If the meter reading window is still open (within 21 days from the Move date), you can provide an up to date meter reading to the new energy supplier.

If the meter reading window has closed (i.e. it has passed the 21 day window from the Move date), you'll need to provide the last meter reading and the most recent meter reading to both the previous and new energy supplier. Depending on the date of the readings, the new bill issued may still be considered an estimate, but the amount payable would be much more accurate.