That quick evening email may seem innocent, but it can have a surprisingly negative effect.

In recent years, increased use of smartphones, tablets and other portable tech devices has made it possible to reach employees essentially at any time of the day or night.

You can contact employees outside of normal work hours. However, today’s 24-hours-a-day connectivity has raised a pressing question: Should you?

Several recent studies have identified work-life balance as a key factor in employee satisfaction — as well as a rising concern. Eighty-nine percent of U.S. workers, for example, said work-life balance has become a problem, according to a Society for Human Resource Management survey.

A study published in the European Research Studies journal found employees in Europe felt work-life balance had become increasingly difficult to manage, but was increasingly important, particularly to Millennials, according to Psychology Today.

The study found that employees who feel they are in command of their working environment experience less stress-related illness. Their employers experience less turnover.

Work stress concerns have prompted some countries to issue new regulations in the past few years. In Germany, employers aren’t allowed to contact employees when they’re on vacation, according to NPR. Late last year, German Labor Minister Andrea Nahles proposed a regulation to reduce workplace stress, which suggested banning employers from contacting workers after hours.

A 2014 deal signed by unions and employers’ federations in France stipulated that digital and consultancy sector workers could not be contacted before 9 a.m. or after 6 p.m., according to the BBC.

Letting employees decompress outside of the office can provide significant retention and productivity pay-offs. Yet when managers and coworkers need a quick answer — or to fulfill a client request— the temptation to contact employees, is, in many cases, irresistible.

If your organization is struggling to balance business demands with a positive work-life balance, the following tips may help you ensure work gets completed — without having to contact employees when you shouldn’t.

Let employees know you don’t need an immediate response: Gallup found that half of workers who said they frequently emailed outside of the office experienced a substantial amount of work stress. Increased telepressure — the expectation that you’ll check and respond to e-mails outside of work — can cause physical and cognitive burnout, resulting in poor sleep and additional sick days, according to a recent study published in the Journal of Occupational Health Psychology.

To avoid productivity lapses caused by employee absences, study co-author Larissa Barber, assistant professor of psychology at Northern Illinois University, recommends including no-pressure phasing, such as “No need to respond to this message” or “I look forward to hearing from you tomorrow” in after-hours emails.

An always-in-contact employee may be an overworked worker: If an employee doesn’t feel he can take a few days, or an evening, off and still complete his work, it can be an indication that the individual is overloaded and may soon become overwhelmed.

A recent international Monster.com survey found that 42 percent of workers had left their job due to stress (More than a third cited work-life balance issues, and 39 percent said it was because of their amount of work.) Keeping employees engaged — but not overworked — can help increase retention levels.

Majority rules: Ultimately, your organization’s after-hours communication policy will be heavily influenced by your company culture, according to Inc. If most employees, including high-level executives, are very visibly working late, employees are more likely to understand that’s the norm. Resentment can become an issue, however, if only a small group is subject to after-work requests.

In some instances, contacting employees after-hours may not be a bad thing. Long hours and less vacation time have equated to reduced well-being in several studies, according to the Harvard Business Review; however, when workers are engaged, even with those factors in play, their well-being remains strong.

The key difference? Out-of-office communication needs to be the employee’s choice — not a requirement. Dedicated workers often understand that if a matter depends on them, contacting them outside of work may be necessary.

However, if it becomes a nightly occurrence, or an employee is out of the office for a week and specifically asks to not be called, employers should respect that wish. If you don’t, you risk endangering that employee’s job satisfaction — and potentially, the person’s future with the company.

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