Smart Export Guarantee Payments and Tax
Written and reviewed by the Solar Installer Accountants editorial team. Last reviewed 22 August 2026.
Installers get asked whether export payments are taxable more often than almost anything else, usually at the point of quoting, and the honest answer has two halves. For an ordinary householder the answer is generally no. For a business it is generally yes.
That split is not a rule of thumb, it is written into the legislation and HMRC's manuals, and the conditions are specific enough to be worth knowing accurately if you are going to be asked at the kitchen table.
The Householder Exemption and Its Limits
There is a specific income tax exemption for domestic microgeneration, and it applies to individuals only. Two conditions have to be met: the system is installed at or near domestic premises occupied by the individual, and the individual intends that the electricity generated will not significantly exceed the electricity consumed at those premises.
The second condition is where it gets useful, because HMRC has put a number on it. Its guidance says a householder who does not intend to generate more than 20% in excess of their own domestic needs is unlikely to be regarded as intending to significantly exceed what they consume. So a system sized to the house is comfortably inside the exemption. A deliberately oversized array on a domestic roof, sized to export, is the case that needs thought.
The exemption can extend to a property that is not the individual's main home, provided it is used wholly or mainly as a separate private dwelling. It does not extend to companies, and it does not cover generation carried on as a trade.
Why a Business Is Taxed Differently
Where export income is received in a business capacity it is a business receipt on normal principles, and it goes into taxable profit like any other income. There is no equivalent exemption for a trade or a company.
That matters directly for two of your customers. A commercial rooftop array on a working building generates export income for the business that owns it, taxable in the ordinary way. And a farm, a village hall or a mixed-use property can sit awkwardly between the two, because the exemption is written around domestic premises occupied by an individual.
It matters for you as well if you put an array on your own premises or a demonstration system on your own roof. The relief on buying it runs through the special rate pool rather than full expensing, and the export income it produces is business income. Both sides need to be in the accounts, not just the one that saves tax.
The VAT Position
Two different answers, depending on which payment you mean. A generation tariff is not consideration for any supply at all, so it is outside the scope of VAT. Export payments are different: they are consideration for supplies of electricity, where they are made by a taxable person in the course of their business.
So a VAT-registered business exporting electricity is making a supply, and the VAT treatment follows from that. A householder within the domestic exemption is not in business and the question does not arise. Levelisation payments are outside the scope as well.
This is one to get right rather than assume, because the answer differs by payment type and by who is receiving it, and it is the sort of thing that sits inside a properly run VAT return rather than being decided at the year end.
What to Tell a Customer Without Advising Them
Two practical points are safe to state and useful at quoting stage. The first is that SEG and the older Feed-in Tariff export payments cannot be received at the same time, so a customer already on FIT export is not adding SEG on top. The second is that eligibility runs through certification: a solar PV installation up to 50kW has to present an MCS certificate or equivalent, under the scheme Ofgem oversees.
Beyond that, resist doing the tax for them. A householder with a normally sized system is almost always inside the exemption, and saying so in general terms is fine. A customer with an oversized array, a business property or a mixed-use building needs their own advice, and a payback figure that quietly assumes tax-free export income is a claim you do not want to have made.