How to Register Solar Panels in the UK: DNO & MCS (2026)

Your installer leaves, the panels are bolted down, and the obvious thought is: done. It isn't. Registering solar panels in the UK is actually six separate bits of admin — your installer quietly handles three of them, and three are on you.

Skip the wrong one and the cost isn't abstract. Forget to apply for the Smart Export Guarantee promptly and you give away weeks of free electricity to your supplier. Forget to tell your insurer and a claim years from now can be refused outright — for anything, not just panel damage. None of this is complicated. It's just never written down in one place, which is what this is for.

What actually happens after your solar panels go in?

Six separate processes start the moment your system is switched on, and your installer runs three of them without you lifting a finger. DNO notification, your MCS certificate, and Building Regulations compliance are all handled as part of a standard installation — they're the reason a competent installer costs what they cost.

The other three are yours: applying for the Smart Export Guarantee, telling your home insurer, and — only in specific cases — getting your mortgage lender's sign-off. Of those three, the SEG application is the one with an actual deadline pressure, because payment timing depends on when you apply, not when your panels started generating. The rest of this guide goes through all six in the order they typically happen, starting with the one that confuses the most people: the DNO.

Do you need to register your solar panels with your DNO?

Yes — every grid-connected solar installation in the UK has to be registered with your local Distribution Network Operator, the company that owns the cables in your street, not your energy supplier. Which form applies depends entirely on the size of your inverter.

Systems with an inverter rated at 3.68kW or below per phase (11.04kW for three-phase supplies) fall under G98 — a "connect and notify" process. Anything larger needs G99, which requires sign-off before installation begins. Most domestic systems sit comfortably under that 3.68kW line, so if you're reading this wondering which one applies to you: probably G98.

For G98, the rule under Engineering Recommendation G98 is straightforward: install first, then your installer notifies the DNO within 28 days of commissioning, using a standard form. You'll sometimes see this described the other way round — one well-known supplier markets a "we notify before your panels go in" process as a courtesy. That's their choice, not the regulation. Either way, it's your installer's job, not yours.

If your system is large enough to need G99 instead — anything above that 3.68kW per phase line — the short version: your installer submits a form to the DNO before any work starts, approval typically takes 4 to 8 weeks (rarely up to 12), and a fast-track route can bring that down to about 2 weeks. Submission is free, though your installer may add their own admin fee. Rejections are rare, and almost always come down to the local grid being at capacity rather than anything you did wrong.

If you've seen headlines about UK solar grid connections being shaken up in 2026, that's real — it's just aimed at solar farms and commercial-scale projects fighting for capacity, not your roof. Residential G98 systems are explicitly unaffected. The chaos in the news is for people building actual fields of panels, not whoever's fitting 14 of them above your garage.

This is separate from planning permission, which is a council matter rather than a grid one — our UK solar panel planning guide covers when you do and don't need it.

What is an MCS certificate, and why does losing it matter so much?

An MCS certificate is the document proving your installer and your equipment meet the UK's official quality standard for small-scale renewables — the Microgeneration Certification Scheme. Without it, you cannot claim Smart Export Guarantee payments, for the entire life of the system.

You don't apply for this yourself. Your installer issues it as part of the job, alongside your G98 or G99 paperwork. The part worth taking seriously is what happens if it goes missing or never existed: a system installed without MCS accreditation — including one built with second-hand panels — cannot be certified retroactively. There's no fixing it after the fact.

Think of it like a parcel with no tracking slip. The courier doesn't care that you definitely sent something — no slip, no delivery. No MCS certificate, no export payment, no matter how well your panels are actually performing on your roof. If your certificate is genuinely lost rather than never issued, your original installer can usually reissue it, or you can apply directly to MCS for a £36 admin fee.

Do solar panels need building regulations sign-off?

Yes — solar installations sit under Building Regulations for two separate reasons: whether your roof can structurally take the extra weight, and whether the electrical work meets Part P safety standards. Both get checked, just not usually by you.

