Firms have been urged to encourage their staff to literally switch off when they finish work after new research showed that constantly checking smartphones and other gadgets for emails and messages increased stress levels.
A study by psychologist Richard Balding revealed that stress was likely to increase the more someone checked phones.
People who were most stressed experienced "phantom" alerts and checked their phone even when there were no new messages, it was found.
Research among more than 100 public sector, retail and other workers and university students discovered a "helpful-stressful" cycle, with phones usually bought to manage a workload.
Once an individual starts to use a smartphone, any benefits in managing a workload were displaced by pressure to check and respond to messages from friends in the new expanded "virtual social life", said the report.
Mr Balding urged firms to consider the problem seriously, adding: "Smartphone use is increasing at a rapid rate and we are likely to see an associated increase in stress from social networking.
"Organisations will not flourish if their employees are stressed, irrespective of the source of stress, so it is in their interest to encourage their employees to switch their phones off, cut the number of work emails sent out of hours and reduce people's temptation to check their devices."
The research will be presented today at the British Psychological Society's annual occupational psychology conference in Chester.