How to read your electricity bill (without losing your mind)

If you've ever opened your electricity bill and closed it again ten seconds later, you're not the problem: electricity bills in Spain are designed to comply with regulations, not to be understood by you. The good news is that, once you know where to look, they take a couple of minutes to read. Let's get to it.

The four areas that matter

Almost every bill, whichever retailer you're with, is laid out the same way:

1. Contract details: account holder, supply address, CUPS and access tariff.
2. Summary of the amount: what you're paying this month, itemised.
3. Consumption breakdown: how much energy you've used and when.
4. Regulated information: charts, comparisons and small print.

To work out whether you're paying a fair price, the first two are the ones you care about.

First of all: the billing period

Before you look at a single euro, check how many days the bill covers. It shows up as "billing period" or as two dates.

It's the figure that misleads most and the one nobody looks at. A 28-day bill and a 35-day one can't be compared with each other: the power term is charged per day, so the second one carries 25% more in fixed costs purely because of the calendar. If your electricity "has gone up" this month, the first thing to rule out is that it's simply more days.

With that settled, the comparison that does work is euros per day or euros per year, never euros per bill.

The CUPS: your home's number plate

The CUPS is a code of 20 or 22 characters starting with ES. It identifies your supply point, not your company: even if you switch retailer, the CUPS stays the same. You'll need it for any kind of paperwork, so it's worth knowing where it is — we cover the whole thing in what the CUPS is and where to find it.

Next to it you'll also see your access tariff: 2.0TD in practically any home, 3.0TD from 15 kW upwards. It isn't the tariff you signed up to with your company, but the regulated classification that decides how what you pay is structured; the difference between the two is in 2.0TD vs 3.0TD.

Power term: you pay for having it, not for using it

Contracted power (measured in kilowatts, kW) is the "width of the pipe" of your installation: how many appliances you can run at the same time. You pay for it every single day, whether you use electricity or not. You can go away for a month with everything switched off and that line is charged all the same.

It usually appears on the bill twice, because with 2.0TD you contract two power levels: one for peak and standard hours (from 8:00 to 24:00 on working days) and another for off-peak. The expensive one is the first.

This is where one of the most common overcharges hides: plenty of homes have more power contracted than they need, often inherited from the developer. If your main breaker never trips, chances are you can lower it and save without changing a single habit — we explain how in how to lower your contracted power.

Energy term: what you actually consume

This is the variable part: the kilowatt hours (kWh) you've used, multiplied by the price of your tariff. Three things to check:

• The price per kWh. This is the key figure for comparing offers. Look for it in the breakdown, not in the summary.
• The time bands. With 2.0TD, energy has three price bands (peak, standard and off-peak). If your tariff varies by time of day, shifting consumption to off-peak — the small hours and the whole weekend — makes a difference. The exact hours are in electricity prices by time of day.
• Whether the consumption is actual or estimated. Look for the word "estimated" next to the reading. An estimated bill isn't an error, but it gets trued up afterwards: if a very high one lands out of nowhere, check whether the previous one was estimated.

Watch out for the price your company advertises

This is the most common trap when comparing. Almost every offer advertises the energy price without taxes, and your bill includes them: the electricity tax and VAT (or IGIC in the Canary Islands, or IPSI in Ceuta and Melilla).

Comparing a price with taxes against one without inflates the difference by around 25%. Before you decide anything, make sure you're comparing both figures in the same unit.

Network tolls, system charges and taxes

Part of your bill has nothing to do with your company: the network tolls (for transporting and distributing the energy) and the system charges are set by regulation, and they're the same for everyone. On top of that come the electricity tax and VAT.

In practical terms: the difference between paying too much and paying a fair price is almost always in the energy price, the contracted power and the extra services — not in the tolls.

Meter rental (and why it almost never matters)

You'll also see a small line for metering equipment rental: a few cents a day for the meter, which belongs to the distribution company. It's a regulated amount and it's identical across all retailers, so it isn't a lever for saving — but it's worth knowing what it is so you don't mistake it for an extra service.

Additional services: check what you're paying for

Maintenance plans, insurance, breakdown cover… They sometimes get added when you sign up and then stay there forever. Go through the breakdown: if there are services you don't remember asking for or never use, that's money walking out the door every month. Unlike meter rental, these are optional and can be cancelled.

A word of warning: cancelling one of these services is not the same as changing tariff or changing company. They're two separate things, and the second one doesn't drag the first along with it.

The two companies that appear on your bill

It confuses a lot of people, and understanding it saves you calling the wrong place:

• The retailer sells you the energy and issues your bill. You choose it.
• The distribution company owns the cables and the meter, is assigned to you by area and can't be chosen. It's who you have to call if there's an outage, even though somebody else sends the bill.

Both usually appear, with different phone numbers. The faults number is the distributor's, and it's free.

What to check, in order, if you think you're paying too much

A five-minute list with the bill in front of you:

1. The days billed. Is it comparable with the last one?
2. The contracted power. Does your main breaker ever trip? If it doesn't, you've probably got more than you need.
3. The price per kWh, with taxes. That's your figure for comparing.
4. The split across time bands. Is your consumption off-peak or at peak? That decides which kind of tariff suits you.
5. The extra services. Is there one you don't use?

If you can answer all five, you already know more about your bill than most people — and you have exactly the data you need to compare.

And if something doesn't add up, you can complain

If you spot an error — an impossible reading, a service you never signed up to, a power level that isn't yours — the first step is to complain in writing to your retailer and keep the acknowledgement of receipt. If there's no answer within a reasonable time, or it doesn't convince you, you can take it to the consumer affairs office of your autonomous community. Always keep your bills: they're the evidence.

The quick way to find out if you're paying too much

You can do all of this by hand: note down your price per kWh, your contracted power and your extra services, and compare them with what's on the market. Or you can let technology do it: with luzgasia you upload your bill, our AI reads it in seconds, and we tell you how much you could save and why, in plain language.

And if your current tariff is already a good one, we'll tell you so. A comparison tool that always finds savings is no use to anyone.

It's free, with no strings attached and no sales calls: you see your analysis first and decide afterwards. Analyse your bill now and settle the question today.