ABSTRACT Necrophagous insect species are used in forensic entomology to assist with the estimation of the minimum post-mortem interval (PMImin). However, chemical substances applied to a corpse in a bid to conceal remains may affect the attractiveness of a corpse to insects and consequently the insect succession and decomposition. This study investigated the potential for two readily obtainable substances, hydrated lime and bleach to affect decomposition and associated insect succession in porcine remains outdoors and above ground during autumn, winter and spring in the Geelong region of Victoria, Australia. The substances were correlated with a significantly longer pre-appearance interval (PAI) (>12 hours) and delayed oviposition during colder months. Further, remains deposited during autumn and spring did not skeletonize when substances were present. These findings show the importance of considering the presence of bleach and hydrated lime on remains when estimating PMI.