The size of Semaphore Park is approximately 2.1 square kilometres. It has 15 parks covering nearly 13.1% of total area. The population of Semaphore Park in 2011 was 4,225 people. By 2016 the population was 4,312 showing a population growth of 2.1% in the area during that time. The predominant age group in Semaphore Park is 60-69 years. Households in Semaphore Park are primarily childless couples and are likely to be repaying $1800 - $2399 per month on mortgage repayments. In general, people in Semaphore Park work in a professional occupation. In 2011, 54.5% of the homes in Semaphore Park were owner-occupied compared with 54.1% in 2016. Currently the median sales price of houses in the area is $621,000.