Irish people work 90 hours more per year than the European Union average.
That is one of the key findings in a new report from the Dublin-based EU agency, Eurofound.
The study also finds that Irish workers, on average, only get 20 days holidays each year compared to 25.7 days for citizens of the first 15 EU member states.
Eurofound says with the addition of public holidays, 'high-leave' countries include Croatia with 41 leave days, Denmark with 39 days and Germany with 37.
These are compared with the figures for 'low-leave countries' - such as Ireland, Hungary and Estonia - all which come in at just 28 days annual leave.
The average figure for the EU28 is 33.8 days.
In terms of hours worked, the study finds full-time employees in the UK report the longest working week at 42.3 hours.
They are followed by employees in Cyprus (41.7 hours), Austria (41.4 hours), Greece (41.2 hours), Poland and Portugal (41.1 hours).
Ireland stands in the middle, with an average working week of 39 hours. Employees in Denmark report the shortest weekly hours at 37.8 hours.
This is 4.5 hours less per week than their counterparts in the UK - the equivalent of more than five working weeks per year.
The report also looks at working time across different sectors - including chemicals, metalworking, banking, retail, and public administration.
It finds that across all selected sectors, the member states that joined the EU in 2004 work significantly more hours than who were in the union up to 2004.
"The difference in working time between workers in the 28 EU Member States remains large and is especially marked between the 'older' 15 EU member states and the 13 new member states that joined the EU since 2004", Eurofound says.