Thinking About Retiring at 55? The Hidden Health Insurance Trap You Must Plan For.

Early retirement isn't an easy thing to pull off. But if you've built a lot of retirement savings, you may find that you're able to leave the workforce well ahead of your peers.

Now one thing you should know is that if you try to tap your IRA or 401(k) before age 59 1/2, you'll typically face an early withdrawal penalty of 10%. But there's an exception to that restriction.

Image source: Getty Images.

If you have a 401(k) and separate from your employer in the calendar year you turn 55 or later, you're typically allowed to take penalty-free withdrawals from that workplace plan only. This exemption does not apply to 401(k)s through former employers or IRAs.

As such, with enough savings, retiring at 55 may be doable. But if you're going to go that route, there's a big expense you'll need to plan for.

Don't let healthcare costs derail your early retirement plan

If you're used to getting health insurance through your employer, retiring at 55 might leave you paying for coverage on your own. That's because Medicare eligibility typically does not begin until age 65.

In other words, you could get stuck paying health insurance premiums for a whole decade if you leave your job at 55 and don't have a spouse with a workplace health plan you can join. And that cost could easily sink an otherwise solid retirement budget.

Now if you're wondering how much it costs to buy your own health coverage for 10 years, the answer is, there's no particularly easy way to tell. That's because insurance premiums can vary substantially based on factors such as your specific age, your prescription needs, your desire to retain access to specific in-network providers, and your geographic location.

But suffice it to say that if you end up having to cover the cost of health insurance premiums following an early retirement, that may end up being your single largest recurring expense (unless you happen to have an exorbitant mortgage to boot). So your best bet is to do your research before you leave your job at 55 and at least try to narrow a range of costs you might be looking at.

Also keep in mind that premiums and out-of-pocket costs often have an inverse relationship in the world of health insurance. The less you pay for one, the more you might pay for the other. So even if you're able to find a so-called low-cost plan, less expensive premiums may come at the expense of higher deductibles and copays.

Don't get caught off guard

A lot of people know to factor in Medicare costs once they retire. If you'll be leaving the labor force at 55, don't expect the cost of health insurance to mimic that of Medicare during that 10-year gap.

In reality, your costs could be a lot higher. The better you research and plan, the less surprised and stressed you're likely to be.

The Motley Fool has a disclosure policy.