Thousands of UK homeowners with solar panels are being warned they could face an automatic £100 fine if they miss the 31 January online self-assessment deadline.
Many households earn money through the Smart Export Guarantee by selling surplus energy generated from their panels back to the grid.
Combined with side-hustle income, this can push earnings above HMRC’s £1,000 tax-free trading allowance, creating a legal requirement to declare the income.
Rising numbers of solar panel owners at risk
Around 1.6 million UK households now have solar panels, with many earning over £300 a year through Smart Export Guarantee (SEG) payments.
George Penny, Energy Expert at The Solar Co explains, “With hundreds of thousands of Brits earning through solar, it’s easy to unintentionally exceed the £1,000 trading allowance, especially when combined with other side income.”
With 39% of the UK workforce now having side hustles, many homeowners may be unaware they need to declare this additional income to HMRC.
George has worked for years for The Solar Co, who provide renewable solutions for households across the UK.
Understanding the £100 penalty and escalating fines
The £100 fine is triggered automatically if an online self-assessment is not submitted by the 31 January deadline.
Penny warns: “Even a small delay can result in penalties, and after three months, daily fines of £10 can apply, escalating further after six and 12 months.”
For some solar owners, these fines could wipe out a significant portion of their annual SEG earnings, making timely filing crucial.
Practical steps to ensure your return is correct
George Penny recommends that homeowners calculate all sources of income carefully, including SEG payments and any side hustles, before completing their return.
He adds: “If you’re unsure whether your solar income needs reporting, it’s safer to declare it early rather than risk a fine.”
Additionally, keeping a clear record of energy statements and receipts can make filing faster and reduce the risk of errors, while setting reminders ahead of the 31 January deadline helps avoid last-minute problems.
