The average worker spends one pound in every eight - totalling £1,843 a year - on costs relating to their job, new research has revealed.
Britons collectively spend £66.9 billion a year on costs specifically related to their jobs such as food, travel, childcare, equipment and clothes, according to the study by Santander 123 World.
Researchers said that 12% of the disposable income of someone with a full-time job is typically swallowed up by these costs.
London's employees are the hardest hit, spending on average £3,561 a year. Workers in the East of England spend £2,542 per year and those in Yorkshire and Humberside spend £2,535.
Workers in the West Midlands incur the lowest costs at £1,668, followed by the East Midlands with £1,688, and the North East with £1,896.
The figures recorded before last week's hike in travel costs show workers already spend the most on commuting, forking out an average of £782 a year on public transport.
Drivers, however, spend more, with £829 spent on fuel, £65 on parking and £32 on congestion charges.
The one in five workers who pay for childcare spend £3,632 a year on childminders and nurseries.
Lunch and snacking sets workers back £410 a year, with a further £142 spent on work calls not claimed on expenses, £27 on computer equipment and £18 on stationery.
Employees shed more money by putting an average of £153 into their personal grooming, £83 into clothes and spending £77 on colleagues and clients.