Energy suppliers are scrambling to avert a repeat of the meter reading chaos in March which saw websites crash as customers raced to submit readings before prices soared.
British Gas and companies have told customers they have up to a week to submit their readings, so long as they were taken before the next rate increase on October 1.
From October, the Government’s Energy Price Guarantee will take effect, limiting the average household annual bill to £2,500. Bills will still rise, but not as much as they would have had the Government not intervened.
Households who do not have smart meters are required to submit meter readings so that their provider can adjust their bill based on actual usage rather than estimates.
As of October 1, the unit price for electricity will rise by 20pc, while the price of gas will rise by 40pc.
Those who have smart meters do not have to submit readings, as this is done automatically. In March, providers’ websites buckled under the strain of thousands of customers trying to submit readings at the last minute.
Companies blamed Money Saving Expert founder Martin Lewis for encouraging households to submit readings the day before the price cap increase.
Customers supplied by Octopus Energy have a week to submit their readings, provided they were taken on October 1, while E.ON customers have five days.
British Gas has set a deadline of October 14, assuring customers there was “no rush”, and Shell Energy has offered households a window of up to 30 days.
Bulb assured customers they would be allowed to backdate a reading if they could not submit one in time.
A spokesman said: “The easiest way for customers to submit a reading is via the Bulb app or on their Bulb Account.
“Customers don’t need to worry if they can’t submit a reading during this time period. If they need to backdate a meter reading, they can email the reading and the date it was taken.
“And if customers have submitted a meter reading in September, we’ll be able to produce extremely accurate estimates for the final days of the month.”
Submitting a reading today would ensure that energy companies have an accurate picture of households' usage before the higher rates come in, Gillian Cooper of Citizens Advice said. It will also make it easier for customers to contest bills they think are wrong.
Comparison website Uswitch has advised customers to leave it as late in the day as possible before they send a reading to ensure that as much of their energy use as possible is calculated under the old rates.