Therms measure energy
A therm equals 100,000 British thermal units. Gas meters often measure volume, while the utility applies a heat-content factor to bill energy in therms.
Separate variable and fixed charges
Commodity gas, delivery and riders may each vary with therms. The customer charge is usually fixed. Add the variable lines to find the effective marginal price per therm.
Weather drives comparisons
Heating-degree days and thermostat settings can dominate winter use. Compare similar weather periods or normalize by daily consumption before drawing conclusions.
Editorial standard
This guide explains general billing math. Utility tariffs and local rules control your actual charges. Sources and update practices are documented in our methodology.
Read the methodology →