The local food environment plays an important role in food purchasing behaviours, and it is important to understand the how this context shapes the highly complex drivers of food choice for children and families. In Australia, children consume more than one-third of their total energy intake whilst at school(1), thus making the content of school lunchboxes an important target for nutrition promotion efforts. Supermarkets invest heavily in promoting food for inclusion in school lunchboxes, particularly in the ‘Back to School’ period, but little is known about the nutrition content or the packaging of the foods included in these promotions. This study aimed to examine the types and packaging of foods that are promoted by supermarkets as school lunchbox foods. Catalogues for six supermarket chains in Adelaide, South Australia were collected during the four weeks of January 2023, the window often described as the ‘Back to School’ period. An audit of the contents was conducted and items promoted specifically as ‘Back to School’ items were coded according to the type of food (fruits, vegetables, dairy, grains/cereals, protein or drinks), whether the items was packaged or unpackaged and the processing classification according to the NOVA criteria(2). Descriptive statistics were calculated. In the ‘Back to School’ period, each of the six supermarket chains produced 4 catalogues and items relating specifically to foods promoted for inclusion in school lunchboxes appeared in 18 of the 24 catalogues. A total of 151 food or drink items appeared in the ‘Back to School’ promotions in these catalogues, and 100% of these items were packaged; 29% were packaged in single-use plastic packaging, 25% were packaged in recyclable packaging and 46% were packaged in a combination of single-use plastic and recyclable packaging. In terms of foods, snack foods, including sweet (n = 32, 21%) and savoury (n = 21, 14%) snacks were highly represented (35% overall). Dairy products (n = 23, 15%), grains/cereal products (n = 23, 15%) and drinks (n = 20, 13%) were also featured, and spreads (e.g. vegemite, Nutella) appeared in 13% of catalogues (n = 12). Fruits (n = 8, 5%), vegetables (n = 3, 2%) and proteins (n = 5, 3%) did not appear in many catalogues. Seventeen (11%) foods were unprocessed, with 111 (74%) classified as ultra-processed foods. Supermarket catalogues promote ‘Back to School’ lunchbox foods that are overwhelmingly packaged and ultra-processed. Working with supermarkets to adapt the promotion of foods that are less packaged and less processed is an important step to improving the local food environment.