No time for vacation? Apparently, there is — you’re just not tapping into all of it.

According to Project: Time Off, which annually releases research conducted by the US Travel Association, last year American workers used on average 16.2 vacation days, and more than half of survey participants admitted to leaving unused days on the table.

“Many employees across America don’t receive paid leave days as part of their jobs, yet there are also millions of workers who are taking significantly less leave than their [employers are] giving them, failing to take all of the days they are owed,” explains Amantha Imber, psychologist and author of “The Innovation Formula: The 14 Science-Based Keys for Creating a Culture Where Innovation Thrives.”

Here are the most common excuses employees use not to take time off — and the reasons why they should.

No one else can do your job

Reality check: You’re not as irreplaceable as you think. Imber indicates that with the proper planning, it should be no problem to train a co-worker to temporarily back you up while you’re out of the office.

“Your boss will love this, because you just up-skilled someone else who can now pick up the load if you are on vacation,” says Imber. So not only are you proving to your boss that you can delegate and mentor other employees, you won’t have to feel guilty about taking time off in the future because now you know someone will have your back.

You’ll return to a pile of work

Sure, your personal inbox may be bursting at the seams upon your return, but if you’ve properly trained a co-worker to cover for you while you’re gone then you should have little to address.

Imber explains: “If you are lucky enough to have hardworking colleagues, you might even come back to less work because [they] have gotten through it all in your absence.”

You’re too busy to take time off

Your workload is never-ending, that’s a given. “After all, you are the self-proclaimed busiest person on the planet!” says work-life-balance expert Samantha Ettus.

Ettus, author of the upcoming book “The Pie Life” (out Sept. 27), says being “too busy” usually means you’re running away from an unhappy personal life. So assess your relationships with friends, family and partners to see if there are areas that need improvement. “A fulfilling life involves a thriving professional and personal life,” she adds. “One without the other is like peanut butter without the jelly. It never tastes quite right.”

You want to show dedication to your job

If it’s loyalty you want to prove, Imber says the best way to do that is “by staying with your company for a few years — not by never taking a holiday.”

Also, if you never take a break and remain on the hamster wheel indefinitely, you’ll burn out and be of no use to anyone — see how long you stay employed then. “Do yourself, and your company, a favor,” says Imber. “Take time off so you can stay fresh and do your best work when you are at work.”

And while some people worry that their bosses will realize that they’re replaceable while they’re gone, in reality it’s unlikely you’ll get sacked just because someone filled in for you for a week or two.

Traveling is too expensive

Karen Schaler, creator and host of “Travel Therapy TV,” says that’s trash talk, regardless of the size of your bank account. “Be creative [and] think outside the box, like doing a home swap with friends,” she says. Research vacation deals online and make the investment in yourself without breaking the bank. “You can find huge savings if you plan a vacation off the beaten path and go off-season.”

But you’re the boss, you can’t leave!

When you’re the boss, you’re setting a precedent for your employees — you simply have to take time off and delegate, no questions asked, says Ettus.

“When you don’t take vacations, your employees will be less apt to take their vacations,” she says. “The entire culture becomes miserable.”