A Fixed Rate Tariff is where the wholesale price of your gas and electricity remains the same during the length of your contract. This means that the unit rates and standing charges of your packages do not change during the contract period. If you overuse your gas and electricity allowance during your contract you will still have to cover the excess cost of the energy that you consume. Any overcharges will adhere to the fixed unit rate in your contract. For example, for each kilowatt of energy you overconsume, you will be charged the same unit rate per each kilowatt of energy you use that falls within your allowance.
Unit rate: The unit rate is the price you pay for each unit of electricity consumed and for a fixed term tariff, you will be charged the same unit rate, even if you overuse.
Standing charge: The standing charge is a daily fee to cover the costs of supplying the energy to be able to reach your property. The standing change price stays the same during your contract, regardless of how much energy you consume. The standing charge is set by the energy suppliers and reviewed quarterly by Ofgem (The Office of Gas and Electricity Markets) who regulate standing charges to ensure fairness between the supplier and consumer.