These data files contain the results of Evolved Gas Analysis (EGA) on a Mettler-Toledo TGA-DSC 3+ attached to a Pfeiffer Vacuum GSD 320 gas mass spectrometer on ash samples from the 15 January 2022 eruption of Hunga volcano, Tonga. Samples were heated in Nitrogen at a rate of 5 °C/min from 30 to 150 °C for dehydration purposes and then at a rate of 30 °C/min from 150 °C to 1300 °C. During heating, the relative amount of different volatile species (H2O, CO2, SO2, HCl, and H2S, which are extracted from mass-to-charge ratios of 18, 44, 64, 36, and 34, respectively) were recorded by the gas mass spectrometer. Natural samples collected for the analysis were bulk ash material or correspond to a given ash fraction. Particles were unwashed and dried at 40°C before analysis. We compared the signals for natural samples with (i) a mixture of salt-free dense glassy particles, white and dark pumice (HT10), (ii) pure halite, anhydrite, gypsum, calcite and pyrit, (iii) mix between pure magmatic particles (HT10) from (i) and manually added components from (iii).