There is no time limit to this tariff, leaving you free to switch at anytime without an early exit fees. Customers coming to the end of an npower fixed term and fixed price tariff will automatically be moved to this Standard tariff unless they have actively switched to another tariff.Standing and Other Charges: This tariff has a. This applies, no matter how much energy you use.eâve put a brief summary below for you, but please ensure you download and read all the terms and conditions: Download Standard terms and conditions (PDF, 441KB). To see an estimate of how much youâd be paying with our Standard variable tariff, get a quote.