There are dozens of factors to consider before you retire. Do you have enough saved to cover all your daily expenses? How much will you depend on Social Security? How do you plan to spend all your free time?

One factor in particular, though, can't be overlooked: Healthcare costs.

When you're relatively young and just starting retirement, healthcare costs are probably the least of your worries. But these problems can crop up sooner than you'd think, and your budget should be prepared for them.

A whopping 90% of recent retirees say they've experienced health issues sooner than they expected, according to a survey from the Nationwide Retirement Institute, and of those respondents, 60% said these problems arose at least five years earlier than they anticipated.

If you're not preparing for them, these costs can take a huge bite out of your retirement savings. Especially if you weren't planning on having to worry about significant expenses until later in life, earlier-than-expected healthcare costs can throw off your entire retirement budget. Fortunately, there are a few ways to plan ahead so you're not taken by surprise.

Money and pills on a scale

Image source: Getty Images

Expect the unexpected

Nobody can predict exactly what obstacles they'll face in retirement, but by having a good idea of potential issues that can arise, it's easier to plan for them.

First, be aware of what Medicare will and will not cover in retirement. Nearly three-quarters of Americans admit they don't fully understand how Medicare works, according to a separate survey from the Nationwide Retirement Institute, and 53% mistakenly believe that coverage is free for retirees.

Even with Medicare coverage, you're still responsible for all premiums, deductibles, and coinsurance. Original Medicare (or Parts A and B) also doesn't cover most routine care -- such as eye exams and dental care -- and you'll need to enroll in a separate Part D plan for prescription drug coverage. You can opt for a Medicare Advantage plan, which offers similar coverage to what you likely received through your employer, but prices vary by location and are often more expensive than Original Medicare.

Long-term care is another expense that, if you're not prepared for it, could break the bank. Nearly 70% of today's 65-year-olds will need long-term care at some point in their lives, according to the U.S. Department of Health and Human Services, and this expense typically isn't covered by Medicare.

As one might expect, long-term care isn't cheap either; the average semi-private room in a nursing home costs around $6,800 per month, according to the Department of Health and Human Services. Considering the fact that 20% of those who need long-term care need it for at least five years, that $6,800 per month can amount to more than $400,000 in that time period. And because Medicare normally won't cover nursing home care, that money will need to come from your pocket.

Preparing for big-ticket costs

While healthcare costs can potentially bust your budget wide open if you're not expecting them, there are a few things you can do to prepare for them well in advance so you're not caught off guard.

If you're eligible to open a health savings account (HSA), that's a good place to start. HSAs are available to those with high-deductible healthcare plans, meaning you have a deductible of at least $1,350 (or $2,700 if you have coverage for the entire family) and a maximum out-of-pocket limit of $6,750 (or $13,500 for families).

An HSA is essentially a separate retirement fund just for healthcare costs, and it has two main tax advantages. First, contributions are tax-deductible upfront, and second, withdrawals are tax-free if the money is used for qualified medical expenses. An HSA is similar to a flexible spending account, except you can stash your money in your HSA for years (there's no "use it or lose it" policy like with most flexible spending accounts).

Also, HSAs are similar to traditional retirement funds in that you invest your money and let it grow over time. For 2019, you can contribute up to $3,500 per year to your HSA (or $7,000 for families). By investing early and letting your money grow for a few decades, you can rack up hundreds of thousands of dollars in savings that can go toward lofty healthcare costs.

Long-term care insurance is another way to limit sky-high expenses. This type of insurance is notoriously expensive (the average 55-year-old couple can expect to spend around $2,500 per year on premiums, according to the American Association for Long-Term Care Insurance), but a few thousand dollars per year is preferable to hundreds of thousands of dollars if you have to pay for long-term care out-of-pocket.

The key to getting the best long-term care insurance rates is to enroll sooner rather than later. If you don't sign up until you're in your 60s, you'll either be slapped with steep rates or be denied coverage altogether.

No retiree can completely avoid healthcare costs, but if you're not prepared for them, they can potentially wreck your retirement plans. By studying up on what you can expect and preparing accordingly, though, you can protect your savings and live a more enjoyable retirement.