The study by the Canada West Foundation says 40 per cent of employees could perform better if they improved on basic skills like math, reading and writing.
"We are probably missing out on some major productivity gains that could be realized if people didn't have to take so much time to work out things, if people didn't have to do things over," said Janet Lane, co-author of the report.
Lane says it's difficult to put a number on how much the skills shortage is costing the economy, but it could be in the hundreds of millions.
The report says roughly half of people who didn't finish high school are missing such essential skills, while 30 per cent of university graduates are also lacking skills needed for their jobs.
It also says immigrants have skills shortages of between 10 to 16 per cent higher than the non-immigrant population.
Using 2011 data from Statistics Canada and the OECD, the study compared what jobs skills are needed with what skills Canadians actually have.
The Canada West Foundation says employers should invest in training to increase productivity, efficiency and safety in an increasingly competitive global economy.
"Our competitor countries are raising skills faster than we are, and so a lot of jobs have already been lost overseas," said Lane. "A lot of jobs will continue to leave the country if we do not adequately improve the value-add of jobs we have in the country."
It also recommends that the education system put more emphasis on essential skills training in public and post-secondary school.
"It's a problem, but it's also an opportunity for us to upgrade the skills of our workforce," said Lane.
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