Top up codes usually have 20 digits, however you will receive a 40 or 60 digit top up code when you top up after electricity prices have changed. This will credit your keypad meter with your top up amount and update your meter with the new unit rates. At other times you may receive a special 40 or 60 digit top up code if we have to update your Keypad meter. If you have received a longer top up code, simply key it into your meter as normal. Did this answer your question? Yes No Thank you for your feedback