Check whether the bill is based on an actual meter reading or an estimate, and compare the usage with the same period last year. Gas bills can also include fixed daily supply charges, seasonal heating, changes in tariffs, or a longer billing period. Look for any outstanding balance, late fees or adjustment, then contact your retailer if the usage seems wrong or you suspect a meter issue. Your retailer can explain the bill and arrange a meter check where appropriate; avoid using gas appliances if you suspect a leak and contact emergency services or your distributor.