Workers in the UK collectively spent £91bn a year on the costs they face specifically because of their job, according to research from Santander credit cards.
And those costs are rising. According to the research, work-related expenses including commuting, childcare, work clothes and computer equipment cost the average full-time employee £3,405 a year, swallowing up to 16% of a full-time worker's net income.
That compares to £3,218 in 2014 and £2,681 in 2013. Commuting is the most expensive part of being in employment, costing full-time employees an average of £1,087 annually.
To get to work by public transport, full-time employees have to pay an average of £1,357 a year, while motorists spend £1,238 a year getting to work. That includes £922 on fuel, £180 on parking and £136 on tolls/congestion.
Childcare is also a substantial cost, with the average outlay now at £960, although that hasn't increase significantly since 2014, the research found..
However, one in four people pay more than four times the average – as much as £3,910 a year.
Barry Naisbitt, chief economist at Santander UK, said: “With over 31m people currently working in the UK, employees are of huge value to the economy.
"Not only is this from the output of the work they produce, but also due to the substantial additional contribution they make through work-related products and services, to the tune of £91bn per year.
"From the money they spend on work clothes to the cost of childcare, employees re-invest a significant amount of the money they earn from work every month.”
The research, commissioned by Santander and conducted by Opinium Research in June, surveyed more than 2,000 adults.
Respondents were asked to estimate their annual and monthly spend on a variety of work-related expenses including transport. These averages were calculated to apply to the whole working population.
According to the research, in 2015 the average full-time worker spent £1,087 on commuting, £960 on childcare, £553 on food and drink, and £240 on phone bills.
They also spent £228 on 'personal grooming' spent only because of work, £140 on colleagues and clients, £104 on work clothes, £54 on computer equipment, and £38 on work equipment such as stationery.