21 signs your best employee is about to quit

Most bosses are caught off guard when facing a mass employee exodus, and the same can happen when just one valued employee resigns.

"As the boss, it's important to watch for the symptoms of an impending departure so you can address the issues before it's too late," says Lynn Taylor, a national workplace expert and the author of "Tame Your Terrible Office Tyrant: How to Manage Childish Boss Behavior and Thrive in Your Job." "Losing even one valued employee can disrupt your business, not to mention losing several team members. And if you're running a small company or startup, these losses can destroy your business."

Michael Kerr, an international business speaker and author of "The Humor Advantage," agrees. "Losing employees can create a substantial impact on everything from service delivery to scheduling. It can impact the culture in a team in a negative way. And there's a substantial cost and time commitment involved in replacing and training new employees, so the more time a manager has to prepare for the changes, the better."

Taylor and Kerr shared 21 signs that one of your best employees is about to quit. Of course, just because you notice these signs doesn't mean they're definitely about to jump ship ... but it could, so you'll want to keep an eye out and act before it's too late.

1. There's a change in their appearance

If they start dressing unusually sharply, it may be because they are slipping out to job interviews during or after work, says Kerr.

"Also, if someone is unhappy in their job, they may begin to dress down because they feel that no one is really paying attention anyway - or because they just don't really care anymore," adds Taylor.

2. You hear other companies are interested in them

If this is your best employee, it's not so surprising that they're highly sought-after in their field. Once you hear other companies are requesting meetings with this person, you may have something to worry about.

3. They start taking more time off

If this employee is normally doesn't miss work, but then begins calling in sick more often, or using up their vacation days sporadically, it may mean they are feeling very disengaged at work, possibly even to the point of using the time off to search for other employment, says Kerr.

"And using up their sick days and vacation time (and even getting a lot of dental work done suddenly) might be a red flag that they are getting ready to jump ship and want to make sure they max out any benefits they feel owed to them."

4. They show a drop off in any interest in work

Have you noticed that one of your top employees has stopped offering helpful suggestions or ideas at meetings, they offer little input into new projects, or seem suddenly disinterested in any of the broader details related to work?

"This can be a sign they've lost their mojo and no longer really care what happens down the road because they know they won't be there in the future," Kerr says.

5. They were recently passed over for a promotion or a raise they deserved

When someone is up for a raise or promotion (that they deserve) and they don't get it, it can be very frustrating and discouraging.

The employee will likely feel undervalued and may be inclined to go look for employment with a company that would appreciate and reward them for their contributions.

6. They lack a sense of humor

Employees who are about to bail may no longer joke around, says Taylor. "Their demeanor is more straightforward and factual versus friendly and lighthearted. Perhaps this is because they're less worried about appearing supportive or trying to impress anyone."

7. You can read it in their body language and facial expressions

Subtle clues might give hints that your employees are either disengaged or even feeling guilty because they've been job hunting and they know that they are not sticking around for the long run, Kerr explains.

8. They seem distant

Do you feel a sudden chill when you approach one of your employees? "The first few times, you chalk up to their having a bad day. Then you notice it among more team members ... more frequently," says Taylor. If this is the case, one or more employees may be preparing to leave.

9. They've been demoted

Similarly to being passed over for a promotion, an employee who is demoted will likely feel pretty dejected and may decide to take their talents elsewhere. If they happen to be one of your top employees, a demotion can be especially difficult and frustrating for them.

10. There's a noted change in attitude

They may become more irritable, or they may make more sarcastic comments than normal about work-related issues, revealing a lack of fundamental belief in the direction the company is headed, says Kerr.

A sudden lack of enthusiasm is also a big sign you may be losing one or more of your employees, Taylor adds.

11. There are changes in their behavior

If they are acting differently - maybe they're suddenly keeping to themselves more and more, or they begin going out to lunch with coworkers every day - the employee may be pulling away from work or commiserating with colleagues.

"If any team members who rarely went to lunch together before are now doing so, they may be discussing their plans to move on," says Taylor. "Seeing new behavior in who goes to lunch and how often, however, is certainly no cause for concern if other signs are not evident."

12. They're underpaid

If you know for a fact that this employee is worth more than your company is paying them ... and you think they know it, too ... they may be looking elsewhere. Feeling like you might be underpaid can be one of the most disheartening aspects of work.

13. They tell you about major changes on the home front

If there's a major disruption in their family life, this may lead to them looking for new opportunities for a host of reasons (to be closer to home, for example, or to work in a less stressful environment), Kerr explains.

14. Their productivity drops

If an employee who is normally extremely productive and punctual suddenly starts turning reports in late, or their sales have fallen dramatically, something might be going on. "Any behavioral changes that point to 'presenteeism' - the phenomenon of employees showing up at work without being fully present - are huge red flags," says Kerr.

15. They approach conflict differently

When people are ready to bolt, they may change how they handle disagreements, Taylor explains. "If they tended to push back before, they may no longer do so because they don't feel it's worth the bother. They have emotionally checked out."

However, someone who was generally agreeable before may become more argumentative out of frustration or resentment, she says.

16. They're uncomfortable discussing long-term projects and deadlines

If your employees are seeking greener pastures, they will become visibly uncomfortable discussing projects that are several months out, says Taylor. "When longer-term deadlines involve them directly, they'll attempt to be noncommittal or vague."

17. Colleagues tell you they think something's going on

If your coworkers approach you with concerns that something's changed or "something's going on" with a specific employee, they may be on to something.

"Other colleagues closer to the action may read the signs well before you do, so if they bring concerns forward, pay attention," says Kerr.

18. They stay under the communications radar

"If one of your team members is contemplating resignation, they're less likely to communicate often - by email, in person, or in general," says Taylor. "The thinking is that, to the extent they're less accessible, they won't risk being put on the spot ... answering sensitive questions that could jeopardize their job when they're not yet ready to move."

19. Their schedule suddenly changes

When they start keeping unusual hours - working later, arriving late, shifting their hours in any noticeable way - it could be because they are searching for work or interviewing with other employers while still trying to balance their current workload, says Kerr.

20. You inquire about possible issues, but get little feedback

Do they seem closed off? Are they not willing to work through issues with you?

"If one of your team members or several of them already have one foot out the door, they'll act as if nothing is wrong when you address any issues," says Taylor. This may be because they have already shut down and mentally moved on.

21. You have a bad gut feeling

If you feel awkward moments in your office more often or a discomfort around your team you can't explain, this may be a sign they're about to quit. "Your instincts count for a lot and most people don't put enough stock in them; instead, they second-guess themselves."

Trust your gut. There's a good chance it's right.