Many Americans look forward to retirement, especially after a lifetime of hard work. But what happens when you retire and find that it's not exactly what you thought it would be? What if you're just not thrilled with your new lifestyle despite the fact that you initially thought you'd love it? If that's the case, you might consider returning to work, even after you've called it quits. Here are a few signs that this is the right move for you.

1. You're depleting your nest egg more rapidly than expected

Even seniors who enter retirement with a healthy level of savings sometimes come to find that their living costs are higher than expected, and as such, they're withdrawing more from savings than anticipated. Estimating your living costs in retirement can be tricky, especially since certain expenses, like healthcare and leisure, have a tendency to rise. But if you find that you're depleting your nest egg too quickly, returning to work is a good way to stop the bleeding.

Senior male with serious expression

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How do you know if you're putting yourself at risk of drawing down too much savings and eventually running out of money? As a general rule, you can expect to safely withdraw about 4% of your nest egg's value each year and have enough savings to last 30 years. Now there is some wiggle room with that 4% depending on your circumstances and investment mix, but if you find that it takes, say, 8% of your nest egg per year to cover your living costs, it's a sign that you don't have enough money saved and should therefore consider resuming your career to bring a paycheck back into your life.

2. You're lonely

If you retire at the same time as your spouse and friends, you may discover your social calendar is more than full. But if you're the sole retiree in your circle, or realize that the occasional company of others just isn't enough, that's reason to go back to work, especially if your office once served as a social outlet.

In a 2017 Rand Corp study, the one thing seniors missed the most about their pre-retirement lives was the camaraderie their former colleagues offered. So if you're longing for that company, going back to work is a good way to stave off feelings of loneliness.

3. You're bored

It's a frightening statistic that retirement increases the likelihood of suffering from clinical depression by 40%. But it also makes sense. If you're used to a career that keeps you busy, and go from that to days on end with nothing to do, you're apt to grow restless and start feeling worthless. So if you find that retirement is nothing more than one extended period of boredom, it pays to think about going back to work.

There are plenty of good reasons to resume a work schedule even after you've retired. That said, you don't necessarily need to return to your former career or employer. Retirement is a great time to start your own business, so if there's something you've always wanted to do, there's no reason not to pursue it later in life. In fact, seniors 65 and older are more likely to be self-employed than any other age group, which proves that retirement is actually the perfect time to venture out independently. And if doing so gives you the income, social interaction, and purpose you need to enjoy retirement to the fullest, the decision is pretty much a no-brainer.

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