Research from the TUC (Trades Union Congress) reveals that unpaid overtime means IT workers are effectively working for free until 9 March every year.
Managers in IT work an average of 9.3 hours a week in unpaid overtime. IT professionals work an average of 6.3 hours a week for free and so start being paid on 22 February. IT support staff and technicians do slightly better with average overtime of 5.5 hours which means they start getting paid on 13 February.
The TUC is calling for workers to work only the hours they should this Friday 27 February to show bosses the value of their free work.
TUC General Secretary Brendan Barber said in a statement: "We're not calling on Britain to turn into a nation of clockwatchers, but too many of Britain's bosses depend on the unpaid overtime of their staff take it for granted and never show their appreciation."
Top civil servants, corporate managers and CEOs do the most unpaid overtime, 12.5 hours a week, and don't start getting paid until the 27 March. Teaching professionals are next with an average of 12 hours a week.
More than five million people in the UK work unpaid overtime, giving bosses £23bn of free work a year.
Shelf fillers and telephonists are least likely to put in hours for free - although they still clock up 2.2 hours a week.
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