Shiga toxigenic Escherichia coli (STEC) are an important cause of bacterial enteric infections, which usually cause acute and often bloody diarrhoea, and can also be responsible for a wide spectrum of disease ranging from mild non-bloody diarrhoea to haemorrhagic colitis (HC) and haemolytic uraemic syndrome (HUS). A number of rapid immunoassays for the detection of Shiga toxin in faecal specimens are available on the market, including the SHIGA TOXIN QUIK CHEK (Techlab®, Blacksburg, VA, USA) which can be tested on direct faecal specimens and the ImmunoCard STAT! EHEC which can be tested on enriched faeces cultures. This study evaluated both assays for their ability to detect all known subtypes of Shiga toxin and evaluated for clinical performance using a multiplex PCR for Shiga toxin target genes as the gold standard. Impressively, the SHIGA TOXIN QUIK CHEK was able to detect all known Shiga toxin subtypes with the exception of Stx2f; while in contrast the ImmunoCard STAT! EHEC assay was unable to identify four of the seven Stx2 subtypes, including Stx2b and Stx2d which are associated with human disease. In comparison to the multiplex PCR, the SHIGA TOXIN QUIK CHEK and the ImmunoCard STAT! EHEC assays both gave 100% specificity, with 50.0% and 38.5% sensitivity respectively.