What is the electrical certificate (boletín) and when you need it
The electrical installation certificate (CIE) is essential to connect power or increase capacity. Here's how to get one.
Updated July 1, 2026·5 min read
Quick answer
What is the electrical certificate (boletín) and when you need it
The electrical installation certificate (CIE) is essential to connect power or increase capacity. Here's how to get one.
What the electrical certificate is
The electrical certificate, officially the Electrical Installation Certificate (CIE), is the document proving that an installation complies with the Low Voltage Electrotechnical Regulation. Only a licensed installer can issue it.
When you need it
It is mandatory to connect supply in a new home, increase contracted power, after a major renovation, or when the utility requests it due to the age of the installation.
How to obtain it
A licensed electrician inspects the installation, takes the necessary measurements and registers the certificate with the administration. The process usually takes a few days.
Electrical installation certificate (boletín): Facts that change the decision
Before deciding, collect the use of the property, intended capacity, age, alterations and the retailer's or distributor's request. A useful survey or study explains how those inputs were obtained and the limits of its estimate.
The answer changes with the scope of alteration, supply type and whether the installation needs work before certification. Ask for a base scenario and another showing the effect of changed conditions.
Provide twelve months of bills or consumption readings where available.
Ask for access, space and capacity constraints to be identified in writing.
Check that equipment brands and model references match the technical sheets.
Electrical installation certificate (boletín): Evidence, scope and rules
Request a certificate from an authorised installer, installation details and TECI filing evidence where relevant. The scope, exclusions and responsibility for each procedure should be unambiguous.
In Andalusia the applicable certificate process uses TECI; whether it is needed in one case depends on the file. Do not replace documentary checks with a sales explanation.
Request a timetable separating survey, work, testing and document handover.
Keep drawings, work photographs, serial numbers and certificates received.
Confirm in writing which authorised professional signs where the work requires it.
Electrical installation certificate (boletín): Compare without shortcuts
A common mistake is ordering a document without an inspection or confusing a repair quote with certification. Compare equivalent proposals rather than headlines, and ask which assumption explains every difference.
A more complete option may be preferable even when it is not the shortest to read. Where there is electrical risk, do not manipulate anything to test a theory; arrange qualified help.
Compare materials, protective devices, labour and paperwork as separate items.
Ask which specific condition can create an extra charge and how approval works.
Review product and workmanship warranty as well as the fault-contact route.
What to verify
Use this list to turn the guide into specific questions before approving any work.
Installer authorisation for the work and any required certificates.
Exact scope, exclusions and final outcome in writing.
Permits, legalisation, registration and handover documents.
Itemised price, taxes, travel and possible extras.
Frequently asked questions
How much does an electrical certificate cost?
The price varies by installation but is usually between €100 and €200 for a standard home.
How long is it valid?
For new connections the certificate has a limited validity, so it is best arranged shortly before contracting supply.
Official source
Sources and regulations
Primary public sources used for the regulatory and administrative framework. Always check the current version and the procedure that applies to your case.