This is a comprehensive data set on intra- and interspecific latitudinal variation in thermal traits in a clade of small ectotherms from Eastern Australia (genera Carlia and Lygisaurus). It includes data on metabolic rate, water loss rate, preferred body temperature, thermoregulatory precision, critical thermal minimum and maximum temperatures and performance at different temperatures in individuals of 13 different species with different latitudinal range position and range extent. For wide ranging species, several populations from different latitudes are included. The data set also includes calibration data on the lag of body temperature behind air temperature in experiments on critical thermal limits and information on the phylogeny of the study species, based on a previously published phylogeny (Pyron et al. 2013, see data set for full reference). The data was collected at James Cook University, Cairns QLD, Australia, as part of a PhD project from 2012 to 2014. Animals were collected along the Australian East Coast from locations between Canberra and Lockhart River. Detailed methodologies can be found in the related PhD thesis and publication.