The Trades Union Congress (TUC) says British workers lose out with just eight bank holidays a year, in comparison with the European average of 10.8.
And fewer bank holidays for British workers is in top of them getting the least statutory annual leave in Europe, according to the union's report published on Friday.
TUC General Secretary John Monks said: "This report shows that again British workers have been put at the bottom of the EU pile.
Happier workers
"But they need proper time off work as much as their European colleagues.
'UK workers have the shortest holidays and the lowest productivity in Northern Europe.
So offering more holidays makes sense for employers too - happier workers are more productive.'
Bank holiday entitlements
Britain - 8
Netherlands - 8
Republic of Ireland -9
Northern Ireland - up to 10
Italy - 12
Austria - 13
Spain - 14
Portugal - 14
Britain and the Netherlands have the fewest bank holidays among EU countries with just eight, compared with Spain and Portugal which have 14.
Not only do they get fewer bank holidays than in other countries in Europe but Britons have to rely on the generosity of their employers to be able to take the days off, the union said.
There is no statutory right for UK employees to take public holidays, or to be paid for taking them as time off.
And almost one in five employees in the UK is not paid for taking public holidays as time off.
EU workers get an average of 33 days off a year including public holidays and minimum annual leave days.
But for the UK the figure is as low as 20 days.