Sometimes you may see a negative bill or a positive bill with a negative line for gas or electricity. This happens because of system estimations. We produce bills using actual data whenever possible — from smart meters (where available) or from meter readings you’ve provided.

If no reading is available for your bill date, our system will estimate usage based on the last reading we received and the industry data held for your property. 

Occasionally, these estimates may be higher than your actual usage. When we later receive a lower actual reading, the system recalculates your account, which can result in a negative bill or a negative bill line.