 2016. Currently the median sales price of houses in the area is $628,250.