You open a supplier’s website: the first screen promises a discount, further down it offers to put electricity and gas on one contract, add direct debit and throw in some other service for the home. Next to all that is a price per kilowatt-hour — and it still tells you nothing about what the bill will actually be.
This is a follow-up to “Utility Bills in Portugal: What You Are Paying For, and Why the Bill Suddenly Doubles“, where we took the bill apart and explained where unexpected charges come from
To find the offer that suits you, you have to compare more than the price of energy: the fixed charge, the contracted power, the time of day you use electricity and the conditions attached to every discount.
What you actually get to choose
In Portugal the companies that sell you electricity and natural gas are separate from the companies that run the networks. You choose who to sign a supply contract with, but the electricity and gas networks themselves stay the same when you switch.
Water works differently: the local operator both runs the infrastructure and supplies the water, so there is no other company to move to.
For electricity and natural gas there are two markets in Portugal: the free market and the regulated one. They are not split by area — a customer who qualifies for the regulated tariff chooses for themselves between it and the offers on the free market. On the free market the company sets its own terms. On the regulated market the price of energy is set by ERSE, Portugal’s energy regulator, and the contract is with a supplier of last resort, the comercializador de último recurso, or CUR. The regulated tariff is currently provided for until the end of 2027; for electricity it is open to household customers on standard low-voltage power, and for natural gas to customers using up to roughly 10,000 cubic metres a year.
The regulated tariff is not automatically cheaper. It is simply one more offer to compare against. An electricity bill on the free market has to show the difference between what you paid and what you would have paid on the regulated tariff. If that line keeps telling you the regulated option would have cost less, it is worth checking it in the simulator.
A fidelização period is not part of every contract. A supplier can only tie you to a minimum term in exchange for something concrete — a discount or an extra service, say — and for no more than about a year. There is no standard exit fee: the amount, or the formula used to calculate it, has to be stated in the contract. So before you switch, check first whether you are inside a fidelização period and what leaving early would cost.
How to compare offers
Take the figures off your last bill
To compare offers, use a bill for an ordinary month — no long absence, no correction for earlier periods, no unusual winter consumption.
What you need from it:
- the address or postcode;
- the service: electricity, gas or both;
- potência contratada — the contracted power for electricity;
- the metering option: simples, bi-horária or tri-horária;
- consumption in kilowatt-hours, ideally over a full year;
- for gas, the escalão de consumo — your annual consumption band;
- the name of your current tariff and any discounts attached to it
If you have no annual figure, you can work from the last few bills, but the seasons will skew the result. A flat with electric heating is effectively two different customers in winter and in summer.
Put your figures into the ERSE simulator
The official ERSE simulator compares free-market offers and the regulated tariff side by side. It is more useful than individual companies’ websites: instead of one attractive rate it shows the calculated total for your own consumption profile.
Enter your own figures from the bill rather than picking a ready-made example household. Annual consumption, contracted power and the metering option matter most. Put in a lower power or a lower consumption than you really have and the simulator will price a bill that is not yours: at your actual usage the totals come out differently, and the offer at the top of the list may no longer be the cheapest.
Sort the results by expected annual cost. A monthly discount or a welcome gift can make the first bills look better without making the contract itself cheaper. Open several of the top offers, not just the first one: a small difference in the calculation can come with very different terms.
Why the price per kilowatt-hour is not enough
With electricity you pay for at least two commercial elements: the energy you used and the power available to you. So a tariff with cheap energy but a high daily charge for power can work out badly for a flat where one person lives, there is no electric heating, water heater or air conditioning, and consumption is low.
Gas follows the same logic: there is a variable part for what you use and a fixed part. The less gas you use, the more the standing charges show up in the final total.
Part of the bill has nothing to do with your supplier at all. Network access charges are set by ERSE and included by every company. So a promise that “electricity is cheaper here” does not mean the whole bill — taxes, network charges and levies included — falls by the same amount.
Check your power against what you actually run
Potência contratada determines how many appliances you can run at once. The higher it is, the higher the fixed part of the bill. Set too high, you overpay every month regardless of consumption. Set too low, the power cuts out when the oven, the water heater and a heater are all on together.
