Retirement is something many workers dream about for decades. And for some it can't come soon enough -- half of American adults say they would like to retire by age 60, a survey from the Harris Poll and TD Ameritrade found.

However, not everyone is ready to retire, no matter how prepared they think they are. The median amount baby boomers have saved for retirement is just $152,000, according to a report from the Transamerica Center for Retirement Studies. If you're facing a savings shortage, there's a good chance you'll run out of money in retirement. In fact, the average American is expected to outlive their savings by eight to 10 years, a study from the World Economic Forum found.

Retirement takes a lot of planning, and choosing when to retire is a decision that shouldn't be made lightly. Before you leave your job for good, make sure you've considered these factors to ensure you're really ready to retire.

Mature couple toasting champagne

Image source: Getty Images.

1. You have a withdrawal plan

You've likely spent decades saving for retirement, so the last thing you want is to blow through your money by spending too much too soon. While it's tempting to splurge the first few years after you retire, and check off all the expensive to-dos on your bucket list, you'll need to pace yourself if you want your money to last the rest of your life.

Before you retire, create a withdrawal plan so you know how much you can safely withdraw from your savings each year. The 4% rule is a common way to estimate how much you can spend each year, and it states that if you withdraw 4% of your savings during the first year of retirement and then adjust that number each subsequent year to account for inflation, your savings should last roughly 30 years. So, for instance, if you have $500,000 stashed in your retirement fund, that means you can withdraw $20,000 the first year of retirement.

Keep in mind you'll also have Social Security benefits to help supplement your retirement income, but the average beneficiary receives just $1,471 per month, or approximately $17,600 per year. You likely won't be able to survive on your benefits alone, so you'll need to have some personal savings to fall back on.

The 4% rule isn't the only way to gauge how much you should be withdrawing each year, and sometimes it's best to consult with a financial advisor to see how much you can safely spend each year. No matter how you come up with your plan, it's crucial to have some type of withdrawal strategy in place before you retire.

2. You've thought about how you'll cover healthcare costs

Healthcare costs are one of the most significant expenses you'll face in retirement. Even if you're enrolled in Medicare, you'll still need to pay all premiums, deductibles, copays, and coinsurance. In addition, if you opt for Original Medicare (or Parts A and B), you'll also be responsible for the costs of routine care (such as dental and vision) because Original Medicare doesn't cover these expenses.

You can instead enroll in a Medicare Advantage Plan, which offers coverage that's likely similar to what you have through your employer. Although the coverage is more expansive, these types of plans are also more costly. Advantage plans are offered through Medicare-approved third-party providers, so prices vary depending on the provider and your location.

Long-term care is another expense you'll likely face in retirement, and it comes with a hefty price tag. The average semiprivate room in a nursing home costs around $6,844 per month, according to the U.S. Department of Health and Human Services -- that's approximately $82,000 per year. Around 70% of retirees will need long-term care at some point, and Medicare also doesn't cover this expense.

Healthcare costs can be unpredictable, which makes them difficult to plan for. Even if you're in excellent health and have health insurance, an accident or sudden illness can quickly drain your savings. A health savings account (HSA) is one way you can prepare for these costs. HSAs allow you to invest tax-deductible dollars, let your savings grow over time, and then withdraw your money tax-free as long as it goes toward qualifying medical expenses. The only caveat is that in order to open an HSA, you need to be enrolled in a high-deductible healthcare plan (meaning you have a deductible of at least $1,350 for individuals, or $2,700 for families).

Long-term care insurance can also help cover some of the costs you'll likely face in retirement, but this type of insurance isn't cheap -- especially as you get older. The average 55-year-old couple can expect to pay roughly $2,500 per year in premiums, according to the American Association for Long-Term Care Insurance, and the older you are when you enroll, the more you'll pay. But if you're going to be facing $82,000-per-year nursing home costs, insurance may be well worth the cost.

3. You've decided when you're going to claim Social Security benefits

The age at which you start claiming your benefits will affect how much you receive each month for the rest of your life. You can file for benefits as early as age 62, but if you do, your checks may be reduced by up to 30%. The only way to receive the full amount you're theoretically entitled to each month is to claim at your full retirement age (FRA), yet two-thirds of Americans don't know what their FRA is, according to a survey from Nationwide.

You can also boost your benefit amount by waiting until after your FRA to claim (up until age 70). If your FRA is 67 years old and you wait to claim until age 70, you'll receive a 24% bonus on top of your full benefit amount each month.

Choosing what age to start claiming benefits is a personal decision, and there's no one-size-fits-all approach. Sometimes it's best to claim as soon as you can, especially if you have reason to believe you may not spend many years in retirement. On the flip side, if you expect to spend several decades in retirement, it might be a good idea to hold off on benefits so you can receive those bigger checks for the rest of your life. Regardless of what age you claim, make sure there's a strategy behind your choice. It's difficult and sometimes impossible to reverse your decision once you start claiming your benefits, so choose wisely before you claim.

Retirement is a major milestone in life, and the decisions it involves shouldn't be rushed. If you retire before you're ready, you're more likely to struggle financially. But by waiting until you're fully prepared, you'll set yourself up for success in the decades to come.