ahorr.ai · Blog
Cambio de titular luz: qué revisar para no pagar de más
Respuesta rápida
To change electricity ownership without overpaying, you must review the contracted power and cancel unnecessary maintenance services before signing. In the Spanish energy market, this process is free and allows you to choose a more competitive tariff that fits your actual consumption needs.
En 30 segundos
- ✓Locate the 'CUPS' code and the current 'Potencia Contratada' in the header of the bill.
- ✓Compare the current power rating with your actual appliance needs to avoid paying for capacity you don't use.
- ✓Identify the 'Servicios Adicionales' section to spot maintenance insurance or emergency services.
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Transparencia y fuentes
Authorship, methodology and official sources.
Actualizado: 10 de enero de 2026
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Transparencia y fuentes
Authorship, methodology and official sources.
Actualizado: 10 de enero de 2026
Autoría
Equipo ahorr.ai
Auditoría energética (España)
Metodología orientada a decisión: separar coste fijo/variable, detectar extras y comparar opciones con números claros.
Metodología
- →Separamos coste fijo (potencia/término fijo), energía y cargos/impuestos.
- →Buscamos sobrecostes típicos: potencia sobredimensionada, servicios extra, lecturas estimadas.
- →Damos pasos accionables (qué tocar primero) con ejemplos orientativos, no promesas.
- →Enlazamos fuentes oficiales y marcamos lo que puede variar por comercializadora.
Información orientativa (España). Comprueba condiciones con tu comercializadora: precios, peajes, cargos e impuestos pueden variar.
El problema real detrás de cambio de titular luz: qué revisar para no pagar de más
When you move into a new home or office, the energy contract is often the last thing on your mind. However, utility companies often use this transition to keep expensive legacy conditions active.
Qué te hace pagar de más
The main culprits are 'vampire' services (insurance and maintenance) and oversized power ratings. These are fixed costs that you pay regardless of your consumption.
- ✓Maintenance insurance (often useless for new appliances).
- ✓Emergency repair services with high monthly fees.
- ✓Power ratings calculated for old, inefficient appliances.
Qué sí puedes cambiar
You have the right to modify the power rating and the tariff type during the ownership change. This is the best time to optimize the contract.
Método rápido (sin calculadora científica)
You don't need to be an engineer to spot the red flags in your new electricity contract.
Qué dato necesitas
Look for the 'Datos del contrato' section. Find the 'Potencia contratada' (measured in kW) and the 'Precio del término de energía' (measured in €/kWh).
Cómo interpretarlo
If your power is above 4.6 kW for a standard apartment, you are likely overpaying. If your energy price is above 0.18 €/kWh (before taxes), there are better options available.
Checklist antes de tocar nada
Before calling the utility company, ensure you have the evidence needed to demand a better deal.
Señales de riesgo
If the previous owner was paying more than 100€ for a small flat, there is a 'vampire' service or a very bad tariff involved.
Cómo evitar cortes/sorpresas
Always request a 'Cambio de titular sin subrogación' if you suspect there are unpaid debts, although a standard change is usually faster.
Caso real: lo que parecía normal… hasta que lo medimos
Numbers don't lie. Let's look at how a simple audit changed the financial outlook for a small business owner.
La pista
The freelancer noticed that even when the shop was closed for holidays, the bill was still 45€. This was the 'smoking gun' of high fixed costs.
La decisión
After an audit, they reduced the power to 3.0 kW and cancelled a 7€ maintenance fee, saving over 200€ per year without changing their habits.
Checklist para cambio de titular luz: qué revisar para no pagar de más
- ✓Locate the 'CUPS' code and the current 'Potencia Contratada' in the header of the bill.
- ✓Compare the current power rating with your actual appliance needs to avoid paying for capacity you don't use.
- ✓Identify the 'Servicios Adicionales' section to spot maintenance insurance or emergency services.
- ✓Check if the contract is in the 'Mercado Libre' or 'Mercado Regulado' (PVPC).
- ✓Verify if there are any pending debts from the previous owner before signing the change.
- ✓Decide whether to keep the current tariff or switch to a more competitive one during the process.
Symptoms of an Inefficient Contract Transfer
| Symptom | Hidden Cost | Recommended Action |
|---|---|---|
| Oversized Power | High fixed monthly charge | Request a power reduction (Bajada de potencia) |
| Maintenance Services | 6€ to 15€ monthly 'vampire' fee | Cancel all non-essential add-ons immediately |
| Outdated Tariff | High price per kWh (over 0.20€) | Compare with current top 3 market offers |
| Reactive Energy (B2B) | Penalty for low power factor | Install a capacitor bank if necessary |
Reducing power has a small administrative cost but pays off in less than three months.
The Freelancer's Trap: A Small Business Case
A self-employed professional took over a small commercial space. Instead of requesting a new contract, they opted for a simple name change. Three months later, the bill was consistently higher than expected despite low activity.
Hallazgos
- ✓Contracted power was 4.6 kW while real peaks never exceeded 2.8 kW.
- ✓A hidden 'vampire' maintenance service was charging 6.99 €/month.
- ✓The effective price was 0.23 €/kWh, significantly higher than current market alternatives.
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Preguntas frecuentes
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Disclaimers
- Informational tool; not financial advice.
- We don’t guarantee savings: these are estimates.