A third of workers admitted to going to work with a hangover, and 15% owned up to having been drunk at work, a study by Norwich Union has found.
One in 10 staff said this happened at least once a month, and one in 20 said that it happened once a week.
Of those who had had a hangover or been drunk at work, 85% confirmed it affected their performance or mood, with more than a third saying they found it hard to concentrate or were less productive and 42% feeling tired to the point of being very sleepy.
More than half thought their bosses and colleagues had noticed a change in their productivity as a result of drinking, while a quarter said they had felt embarrassed about something they had said or done in front of their boss and colleagues after drinking.
A fifth of people working in construction and 15% in wholesale and agriculture admit to going in to work hungover once a week.
Staff in labour-intensive roles admitted their alcohol intake not only affected productivity, but could also potentially threaten the health and safety of themselves and others.
More than six in 10 people working in manufacturing and more than four out of 10 in construction said they found it hard to concentrate with a hangover.
A third of construction workers and nearly a quarter in manufacturing also admitted they made lots of mistakes they had to rectify the following day.
The research found that nearly eight in 10 employers believe alcohol is the number one threat to employee wellbeing and is encouraging sickness absence.
Yet just 9% of workers share their bosses’ concerns, highlighting a wide gap in perceptions.
Dr Douglas Wright of Norwich Union Healthcare said: “It’s essential that companies have a robust drug and alcohol policy and procedure to tackle and, where possible, prevent any problems developing. This should include provision for support and, potentially, referral to appropriate facilities.”