Why September's bill is the highest of the year (and what to do before winter)

Back from vacation, the highest bill of the year arrives. It's not just an impression: the September bill covers consumption in July and August, the weeks when air conditioners run for hours and refrigerators work harder. Record consumption, calculated on the highest prices of the last twelve months.

The clearest public benchmark is the price set by ARERA for the Enhanced Protection service. It directly affects approximately 3 million vulnerable customers, but it also sets the direction of the wholesale market, which also governs free market offers. In January, it was 27,97 cents per kilowatt-hour; in July, it rose to 31,63: a 13 percent increase in six months, the result of two consecutive increases—up 8,1 percent in the second quarter and up 4,6 percent in the third.

Those with an indexed contract have already seen that increase on their bill. Those with a locked-in price will see it at the end of the contract, when the supplier proposes the new terms.

"September is the month when people start looking at the numbers again," says Alessandro Ferraro, co-founder of Billding, a platform that analyzes bills and protects families and businesses from price increases by monitoring contracts over time and flagging when conditions change. "For eleven months, the bill is paid and archived. The return bill, however, is read, because it's painful. And it's the right time to do a couple of checks that will then be valid for the entire winter."

There's also a scheduling reason. At the end of September, ARERA updates the conditions for the fourth quarter, covering October, November, and December: the months when the heating is turned on and the gas bill becomes more expensive. Arriving at that appointment with a contract already verified is different from being subjected to it.

Here are five checks to do before filing your return bill.

1. Look at the reference period, not the date. The first useful line isn't the amount, but the consumption range. If it covers July and August, the high amount is normal and shouldn't be compared to the May amount. A sensible comparison is with the same period last year: if the kilowatt-hours are similar but the amount has increased significantly, the problem isn't consumption but the unit price.

2. Check the price of energy. This is the item you can influence, and it's the only one that varies from supplier to supplier. Transport, system charges, and taxes are set by ARERA and are the same for everyone. Those who signed a contract three years ago and never looked at it again almost always pay a price that's out of line.

3. Check if you've received a renewal notice. In the free market, suppliers can offer new pricing terms that take effect automatically if the customer doesn't respond. Notices arrive via email or attached to the bill, and in the summer, they're often overlooked. It's worth double-checking your emails in July and August.

4. Review your contracted power. Many families pay a fixed fee for 4,5 kilowatts when they usually use 3. This is a cost that is paid year-round regardless of consumption: adjusting it to your actual needs reduces all future bills, not just this one.

5. Don't forget about gas before you need it. With the radiators turned off, the gas bill seems irrelevant, but the fixed fees for transportation, distribution, and charges continue to be charged. It's also the only time of year when you can change your gas plan without rushing: from October onward, you're under pressure.

"The problem with the Italian energy market is asymmetric information: complex contracts, automatic renewals, clauses that no one reads," adds Ferraro. "A family doesn't have the time to become an energy expert, and they shouldn't need to. Our job is to perform that check for them, and continue to do so over time."

To compare your bill: www.billding.it
For institutional comparison ARERA: portaleofferte.it

Who is Billding
Billding is the Italian digital platform for managing electricity, gas, internet, and telephone bills. Through automatic bill analysis and continuous monitoring, Billding protects families and businesses from price increases, restoring transparency and savings. It has over 20.000 users; the Billding Observatory is based on over 7.000 analyzed transactions, with an estimated average savings of €328 per year per supply point, rising to approximately €700 for small businesses. Selected by Altroconsumo as its official business comparison site, it collaborates with FIPE-Confcommercio, Satispay, and Qonto. It is rated 4,9 out of 5 on Trustpilot with over 1.100 reviews. Founded in 2022 by Alessandro Ferraro, Nicolò Sozzi, and Pinò Surace, all three of whom were included in the Forbes Under 30 Italy 2026 ranking.

Data sources: ARERA, updates to protection conditions for the first and third quarters of 2026. Billing Observatory on over 7.000 applications analyzed; the savings indicated are estimated during the analysis phase.