In practice, an MCS-certified installer is normally also registered with a Competent Person Scheme, which lets them self-certify their own electrical work and notify building control on your behalf. For a standard domestic rooftop system, this closes the loop without you needing to contact your local authority's building control department separately. Exactly which document lands in your inbox at the end of this varies by installer and competent-person scheme — in the standard case, their registration is what does the job, not a separate certificate you need to go looking for.

How do you actually apply for the Smart Export Guarantee — and why does the date matter more than the rate?

You apply directly to any licensed SEG supplier — it doesn't have to be the company that supplies your electricity — and the date your application lands is what your payments get backdated to, not the date your panels switched on.

To apply, you'll need three things: your MCS certificate, your installer's G98 notification confirmation (or G99 approval from the DNO if your system needed that route), and proof of ownership — a purchase receipt, or evidence the panels were included when you bought the house. If you rent rather than own the property, you'll need written landlord permission instead.

Rates vary enormously by supplier, from roughly 1p up to over 30p per kWh depending on who you sign with and when you export — our UK solar panel grants and schemes guide has the current supplier-by-supplier comparison. Not sure what your own export figure should even be? PV-Freund's solar export calculator gives you that number for your specific roof in a couple of minutes.

What matters more than the rate is speed. Octopus, for example, processes its side of the paperwork in about two days. What actually takes time is your DNO issuing an export MPAN — the 13-digit reference confirming your meter is yours to export from — which can take 1 to 4 weeks on its own, with the full process landing somewhere between 2 weeks and 12 weeks depending on the supplier. That's less "your supplier is slow" and more "the sorting office is the holdup, not the postman."

Here's the bit that actually costs you money: payments are backdated to your application date, full stop. Every week between your system being commissioned and you actually submitting that application is a week of electricity exported to the grid for free. Your supplier will not send you a thank-you card for it. The moment your installer hands you the MCS certificate and your DNO confirmation, send the SEG application off that same day — don't let it sit in an inbox while you wait for things to feel fully "sorted." Our UK solar payback calculation shows what a few months of unclaimed export is actually worth over a system's lifetime.

Do you need to tell your home insurer about solar panels?

Yes — solar panels count as a "material change" to your property, and not disclosing them can mean an insurer refuses any claim, not just one related to the panels.

Standard buildings insurance usually does cover solar panels as a permanent fixture of the home, but only if your insurer actually knows about them. Naturesave, a UK insurer that specialises in homes with renewable energy installations, warns that failing to declare a solar system can invalidate your policy outright — a storm, flood, or fire claim can be refused not because of the panels themselves, but because the insurer was never told the risk profile of the house had changed. Notify your insurer before installation if you can, or immediately after — don't wait until your renewal date rolls around, since that's the gap where an undisclosed change becomes a problem if something happens in between.

There's a second, less dramatic reason to do this: panels add to your home's rebuild cost, and your buildings insurance sum needs to reflect that to avoid being underinsured. That's a separate issue from disclosure, but it's worth sorting in the same phone call.

Will solar panels cause a problem with your mortgage?

If you own your panels outright, almost certainly not. If you're leasing them under a "rent-a-roof" scheme, your lender's consent isn't optional.

UK Finance's Lenders' Handbook treats a roof-space lease for solar panels the same as any other lease of part of your property. In England and Wales, this is addressed directly under the handbook's standard requirements, and most lenders' mortgage conditions require their consent before you sign a lease agreement for your roof. Northern Ireland works differently again — a lease of roof space isn't acceptable to lenders there at all, and a "lease of rights" arrangement is required instead. Scotland currently has no specific published guidance either way.

Reading the small print on this is nobody's idea of a fun afternoon, but it's a far better afternoon than the one where a buyer's solicitor asks about it three weeks before completion and nobody in the chain has an answer. Getting leased-panel consent wrong isn't just a breach of your mortgage terms — it can make the house genuinely difficult to sell later, because your buyer's own lender may simply refuse to lend with someone else's panels still bolted to the roof.