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Electricity & gas · Spain
Checked 2026-09-30

🗓️ Estimated bills and back-billing in Spain: how far back can my supplier charge me?

The short answer

If your meter was not read for a long time, a large catch-up bill can follow. Many countries limit how far back a supplier may charge and set rules for meter readings.

📜 The rules in Spain

Back-billing and estimated bills

If your supplier billed you too little, it may correct at most one year back and you can pay the difference in as many monthly bills as months passed since the error. Overcharges must be refunded in full on the next bill, with interest (Art. 45 RD 88/2026).

  • Meters are read monthly (every two months only without remote reading). If the reader cannot access your meter, they must leave a notice; the consumption may be estimated only if you do not provide the reading within 10 working days (Art. 43). (boe.es)
  • If a supplier agrees other billing terms with you on the free market, it must still bill on actual consumption at least once a year. (boe.es)
Official source: boe.es · Checked 2026-09-30

🪜 Step by step

  1. Read your meter nowTake a dated photo and send the reading to your supplier. It stops estimates from growing.
  2. Check the period on the billWhich months are charged, and was the reading real or estimated?
  3. Compare with the rulesSee below how far back a supplier may bill in Spain and how often your meter must be read.
  4. Dispute in writingIf the bill goes back further than allowed, write to the supplier, then to the dispute body below.

📇 Who to contact

Juntas Arbitrales de Consumo / entidades de resolución alternativa acreditadasSettles disputes with energy companiesWhen the company has not solved your complaint🔗 justoparaeso.consumo.gob.es
CNMC - Comisión Nacional de los Mercados y la CompetenciaSupervises energy companies and explains your rightsFor information, and to report a company that breaks the rules🔗 www.cnmc.es

❓ Questions

Do I have to pay a huge catch-up bill at once?

Ask for a payment plan. Many suppliers must offer one; the rules for Spain are on this page.

Why did I get an estimated bill?

No reading was available. Send a real reading and ask for a corrected bill.

What if the meter was faulty?

Ask the grid operator to test it. Keep the test report for your complaint.

📎 Sources

Checked: 2026-09-30

🧭 Is this still correct?

We check this information carefully, but phone numbers, websites and rules change — and sometimes we get something wrong. Spotted a mistake or a change? Let us know below.

🔗 Also useful

🧾Wrong or high bill→📣Complaint about a supplier→📟Smart meter→🔄Switching supplier→📈Price increase→

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