Iberdrola vs Endesa: how Spain's two giants compare in 2026

If you've moved to Spain or bought a house here, these are the two names you'll hear first. More likely, your home already has one of them as its electricity supplier. They are the biggest retailers in Spain, and between them they supply a huge chunk of Spanish households. Their vans, adverts and door-to-door reps are everywhere. You'll even find them at your local Leroy Merlin. It's the battle of the giants: Iberdrola vs Endesa.

What kind of companies are they?

Both are old, both are huge, and both are foreign-linked at the top despite feeling very "Spanish".

Iberdrola is headquartered in Bilbao and listed on the Madrid stock exchange. The group supplies energy to close to 100 million people across the UK, US, Brazil and beyond, with roughly 11 million customers in Spain alone. It spent the last two decades building one of the world's largest renewable generation fleets, and that green identity is central to how it markets itself.

Endesa is based in Madrid, was founded back in 1944, and is now a subsidiary of the Italian group Enel. It serves around 9.6 million electricity customers in Spain and runs one of the broadest tariff catalogues on the market, from flat-rate plans to night tariffs to solar self-consumption deals.

Iberdrola vs Endesa tariffs: what's the difference?

Here's the honest headline: for a normal home, the structure of what they sell is very similar. Both offer fixed-price plans, time-of-use plans, and the regulated PVPC through their reference-supplier arms. The real differences are in the details and the packaging.

Iberdrola leans digital and streamlined. Its 2026 free-market line-up centres on a small number of plans: Plan Online (a flat all-day rate), Plan Online 3 Periodos (three time bands), and Plan Estable (a longer fixed-price lock). Fewer options, cleaner app, less to think about.

Endesa goes wide instead of narrow. Bigger catalogue, more variants, more promotions, plus specific products for solar self-consumption and electric-vehicle owners. More choice, but also more to compare and more fine print to read.

Two things are worth knowing regardless of which you pick. First, the plan name on your bill matters more than the brand: two people on "Endesa" or two people on "Iberdrola" can pay very different rates depending on the specific tariff and when they signed. Second, rates on these free-market plans get revised, and renewals can land higher than the intro price, so the number you see when you sign is not necessarily the number you pay next year. Another good reason to compare your bill every now and then.

If you're not sure which line on your bill tells you the plan and the rate, we walk through it in how to read your Spanish electricity bill.

Are they green?

This is where the two genuinely are different.

Iberdrola markets all of its major free-market tariffs with 100% renewable electricity certified by Guarantees of Origin (garantías de origen). It also owns one of the largest renewable generation portfolios in the world, so the green claim is backed by actual wind, hydro and solar assets, not only certificates.

Endesa (via parent Enel and Enel Green Power) has a large renewable fleet too, and offers green-certified tariffs. The catch: not every Endesa tariff is sold as 100% renewable by default. If green sourcing matters to you, you have to check the specific plan rather than assume it.

A note on what "green" really means here. In Spain, a "100% renewable" retail tariff almost always rests on Guarantees of Origin, a certificate system. Certified electricity is a real and standard thing, but it isn't the same as saying every electron in your socket came from a wind farm or a solar field. Both companies play by the same certificate rules. Iberdrola simply applies the badge across more of its range by default.

Why might you choose Iberdrola?

• You want green sourcing without having to hunt for it. The renewable badge is on the flagship plans by default.
• You prefer a simple, digital experience. Fewer plans, a well-rated app, easy online management.
• You like the idea of a fixed rate you can hold for a longer stretch (Plan Estable).
• Its Trustpilot rating sits a little higher than Endesa's, at around 4.2/5 across roughly 14,000 reviews at the time of writing.

Why might you choose Endesa?

• You want to walk into a physical office and speak to someone. Endesa has branches across Spain, which some expats value over app-only support.
• You have a specific setup (solar panels, an EV, an unusual consumption pattern) and want a plan tailored to it. The wide catalogue helps here.
• You're chasing a particular promotion or bundle. Endesa runs a lot of them.
• Endesa sits around 3.8/5 on Trustpilot across roughly 12,000 reviews, lower than Iberdrola but still in "average for a big utility" territory.

What are the Iberdrola and Endesa apps like?

Both companies push you toward self-service, so the app is where you'll actually live: checking bills, tracking usage, and trying to sort out problems without queuing on a Spanish-language phone line. Here's how the two compare.

Ratings are from Apple's App Store and vary by country store; the figures above are the Dutch store as of August 2026.

Beyond the star average, the reviews tell a more useful story:

• Iberdrola's app is the more capable one, but Spanish-only. It does genuinely more: change your contracted power in-app, monitor solar generation in real time, break your consumption down by appliance, and report a fault without phoning. The catch for expats is that there's no English. Reviewers have been asking for English support for years, and it still isn't there.
• Endesa lists English, but users say it doesn't work. On paper the app offers English and Catalan. In practice, reviewers report that switching to English changes nothing and the app stays in Spanish. Don't count on it until you've tested it yourself.
• Endesa's app carries ads and has a much smaller review base (~140 vs ~1,200), so its average is less settled. Several reviews report it simply not working for them.
• The recurring expat horror story is about leaving, not the app. One reviewer described paying off and cancelling their contract before moving abroad, getting no reply for months, then being chased by a debt-collection intermediary. That's an account-closure and customer-service failure, and it's exactly the kind of friction that shows up with big incumbents.

