The East of England racked up one of the highest totals of undeclared taxable income in the last year, a new study shows.
At an average of £7,371 per worker, the region had the second highest total in the UK, surpassed only by London's total of £8,991 per worker.
According to the survey of 2,000 adults by comparison site Finder.com, more than one in seven Brits (13.7%) admit earning money they will not declare as part of their taxable income, making an extra £4,124 on average last year.
It follows an announcement by HMRC that one in 15 people missed the self-assessment deadline this year.
Finder.com says more than 5.7 million Brits neglect to declare their full taxable income, resulting in an estimated £23.5bn being made off the books.
It claims men are twice as likely to avoid paying tax, with 19% failing to declare their full earnings to HMRC compared to 8.3% of women.
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