Experts cautioned household finances have become strainedRory Poulter08:46, 28 May 2026Brits risk falling into a 'tax trap' without realising it as the cost of living squeeze continues to batter household budgets. Millions across the UK are juggling income to cover food, rent and utility bills.‌Fresh data reveals one in four adults now has an additional income source, with many selling unwanted goods online, taking on second jobs or setting up small enterprises to bridge the shortfall caused by rocketing living expenses. Research by ecommerce marketing platform Omnisend discovered that 25% of UK adults now supplement their income, while over half said they'd begun doing so to help pay for essentials such as bills and groceries.‌The study calculated that side hustles are now pumping around £8.5billion monthly into the UK economy. Yet most people aren't raking in huge amounts. Roughly two-thirds of those with side hustles earn £500 or less per month after expenses, with many bringing in under £100. Experts cautioned the trend demonstrates how strained household finances have become, with one stating the findings 'should ring alarm bells'.‌Marty Bauer, ecommerce expert at Omnisend, said: "For a lot of people, side hustles are no longer about turning a hobby into a business. They are about making ends meet. An extra £100 or £200 a month might not sound life-changing, but when food, fuel, rent and bills are all competing for the same income, it can be the difference between falling short and getting through the month."He noted that many people were generating income by selling items through platforms such as eBay, Vinted and Facebook Marketplace rather than making substantial business investments.‌Mortgage specialists said they were increasingly encountering applicants depending on multiple revenue sources. Rohit Kohli, director at The Mortgage Stop, told Newspage: "Two or three years ago, maybe two in 10 clients had an extra income stream. Now it feels closer to half. It tells you normal wages are not keeping pace with real life. The frustration is that people are working more, but not always feeling the benefit."Hannah Vandervennin, mortgage adviser at The Mortgage Consultancy, cautioned that lenders were frequently hesitant to include additional earnings when evaluating affordability. She explained: "The mortgage market hasn't caught up. Most of it won't count on a high street lender's affordability assessment. Their underwriting is built around predictable salaried employment."Article continues belowTax and finance specialists also cautioned that many people may be unaware that supplementary income can still attract attention from HMRC. Michelle Lawson, director at Lawson Financial, said: "The rising costs of living and general household financial pressures are pushing more people to extra work or additional income streams. The UK has some of the longest working hours in Europe, the most expensive bills and the least rewards."Under existing HMRC regulations, Brits can earn up to £1,000 annually through trading activities before being required to declare the income under the Trading Allowance. Kate Underwood, founder of Kate Underwood HR and Training, cautioned: "HMRC pulls data directly from eBay and Vinted now so flying under the radar isn't the option it once was."Meanwhile, Mitali Deypurkaystha, author and AI strategist at Impact Icon AI, suggested the figures revealed that Britons were sacrificing valuable leisure time simply to make ends meet financially. She said: "That should ring alarm bells about the death of downtime in modern Britain. Side hustles used to be about extra holidays or pursuing a passion project, but for millions, they now fund food bills, rent and heating."