Australian supermarket volumes are likely to drop by 2% in FY24e on a per capita basis, which is a continuation of declines seen since March 2022. While higher food prices may explain some of the softness in volumes, other factors are at play including channel leakage, lack of store refurbishments and less new product innovation. We forecast 3.0% comparable sales growth for the supermarket sector in FY25e, but a downside case of 2.3% is possible if volumes continue to decline. A low rate of comp sales growth would be very challenging given comp cost growth is unlikely to fade. Weaker comp sales will put downward pressure on Coles and Woolworths profit margins.