Your electricity usage cost is generally calculated by multiplying the kilowatt-hours (kWh) you use by your retailer’s usage rate, then adding fixed daily supply charges and any applicable fees. Your bill may also include different rates for peak, off-peak or controlled-load electricity, depending on your tariff and meter. Compare the meter readings, billing dates and rates on your bill, and check whether the reading was estimated rather than actual. For help understanding a charge or changing plans, contact your electricity retailer or use the Energy Made Easy comparison service.