Many workers look forward to retirement and the chance to get a break from the daily grind. Unfortunately, the harsh realities of retirement tend to sneak up on seniors and cause them to wind up less than satisfied.

Case in point: An estimated 26% of seniors who have been retired for 10 years or more, along with 27% of recent retirees, say their lives are worse at present than they were during their working years, according to the Nationwide Retirement Institute. Here are three reasons why you might end up hating retirement -- and what you can do about them.

1. You don't have enough income to live comfortably

As a general rule, you can expect to need about 80% of your pre-retirement income to live comfortably as a senior. Now there's some wiggle room with this formula, which means that if you're willing to downsize your living space or relocate to a less expensive area of the country, you might manage to get by on more like 65% or 70% of your former earnings. But for the most part, you should plan on that 80% income replacement rate.

Senior woman wiping away tears

Image source: Getty Images.

The good news is that Social Security will cover some of your bills as a senior -- but it'll be on you to come up with the rest. Therefore, take a look at your savings and see if they're adequate before moving forward with retirement. If you end your career earning $80,000 a year and expect to collect $2,000 a month in Social Security, you'll need another $3,333 a month to have a total annual retirement income of $64,000, which is 80% of $80,000. That amounts to about $40,000 a year from savings.

Now as a general rule, you can expect to withdraw about 4% of your nest egg's value each year and not have to worry about running out of money in retirement. Therefore, if you think you'll need $40,000 a year from savings, you'll want to retire with about $1 million. Allow yourself to leave the workforce with considerably less, and you'll risk struggling financially later in life.

2. You're plagued by medical bills

Healthcare is a major burden for seniors, so much so that the typical 65-year-old man today who lives an average lifespan is expected to spend $189,687 on it throughout retirement, while the typical 65-year-old woman will spend $214,565. And if you enter retirement with known health issues, or problems develop once you stop working, it can make for an expensive -- and stressful -- existence.

Thankfully, there are steps you can take to lower your healthcare spending in retirement. First, be smart about Medicare. Original Medicare won't cover many common expenses, like dental and vision care, so it might pay to sign up for a Medicare Advantage plan instead. Shopping around for the right drug plan will also help keep your costs down, so plan to evaluate your prescription needs on a yearly basis and choose plans that offer the best coverage. Keep in mind that Medicare Advantage will serve as your drug plan as well if you sign up for it.

Of course, it's always a good idea to get ahead of health issues before they escalate to keep their associated costs down. And getting regular checkups is a good way to go about that. In fact, under Medicare, you're entitled to a free wellness visit each year, so plan to use it -- it'll save you money and stress.

But most importantly, go into retirement with adequate savings. This way, if health issues do end up costing more than expected, you'll have a well to tap.

3. You're bored

There's a reason retirement increases the likelihood of suffering from clinical depression by 40%: Having too much free time on your hands can easily lead to feelings of boredom and worthlessness. And if you don't have enough savings to entertain yourself adequately, you could wind up miserable in a matter of months.

That's why it's crucial to think about how you'll spend your days in retirement before pulling the trigger, and then make sure your savings are such that they'll support the activities you have planned. For example, you might intend to take classes at a community college or work on improving your golf swing, but if you can't afford the cost of tuition or a country club membership, you'll need a less expensive backup plan (either that, or more savings).

If you know you're coming into retirement with limited money to spend on leisure, be sure to come up with a list of options for free or low-cost entertainment before leaving your career behind. Outdoor activities like hiking and backpacking are generally free, and often, you can visit museums as a senior at a fraction of their normal entry fee. Either way, make sure you'll really have enough to do with your time before moving forward with retirement, because you might find that it makes more sense to work an extra year or two, save up some additional money, and then retire at a point where you can do the things you want to do.

You deserve to enjoy retirement to the fullest. Save appropriately, plan for medical expenses, and figure out how you'll spend your days, and with any luck, you'll do just that.

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