When should you retire?

Retirement used to be referred to as "a three-legged stool" that rested on pension checks, personal savings and Social Security benefits. 

That stool is a lot wobblier today, says Joe Buhrmann, a senior financial planning consultant with Fidelity's eMoney Advisor. Social Security is threatened with insolvency, while pensions are a thing of the past for most Americans.

The lion's share of retirement income now comes from personal savings. 

How do you know if you've saved up enough for your golden years? CNBC Select chatted with retirement experts about recognizing the signs that you're ready to retire.

Heading into retirement with a mortgage, car payments or even student loans can mean your financial future is less stable. That's especially true of high-interest consumer debt, like a gigantic credit card balance, Buhrmann said.

One way to eliminate out-of-control debt is with a debt consolidation loan, which gets you a lower interest rate and streamlines your payments into one place. SoFi offers consolidation loans with no origination fees, late fees or early payoff penalties. Upstart is a good option if you don't have a robust credit history.

Figuring out how much money you need before you can quit working is a job in and of itself.

Some experts say that you should save at least 10 times your annual salary socked away by the time you're 67. Others point to the 4% rule, which says you should be able to comfortably live off of about 4% of your investments in each year of retirement, thus allowing you to cover expenses for about 30 years.

The 4% rule is a good indicator if you plan on spending the same amount in retirement as you do now, says Jackie Cummings Koski, a financial consultant who retired at 49. But Koski recommends building an estimated expense budget to get a more accurate picture.

"One of the first questions would be, 'What does retirement look like for you?'" Koski said. "For some people, that might mean all they want to do is play with their grandkids and travel."

Frequent traveling means having to save a lot more money or risk outliving your savings.

Once you get an estimated retirement budget, multiply it by 25 to get a fairly accurate amount that will see you through retirement. If you expect to spend $40,000 a year, for example, you need $1 million ($40,000 x 25) to retire comfortably. 

One of the biggest mistakes you can make in retirement planning is not having an emergency fund. Your assets aren't as liquid in retirement — you can't just go to the ATM and withdraw cash when your money is invested in the market.

A high-yield savings account (HYSA), lets your money earn robust interest while still enjoying FDIC protection. Marcus by Goldman Sachs has a fee-free HYSA with no limit on how much money you can withdraw. (There is a limit of six withdrawals and transfers per monthly statement period, however.)

The Ally Bank Savings Account also has a solid annual percentage yield (APY) and comes with an ATM card with access to over 43,000 free Allpoint^® ATMs. You can organize deposits into "buckets" within the same account, so save for different occasions. 

Your emergency fund should be easily accessible and shielded from the ups and downs of the stock market.

"You don't want to say 'Honey, you can't have that heart surgery because our accounts are down 20%,'" Buhrmann said. "You want that to be safe and secure."

Putting all your retirement eggs in one basket isn't a good idea. Mitigate your financial risk by spreading your savings and investments across multiple streams of future income. 

"​​You build wealth through concentration. You protect wealth through diversification," says Scott Bishop, a Houston-based certified financial planner who specializes in retirement planning.

If you're trying to build momentum early in your retirement savings journey, Bishop said its smart to invest in securities that may be riskier but have the potential for higher returns, like stocks. If you're closer to retirement, it might make sense to invest in safer but slower-growing accounts, he added, like certificates of deposit or money markets. 

Robo-advisors can help align your retirement portfolio with your risk tolerance, time horizon and financial goals, while allowing you to remain hands-off. Both Betterment and Wealthfront automatically rebalance your portfolio over time to account for changes in your time horizon and needs.

Working with a financial planner is another way to help you figure out how to best diversify your retirement portfolio, relieving some of the stress that accompanies retirement saving.

Still, make sure you have cash reserves on hand for when the markets curve downward. This way, you can allow your investments to rebound, instead of tapping them to cover expenses.

Even if you have healthy investments or a pension, it's important to know how much you can expect in your monthly Social Security check. To get a good idea, log onto the Social Security Administration (SSA) website and review your projected benefits after retirement.  

You can start drawing Social Security at 62, but waiting at least until your full retirement age can mean bigger payments. According to the SSA, benefits increase by up to 8% each year you delay.

If you wait until 70 to start collecting, you can receive delayed retirement credits for each month you delay. (The benefit increase stops when you reach age 70.)

"I've had clients that have made those decisions and regret that now," Bishop said. "They're getting $1,500 or $1,600 a month from Social Security, where they could have had $2,400 or $2,500 a month if they waited a few years."

Health costs rise exponentially in retirement, right when your employer-backed health insurance ends.

If you are enrolled in a qualifying high-deductible health plan, Buhrmann recommends planning ahead and opening a health savings account (HSA) while you're still working. The government doesn't tax any earnings in an HSA and the withdrawals are also tax-free if you use them for qualified medical expenses like surgery, tests or prescriptions.

You can't contribute to an HSA once you enroll in Medicare, but you can continue to make withdrawals from the account to help with medical bills. You may be able to open an HSA account at work, through financial institutions like Bank of America or with providers like Lively.

Long-term care insurance covers support services like at-home care, physical therapy, assisted living and nursing facilities. Since it's a lot harder to get approved with a preexisting health condition, experts recommend buying a policy in your mid-50s, when you're still relatively healthy.

"Just like you shouldn't try to buy home insurance when your house is on fire, the week before grandad goes into the nursing home is not the time to apply for a long-term care policy," Buhrmann said.

New York Life is one of CNBC's top picks for long-term care insurance and it's one of the few providers that still offers a stand-alone policy. The Secure Care plan can be used to pay for care provided by family members and couples that purchase a joint policy can earn a discount of up to 25%.

MassMutual's hybrid policies combine life insurance with a long-term care benefit. Both the CareChoice One and CareChoice Select plans are eligible for annual dividends.

At CNBC Select, we work with experts who have specialized knowledge and authority based on relevant training and/or experience. For this story, we interviewed Joe Buhrmann, a CFP and senior financial planning consultant at Fidelity's eMoney Advisor, and Jackie Cummings Koski, a Cincinnati-based financial consultant and author of F.I.R.E. for Dummies and co-host of the Catching Up to FI podcast. We also spoke with Scott Bishop, partner and managing director of Presidio Wealth Partners.

At CNBC Select, our mission is to provide our readers with high-quality service journalism and comprehensive consumer advice so they can make informed decisions with their money. Every personal finance is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of financial products. While CNBC Select earns a commission from affiliate partners on many offers and links, we create all our content without input from our commercial team or any outside third parties, and we pride ourselves on our journalistic standards and ethics.

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