The datasets represent the observed abundance of macrofauna (retained on a 0.5mm mesh sieve) retrieved from 24 subtropical mudflats along the south-east coast of Australia in 25cm x 25cm box cores and 50cm x 50cm quadrats (to a sediment depth of 11cm). Sites were located between south Deception Bay and Tallebudgera, Gold Coast. Sampling was carried out in winter 2016 (July-August) and summer 2017 (January-February). The summer assemblages contained more species, more individuals and had differing taxonomic composition. The 24 sites were categorised into four land-use sub-catchments e.g. high industry, low industry, residential and peri-urban (see paper for categories and site classifications).