**Background:** One in three Australian children are overweight or obese, and the majority do not consume a diet consistent with Dietary Guidelines. Frequent intake of discretionary foods such as fast-food is a major contributor. Having unhealthy food environments near schools can adversely affect diet quality and be a driver of obesity in schoolchildren. A prior Western Australian study found almost half (45%) of secondary students purchased discretionary foods from outlets near their school weekly or more, and purchase frequency was significantly associated with the availability of major fast-food outlet chains near the school. Despite state priorities calling for changes to planning laws to limit unhealthy food outlets near schools, no detailed local evidence existed to benchmark and guide implementation in Perth, Western Australia.
**Methods:** A listing of all schools (n=655) in the Perth metropolitan area in 2019 was obtained from the WA Education Department, comprising primary (n=454, 69.3%), secondary (n=107, 16.3%), and K-12 (n=94, 14.4%) schools. Fast-food outlet locations were sourced from each Perth Local Government between May 2018 and July 2019. Fast-food outlets were defined as outlets where food is ordered at the counter, served immediately, and can be eaten without cutlery. A separate sub-variable distinguished the 'Top 4' most frequented fast-food chains (McDonald's, KFC, Hungry Jack's, and Red Rooster). Schools were allocated a suburb-level disadvantage decile ranking using the Australian Bureau of Statistics Socio-Economic Index for Areas (SEIFA) Index of Relative Socio-Economic Disadvantage, where decile 1 indicates greatest disadvantage and decile 10 indicates least disadvantage. Counts of fast-food outlets and 'Top 4' chains within Euclidean buffers of 400 m, 800 m, and 1 km around schools were calculated. Logistic binomial regression assessed whether availability differed by school type, and negative binomial or Poisson regression calculated incidence rate ratios to assess differences by school SES (low vs high).
**Key Results:** Ninety-seven percent of secondary schools had one or more fast-food outlet within 1 km, with an average of 12.6 outlets per school. About half of secondary schools (51%) had access to more than one 'Top 4' chain within 1 km, compared to 39% of primary and 36% of K-12 schools. Nearly half of all schools (44.4%) had at least one fast-food outlet within 400 m. Secondary schools were significantly more likely than primary and K-12 schools to have more fast-food outlets within 400 m (OR 0.54, 95% CI 0.36-0.81 for primary vs secondary), 800 m (OR 0.55, 95% CI 0.42-0.72), and 1 km (OR 0.57, 95% CI 0.45-0.72), and more 'Top 4' chains within 800 m and 1 km. There were 174 schools (26.6%) located in low SES areas (SEIFA deciles 1-3) and 254 schools (38.8%) in high SES areas (deciles 8-10). Schools in low SES areas had a significantly higher density of fast-food outlets within 400 m (IRR 1.32, 95% CI 1.02-1.71) and 'Top 4' chains within 400 m (IRR 1.86, 95% CI 1.30-2.65) and 1 km (IRR 1.64, 95% CI 1.23-2.18) compared to schools in high SES areas.
**Clinical Implications:** The findings demonstrate that Perth schools are surrounded by fast-food outlets, with significantly higher densities around secondary schools and schools in lower SES areas. One in seven secondary schools (14%) had at least one 'Top 4' chain within 400 m (less than a 5-minute walk). This is consistent with prior Australian research finding 13% of Victorian secondary schools had a 'Top 4' chain within 500 m. The socio-economic disparity in fast-food outlet availability suggests vulnerable populations are at heightened risk of developing poor eating habits. Currently in Western Australia, 'public health' is not deemed a relevant planning consideration under the Planning and Development (Local Planning Schemes) Regulations 2015. The authors recommend amending Regulation 67 of Schedule 2 to include public health considerations, which would enable local governments to introduce exclusion zones with prescribed minimum distances for fast-food outlets near schools. Australia currently has no examples of fast-food zoning restrictions near schools, unlike the United Kingdom, United States, Ireland, and South Korea which have introduced such restrictions. The study's limitations include its cross-sectional design, focus on a single Australian city, and lack of adjustment for population density or assessment of all food outlet types. Nevertheless, the study provides benchmarking data to guide policies aimed at improving the healthfulness of food environments surrounding schools.