ERSE has a separate power simulator. It asks which appliances need to work at the same time and helps you judge the right level. Don’t lower the power in the simulator just to get a smaller figure: check first that it covers the appliances you normally have running together.
How the tariffs differ
A flat rate or electricity priced by the hour
As we wrote in the previous piece, a time-of-use tariff pays off only if you can genuinely move a noticeable share of your consumption into the cheaper hours: heating water, washing, drying, the dishwasher or charging a car.
If people are at home working during the day, cooking in the evening and have no wish to arrange their lives around a schedule, the flat rate is often the more straightforward option. The honest way to check is smart-meter data, or at least a candid look at your own habits.
A fixed price or an indexed one
On a fixed-price contract the supplier sets the cost of energy in advance for a defined period. Under the new rules, large suppliers have to offer an option with a fixed price and a fixed term of at least a year. That does not mean the whole bill stays the same: consumption, taxes and the regulated network components can all change. So when you compare, ask specifically for the one-year fixed offer and set it against an indexed one.
An indexed tariff tracks the wholesale market. In calm periods it can work out cheaper, but a month when the market jumps shows up in the bill straight away. It suits people who are willing to watch prices and switch again if they need to. If what matters most is a predictable household budget, a small calculated saving may not be worth the risk.
One contract for electricity and gas is not always cheaper
Dual means a single contract covering electricity and natural gas. It is easier to pay, and the company may add a discount for taking both. But a discount on the bundle is not proof that it is cheaper: the best standalone electricity tariff plus the best standalone gas tariff can add up to less.
Run three calculations in the simulator: both services together, electricity alone and gas alone. Compare the annual totals. If the difference is small, then it is a question of how much you value one bill and one customer-service line.
Where the overpayment usually hides
Overpaying usually comes not from the headline rate but from the conditions around it: a discount can run out quickly, depend on how you pay, or require a service you don’t need.
- A discount that only covers the first months. Check straight away what the price becomes once the promotion ends
- A discount conditional on débito direto or fatura eletrónica. Turn off direct debit or electronic billing and the terms change
- Insurance, call-out cover or equipment servicing. These services are not required in order to be supplied with energy. The company has to offer a contract without them
- A fidelização period. Check whether the contract ties you to a minimum term, and what amount or formula it gives for leaving early
- A price with no clear period of validity. Check when the supplier is entitled to change it and how it has to notify you
Before you sign, ask for the ficha contratual — the standard summary of the contract. It should bring together the price, the metering option, the payment method, the billing period, any extra services and whether there is a minimum term. That is easier than hunting for each condition across dozens of pages.
How to switch supplier
You normally don’t have to cancel the old contract yourself: the new supplier arranges the switch. ERSE states that switching is free, must not interrupt your supply and has to be completed within about three weeks. Before you move, check whether the old contract still has a fidelização period running: leaving early can carry the charge set out in it. Under the new rules your electricity also cannot be cut off while the supplier is examining a formal complaint about a disputed bill.
To sign up you usually need an identity document, your NIF, bank details if you are paying by direct debit, and the identifier of your connection point: CPE for electricity, CUI for gas. Both numbers are on your old bill. If you have the social tariff for electricity, the new rules say it carries over automatically when you switch — there is no need to apply again.
On the day of the switch, photograph the meters and submit the readings. The old supplier has to send a final bill within about six weeks. The photograph is what lets you check that part of your consumption has not been billed twice or estimated.
Choosing in ten minutes: the short version
- Take a bill for an ordinary month and find your annual consumption, your contracted power and your metering option.
- Check the comparison with the regulated tariff printed on the bill.
- Run the ERSE simulator with your own figures.
- Open several of the best results and compare the expected annual total with all discounts included, not the size of the promotion.
- Strip out insurance and services you don’t need.
- Check how long the discount lasts, the direct-debit conditions and the fidelização period.
- For electricity, check your contracted power separately, and whether a tariff with different prices at different times of day suits you.
- Before you agree, ask for the ficha contratual and keep it with the contract.
The cheapest supplier for your neighbour is not necessarily the cheapest for you. In a flat with low consumption the fixed part matters most; in a house with electric heating it is the price of energy; on a two-rate meter it is the hours in which that energy is used. So what you are choosing is not a company “with good tariffs” but one specific offer measured against your own bill.
