Copyright birminghammail
Solar experts have issued a warning to UK households with solar panels over a looming HMRC deadline that could leave homeowners with £100 fines. Paper self-assessment tax returns are due by Friday, October 31 deadline, potentially leading to 18,000 solar panel owners left with a fine. 1.6 million households make cash by selling solar energy back to the grid - pushing homeowners closer to the £1,000 tax-free trading allowance. The Solar Co director George Penny said: "After a record-breaking year for installations in 2025, 1.6m UK households now have solar panels, and hundreds of thousands of Brits are earning money by selling unused electricity back to the grid. Read more: Keir Starmer breaks silence on claims income tax will be raised at November Budget “While households can make over £300 a year through the Smart Export Guarantee (SEG), these payments can quickly tip some people over HMRC’s £1,000 tax-free trading allowance, creating a requirement to declare the income. “With 39% of Brits side hustling in 2025, an estimated 624,000 solar panel owners could therefore unknowingly be earning more than the £1,000 trading allowance. "And with HMRC figures showing that 2.89% of self-employed taxpayers still use paper-based tax returns, this means an estimated 18,033 solar panel owners could be facing a £100 fine if they miss this Friday’s October 31 self-assessment deadline. “Faced with this predicament, it’s crucial that solar panel homeowners check, before it’s too late, how much they’re earning - including any additional income from their SEG payments. "If the total exceeds £1,000 made between April 2024 and April 2025, solar panel homeowners could be at risk of being fined by HMRC. "Review your latest statements from your energy supplier as soon as possible. These show exactly how much income you’ve earned from selling power back to the grid, which is crucial in working out whether you may have surpassed your £1,000 allowance. “If this extra income, plus any further additional income you may earn from other side hustles, surpasses £1,000 between the April 2024 to April 2025 tax year, you must declare this with HMRC.”
