CNMC comparator
The CNMC comparator is the official reference for checking market offers. It asks for details such as postcode, contracted power, estimated annual consumption and tariff type.
Visit CNMC comparatorElectricity comparison in Spain
CNMC vs Si Compare vs UswitchSpain
A list of electricity tariffs is useful, but it is not the same as a recommendation. In Spain, the best deal depends on the bill, the contracted power and when the home uses electricity.
Why your bill matters more than the advertised kWh price
Real usage
A recent bill shows actual consumption, contracted power and the structure of the current contract.
P1, P2 and P3
Two homes with the same annual kWh can need different tariffs if one uses power at night and the other uses it in peak hours.
Contract details
Fixed charges, potencia, services, permanence and solar/EV features can change the real annual cost.
Online comparison sites
Sites such as Si Compare are convenient for quick online quotes and switching. The important question for any comparison site is whether the result is based on a broad tariff calculation or a simpler lead-generation flow.
UswitchSpain bill analysis
We start with the bill because usage pattern drives the recommendation. Where available, we look at the full-year picture, P1/P2/P3 split, fixed charges and supplier-specific tariff structure.
Comparison methods at a glance
| What matters | CNMC | Typical comparison site | UswitchSpain |
|---|---|---|---|
| Official supplier offer database | Yes | Usually selected partners | Market tariff database plus bill analysis |
| Starts from your actual bill | Manual inputs or bill-derived data | Usually postcode and usage details | Yes, bill upload is the starting point |
| Looks beyond headline kWh price | Shows comparable offer costs | Varies by provider | Yes, fixed charges, potencia, extras and taxes |
| P1 / P2 / P3 usage pattern | Uses tariff-period settings and consumption inputs | Often simplified | Core part of the recommendation |
| Full-year usage context | Depends on what the user enters | Often recent bill or estimate | Used when available to avoid seasonal mistakes |
| Advisor checks the recommendation | No managed advice | Sales or switching support | Yes, analysis plus human review |
The key difference: we do not start with a supplier
Gana Energía, Octopus, Endesa, Iberdrola, Naturgy and Repsol can all be the right answer for a specific home. They can also be the wrong answer for another home with a different pattern.
That is why UswitchSpain ranks tariffs by fit for the client's usage profile. A low headline rate is not enough if the fixed charges, period split or contract structure make the total bill higher.
Want the comparison that fits your home?
Upload your bill and we will check the tariff against how your home actually uses electricity.
Upload my billFAQ
Is the CNMC electricity comparator the best way to choose a tariff?
The CNMC comparator is one of the best official references for checking available electricity and gas offers in Spain. It is useful for market transparency, but it is not the same as an advisor reviewing your bill, your P1/P2/P3 usage pattern, your fixed charges and whether the tariff really fits your home.
Why does UswitchSpain need a bill upload?
Because a Spanish electricity tariff cannot be judged properly from the supplier name or headline kWh price alone. Your bill shows contracted power, current tariff structure, usage, taxes, fixed charges and sometimes period consumption. That lets us compare the real total cost instead of guessing.
Why do P1, P2 and P3 periods matter so much?
P1, P2 and P3 are the peak, mid-price and off-peak electricity periods used in many Spanish tariff structures. Two homes can use the same annual kWh but pay very different amounts if one uses most electricity at night and the other uses it during peak hours. That is why period split can change the best tariff recommendation.
Can one month's bill really show the best electricity tariff?
One bill is a useful starting point, but it can be misleading for seasonal homes, pool pumps, air conditioning, electric heating, EV charging or solar owners. Where available, a full-year view is stronger because it captures summer, winter and shoulder-season behaviour.
Is UswitchSpain an alternative to Si Compare?
Yes, if you want a bill-led electricity comparison rather than a simple quote journey. Online comparison sites can be convenient, but the important question is whether the recommendation is calculated from your actual usage and contract structure, not just from a small number of input fields.
Is there one cheapest electricity supplier in Spain?
No. A supplier that is cheap for one home can be expensive for another. The right recommendation depends on the customer's usage profile, not the supplier name alone.
Why are Gana Energía tariffs not always at the top?
Gana Energía can be competitive for some customers, but no supplier wins every usage profile. We rank tariffs by estimated fit for the bill we are analysing, so Gana, Octopus, Endesa, Iberdrola, Naturgy or another supplier can move up or down depending on the home.