9d049bb1_Bill___Help___Support___npower__Monthly_Direct_Debit
[0] Payment frequency Quarterly - your payment will be taken from your bank account 19 calendar days after your invoice is produced, or on your preferred payment date. If your preferred payment date is within 19 days of your invoice date, payment will be taken on your preferred day the following month. [Receipt of Bill] Quarterly - you'll have 14 calendar days from the date on your bill to pay for your energy. [Monthly Direct Debit] 
Monthly - choose a payment day to suit you.
Paying Your Energy Bill | Help & Support | npower
Monthly Direct Debit