Employees took the fewest number of sick days in more than two decades last year, according to new research.
A report by the CBI said workers took 180 million sick days last year at an average of 6.4 days each - the lowest since the group's absence survey began in 1987 and down from the average of 6.7 in 2007.
The improvement was in part due to falling staff absence rates in the public sector where employees took an average of 8.3 days off sick last year - down from nine days recorded in the 2007 survey.
However, the figure was still 43% higher than the private sector's average of 5.8 days in 2009.
The total cost to the economy from sick days last year was estimated to be around £16.8 billion, besides indirect costs arising from the impact on costumer service and teamwork delays.
Katja Hall, the CBI's director of employment policy, said: "Although the rate of employee absence has fallen in the public sector, it is still a lot higher than in the private sector, and this issue should be addressed, especially given that the public finances are strained.
"We estimate that £5.5 billion could be saved by 2015-16 if the public sector matched the private sector's absence rate. Improved rehabilitation and workplace health policies are a key part of achieving this, but so is ensuring that absence, where it occurs, is justified."