Despite margins often being tighter, work-related stress links directly to the size of a business - with workers at smaller companies feeling less stressed, according to new research.

Businesses employing no more than four members of staff were the least likely to feel work-related stress, at 45 per cent of employees, according to a study of 3,000 UK workers carried out by Perkbox .

This figure increases to 57 per cent for small businesses (5 - 50 staff) and again to 62 per cent for medium sized organisations (51 - 500 employees).

Workers at the largest sized businesses, with more than 500 members of staff, reported the greatest instances of staff experiencing workplace stress, at 65 per cent.

One in five (21%) UK workers said they experience moderate to high levels of work-related several times per week. Many businesses could see dips in productivity as a result, with 25 per cent of stressed UK workers struggling to be as productive at work as they would normally be.

Almost half (45 per cent) of UK workers say that their workplace doesn't have anything in place to help reduce employees' stress levels and improve their mental wellbeing.

Chieu Cao, CMO of Perkbox, said: "Interestingly, it's those in micro businesses that are the least likely to experience work-related stress, despite those in smaller companies feeling the direct impact of business tensions or losses.

"It's more than clear that a happy workforce is a productive workforce. It's surprising to see that in 2018, employers are not doing more to ensure a happy, healthy and productive work environment, not only to protect staff against stress but also to gain the very best results from the driven workforce."

Sam Holliday, Federation of Small Business (FSB) Development Manager added: "I think although it is encouraging to see that stress levels among people in our SMEs are lower than for those at larger businesses it is hardly a cause for celebration when it is still as high as 45 per cent for micros and 57 per cent for small business employees.

"What these figure show is that stress is a universal and growing issue in business and although some stress is inevitable in the workplace when it grows to be intolerable it is bad for business and, more importantly, bad for the mental health of the person suffering from it.

"The issue has become so large in the SME community that the FSB has launched its own Wellbeing in Small Business campaign (see https://www.fsb.org.uk/standing-up-for-you/our-campaigns/wellbeing-hub/wellbeing-in-small-business-hub) and as an example of how widespread the problem is, an event on the subject we have organised in Bath next month has already attracted 60 sign-ups. This is clearly an issue that all businesses, of whatever size, must take seriously."