We offer a wide selection of propane tanks for your home and business. Our above-ground tanks come in 120, 250, 500, and 1000-gallon volumes. We also offer underground tanks in 250, 500 and 1000-gallon volumes. Choosing the right tank size can save you money by controlling how often your tank needs to be filled. Review the propane tank size guide below for more information on propane tank sizes. Tanks are filled to a maximum of 80% of their capacity. As the temperature changes, the liquid propane in the tank expands.