Start by checking the bill covers the correct address, billing period and meter readings, then compare the readings with your meter to spot possible errors. Review your unit rates, standing charge, payment method and any outstanding balance, and contact your supplier if something does not look right. Ask whether a cheaper tariff, smart meter or different payment arrangement is available, but check exit fees and terms before switching. If you are struggling to pay, contact your supplier promptly to discuss support and check the latest help on GOV.UK, as eligibility depends on your circumstances.