The honest takeaway: neither app will reliably hold your hand in English. If in-app English matters to you, test it before you commit, and remember that some smaller suppliers do better on this than the giants. One of the best apps we've tested belongs to Frank Energy.

What do regulators say about Iberdrola and Endesa?

Star ratings tell you how people feel. Spain's regulator, the CNMC, tells you what actually happened. Here's the picture from official data, which is far harder to spin than a review page.

A few things worth pulling out:

• Both giants are slowly bleeding customers. Independent retailers grew from 8% of the free market in 2019 to 22% in 2025. People are leaving the big names for smaller ones, which is the trend this whole comparison sits inside.
• The 2025 blackout follow-up is live. After the 28 April 2025 national blackout, the CNMC opened 20 sanctioning cases against generators, 12 of them split between Endesa and Iberdrola, all classed as "serious". The regulator has until October 2027 to resolve them, so this is unfinished business, not a closed chapter.
• Customer service is a sector-wide weak spot, not one company's flaw. A CNMC "mystery shopper" study across retailers covering 97% of the domestic market found persistent problems: unclear pre-contract information, hard-to-process cancellations and long phone waits. Late in 2025 the CNMC opened files against both Iberdrola and Endesa (among others) over complaint-handling. Treat glowing or damning reviews of either with a pinch of salt.

One more thing that matters if you get a cold call: since February 2026, retailers are banned from pitching contracts by phone unless you asked them to first. Iberdrola and Endesa both backed that ban. If either "calls to offer you a better rate" out of the blue, that's a red flag, not an opportunity.

The honest bottom line

Neither is clearly "better". They're two large incumbents with similar core products and different personalities: Iberdrola is greener-by-default and more digital; Endesa is broader and more bricks-and-mortar. Customer reviews for both split hard between people who never have a problem and people stuck in a billing or call-centre loop, which is typical for utilities this size.

What actually determines your bill is the specific plan and your own consumption pattern, not the logo. Big incumbents rarely offer the cheapest per-kWh rates on the market, so it's worth checking your current bill against smaller retailers before assuming either giant is your best option. That's the thing worth spending five minutes on.

If you want to see how the giants stack up against the newer names, we've done another head-to-head: Iberdrola vs Octopus Energy. For the practical side, see how to switch supplier in Spain and how to lower your electricity bill in Spain. Worth reading alongside: why your potencia contratada is probably wrong, dynamic (indexed) contracts explained and solar panels in Spain.

FAQ

Is Iberdrola or Endesa cheaper? There's no single answer. It depends entirely on which tariff you're on and how much you use. Two households with the same supplier can pay very different rates. Compare the specific plan, not the brand name.

Are both Iberdrola and Endesa 100% renewable? Iberdrola markets all its major free-market tariffs as 100% renewable via Guarantees of Origin. Endesa offers green-certified tariffs but not every plan is renewable by default, so check the specific one.

Do the Iberdrola and Endesa apps work in English? Not reliably. Iberdrola's app is Spanish-only, and reviewers have requested English for years without result. Endesa's app lists English and Catalan, but users report the English setting doesn't actually change the language. If you need in-app English, test it before committing.

Can I switch between them for free? Yes. Switching electricity supplier in Spain is free, there's no supply interruption, and the new supplier handles the paperwork. It usually takes a couple of weeks. Watch out for permanence clauses on add-on services such as maintenance insurance, which can carry their own commitment.

Do they support English-speaking customers? Both offer some English support, but quality is inconsistent, especially by phone, which is a common complaint from expats with both companies. Endesa's physical offices can help if you prefer talking to someone in person.

Is PVPC available from both? Yes, both offer the regulated PVPC tariff through their reference-supplier arms. PVPC is also the only route to the bono social, the means-tested discount, if you qualify.

What can I do if Iberdrola or Endesa won't resolve my complaint? Escalate. In 2024, of the 968,000 people who complained to their electricity company, only 38% got a favourable result in first instance. When customers took it to a Junta Arbitral de Consumo (a free, out-of-court arbitration body), the success rate jumped to nearly 80%. Fewer than 2% of consumers use it, mostly because almost nobody knows it exists. It applies to any retailer, big or small.

Does HolaSwitch recommend Iberdrola or Endesa? No. We don't partner with either and earn nothing if you sign with them. We include them for comparison because they're the market's biggest names, but our comparison flow focuses on retailers we can actually assess against your bill.

Sources

• Iberdrola España company profile: https://www.iberdrola.com/about-us/iberdrola-espana
• Iberdrola electricity products (renewable claim): https://www.iberdrola.com/about-us/products-services/electricity
• Endesa company profile (Enel subsidiary, customer numbers): https://finance.yahoo.com/quote/ELEZF
• Iberdrola Trustpilot: https://www.trustpilot.com/review/iberdrola.es
• Endesa Trustpilot: https://www.trustpilot.com/review/www.endesa.com
• Iberdrola Clientes app (App Store): https://apps.apple.com/nl/app/iberdrola-clientes/id883078092
• Endesa Clientes app (App Store): https://apps.apple.com/nl/app/endesa-clientes-luz-y-gas/id602095382
• CNMC retail market report 2024: https://www.cnmc.es/prensa/inf-minorista-electricidad-gas-24-20250804
• CNMC customer-service mystery-shopper findings: https://portal-cec.consumo.gob.es/en/comunicacion/noticias/2025/cnmc-identifies-deficiencies-customer-service-electricity-and-gas
• CNMC complaints and arbitration success rates: https://www.cnmc.es/prensa/reclamaciones-consumidores-energia-20260428