The adsorption characteristics of methane on a Maxsorb II specimen of activated carbon were measured over the temperature range of (281 to 343) K and at pressures up to 1.2 MPa using a new volumetric measurement system. The adsorbent was characterized through properties such as the skeletal density, Brunauer−Emmett−Teller (BET) surface area, and pore-size distribution. The adsorption data were fitted to two isotherm models proposed by Tóth and Dubinin−Astakhov with a predictive accuracy of better than 3 %. The present data were compared with those of various researchers with comparable specimens and found to be consistent with those in the open literature. The present data could complement efforts in designing adsorbed natural gas storage systems.