The size of Ob Flat is approximately 25.7 square kilometres. It has 1 park. The population of Ob Flat in 2011 was 631 people. By 2016 the population was 420 showing a population decline of 33.4% in the area during that time. The predominant age group in Ob Flat is 60-69 years. Households in Ob Flat are primarily childless couples and are likely to be repaying $1800 - $2399 per month on mortgage repayments. In general, people in Ob Flat work in a managers occupation. In 2011, 86.2% of the homes in Ob Flat were owner-occupied compared with 86.7% in 2016. Currently the median sales price of houses in the area is $555,000.