What Is an MCS Certificate, and What If You’ve Lost It?

An MCS certificate is the document that shows your solar panels, battery or other small-scale renewable system was installed by an MCS certified installer and registered with MCS. You will usually need it to get paid for exported electricity, and buyers’ solicitors often ask for it when you sell. If you have lost it, the original installer can provide a copy, and the MCS Helpdesk can check whether one exists for your address.

Key points

• MCS certifies installers and products for small-scale renewables, including solar PV and battery storage.

• Your installer should issue your MCS certificate within 10 working days of the installation being completed.

• Export tariffs under the Smart Export Guarantee normally require MCS certification or an equivalent.

• If it’s lost, ask your original installer first. If they are no longer certified or have stopped trading, the MCS Helpdesk can help.

• Keep it with the rest of your system paperwork: electrical certificate, network operator notification, warranties and manuals.

What the certificate shows

The MCS certificate is the record of your specific installation. It ties the system to your address and to the installer who registered it, and confirms it was registered with MCS at the time it was completed. It isn’t a warranty, and it isn’t a guarantee of how much the system will generate. It’s evidence that the job was done by a certified installer using the scheme’s requirements.

Why you need it

Export payments. Suppliers offering the Smart Export Guarantee will normally ask for your MCS certificate, or an equivalent, before paying for exported electricity. Our guide to the Smart Export Guarantee explains how to apply.

Selling your home. Buyers’ solicitors usually ask for the paperwork behind a solar system, and the MCS certificate is one of the first things on the list. Our guide to buying a house with solar panels covers what a buyer will look for.

Older Feed-in Tariff systems. If your system is on the Feed-in Tariff, the MCS certificate was part of how it was accredited. Changes to the system can affect your payments, so read our guide to keeping your Feed-in Tariff when you upgrade before any work is done.

Warranties and insurance. Some product warranties and insurers ask for proof of how the system was installed.

You’ve lost it, or never had one: what to do

MCS’s own guidance sets out the route.

1. Contact your original installer. Whether you never received the certificate, need a copy, or need a correction, MCS says to go to the installer who fitted the system first.

2. If the installer can’t help, because they are no longer MCS certified or have stopped trading, contact the MCS Helpdesk on 0333 103 8130. MCS says the Helpdesk will support you with your certificate query.

3. To check whether a certificate exists at all, the Helpdesk can look it up. Have the technology type (for example solar PV or battery storage) and the full address including postcode ready.

If a certificate turns out never to have been issued, that is worth knowing early, especially before you sell or apply for an export tariff. Our guide on what to do when your solar installer has gone bust covers the wider paperwork picture when the installer has disappeared.

Does work on an existing system change the certificate?

It can. An extension, such as more panels or a battery, should be installed and certified by an MCS certified installer, which is what export payments on the new equipment depend on. Replacing equipment may need the records updating, particularly on Feed-in Tariff systems. MCS rules also require products installed under the scheme to be new and unused. That matters if panels are taken off for roof work and refitted: panels refitted on the same roof are very unlikely to count as a new MCS installation. Our guide to removing solar panels for roof repairs explains what that means for your paperwork.

What other paperwork should you keep?

Alongside the MCS certificate, keep together:

• The electrical installation certificate for the work.

• Confirmation that your network operator was notified, or approved the connection.

• Product warranties for the panels, inverter and any battery, and the installer’s workmanship warranty.

• The handover pack, manuals and the system design, including the generation estimate.

Our guide to solar and battery warranties explains the different warranties you should have.

Frequently asked questions

Is an MCS certificate a legal requirement?

There’s no law requiring one to own solar panels. In practice you’ll normally need it for export payments, and a missing certificate can slow down a house sale.

How long should I wait for my MCS certificate?

MCS says installers should issue it within 10 working days of the installation being completed. If it hasn’t arrived, ask your installer.

Do batteries get an MCS certificate?

Battery storage can be installed under MCS by an installer certified for it. Solar Panels London is MCS certified for both solar PV and battery storage.

Can I get a certificate for a system that was never registered?

Not simply by asking for one, because the certificate records an installation done under the scheme by a certified installer. If yours was never registered, speak to the MCS Helpdesk about your options.

Book a solar system inspection. If your paperwork is missing or your system needs checking before a sale, we can inspect it and tell you where things stand.