9d049bb1_Bill___Help___Support___npower__Monthly_Direct_Debit
[0] Your payment amount Variable depending on the energy you've used in the 3 months prior to your bill being issued. You will be required to submit meter readings to avoid estimated bills. [Receipt of Bill] Variable depending on the energy you've used in the 3 months prior to your bill being issued. [Monthly Direct Debit] 
Set at 1/12th of your annual forecasted usage. Your set monthly payment amount is reviewed during the year to ensure you're paying the right amount for what you use and you'll be advised if it needs to change.
Paying Your Energy Bill | Help & Support | npower
Monthly Direct Debit