Spain · consumer process
Changing electricity supplier in Spain: what actually happens?
The cables, meter and distributor normally stay the same. The incoming supplier arranges the commercial switch, while the customer’s job is to choose carefully, give valid consent and check the bills.
A supplier switch is an administrative and data-exchange process, not a rewiring project. The local distributor continues to operate the network and meter. The new supplier becomes responsible for the supply contract and billing after activation.
1. Compare and read before consenting
Use the same annual consumption, contracted power and solar assumptions for each offer. Check energy and power prices, duration, renewal, price changes, early-exit conditions, payment method and paid services. Save the tariff sheet and contract summary with the date.
Do not give verbal or online consent merely to receive information. Confirm the legal company, exact tariff and complete annual estimate first. Spanish rules require express consumer consent for a switch.
2. Prepare the supply information
The incoming supplier will normally need the contract holder’s details, supply address, CUPS, current bill information, bank details for direct debit and contact information. A solar supply may also need the correct self-consumption and surplus-compensation information.
Check that the contract holder and CUPS are correct. If the contract holder must change, ask whether that will be processed with or before the supplier switch and whether different evidence is required.
3. The incoming supplier starts the switch
Under Royal Decree 88/2026, the process begins when the customer formalises the new supply contract. The incoming supplier must send the request to the distributor within the prescribed process. The consumer may specify an effective date; otherwise the change should occur as soon as possible.
The current general rule gives an electricity consumer the right to change supplier within a maximum of ten business days from contract formalisation. Exceptionally, complex field work can extend this by five business days. This updated rule replaces older consumer material that often quoted 21 days for the switch itself.
Normal sequence
One contract, several parties
- Customer
- Chooses and consents
- Incoming supplier
- Submits the switch
- Distributor
- Validates and activates
- Outgoing supplier
- Issues final bill
The electricity should continue through the same connection during a standard commercial switch.
4. Understand readings and bill timing
The distributor provides the switching information and the reading used to close the old supply period. The 2026 regulation allows the distributor up to 21 days from the change date to send the corresponding reading to the outgoing supplier. That 21-day reading provision is different from the ten-business-day switching right.
Save or photograph the meter reading around the effective date where practical, and download distributor interval data. It provides evidence if the final and first bills appear to overlap or leave a gap.
5. Review the right to withdraw and any exit cost
For a distance contract—such as online or telephone contracting—review the withdrawal information supplied with the agreement. CNMC guidance explains a 14-day withdrawal period in the normal distance-contract context. Ask how an urgent activation request affects that process.
The switching process itself is normally free, but the outgoing contract can contain a valid early-termination consequence or a separate service contract. Cancelling a maintenance service may require a distinct instruction. Read both agreements.
6. Solar customers need an extra check
The new contract should reflect the self-consumption arrangement and the chosen treatment of surplus. Ask the incoming supplier to confirm whether existing registration information will transfer automatically and what evidence is required for compensation. Keep the regional registration, electrical certificate and previous compensated bill available.
A change of supplier can expose an existing data mismatch between regional authorities, the distributor and the supplier. If export credit does not appear immediately, determine whether the issue is the contract, registration, meter data or processing date before changing again.
7. Check the outgoing final bill
- Correct closing date and meter reading.
- No consumption billed after the new supplier’s start date.
- Discounts and services applied only for their valid period.
- Any early-exit charge matches the contract.
- Final solar export is credited under the old terms.
8. Check the first complete new bill
Confirm supplier legal name, tariff, energy prices, power prices, contracted levels, billing dates, taxes, meter cost and services. For solar, reconcile imported and exported kWh and the compensation rate. Compare the first bill with the saved contract summary, not with a screenshot of an advertisement.
If something is wrong, complain in writing to the supplier and retain the complaint reference. The bill should identify customer-service and complaint routes. Escalation depends on the dispute and region, so use the relevant consumer or energy authority if the supplier does not resolve it.
Official sources
- BOE — Royal Decree 88/2026, Articles 18–19 on supplier switching
- CNMC — consumer guide to changing electricity or gas supplier
- CNMC — supplier switching in Spain
Reviewed 28 August 2026. The ten-business-day rule is taken from the current 2026 regulation; special cases can differ.