The "Safe" Age to Claim Social Security Isn't What You Think. Here's Why.

Even if you manage to retire with decent savings, you might need your Social Security benefits to cover a good chunk of your retirement spending. So it's important to make sure you claim them strategically.

The earliest age you can sign up for Social Security is 62. But if you don't wait until full retirement age, those monthly benefits will be reduced. Full retirement age is 67 for anyone born in 1960 or later.

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There's also the option to delay your benefit claim past full retirement age. For each year you wait, until age 70, your Social Security benefits increase by 8%.

Some financial experts might tell you that 70 is the "safest" age to file for Social Security, since it guarantees the largest possible monthly payments. But following that advice could actually end up costing you.

Why waiting until 70 doesn't always pay

It's true that claiming Social Security at age 70 is guaranteed to give you larger benefits on a monthly basis. But it's not guaranteed to give you a larger total benefit on a lifetime basis. And that's where a lot of people go wrong.

Imagine this scenario. You file for Social Security at 70 and boost your $2,400 monthly benefit to $2,976. You've got an extra $576 a month coming your way, which gives you more spending power you appreciate having.

But what if you die at 77 years old? In that case, you're looking at a total of $249,984 in Social Security benefits in your lifetime. But had you filed at 67 in this scenario, you would've had $288,000 in Social Security by 77 instead. That's a $38,000 difference.

Of course, the numbers look much different if you live until age 87. In that case, filing at 70 gives you a lifetime total of $607,104 in Social Security, compared with a lifetime total of $576,000 by claiming benefits at 67. So in this situation, you're up $31,104 by filing at 70.

The problem, of course, is that when you're in your 60s and trying to decide when to claim Social Security, you don't know if you'll live until 77, versus 87, versus any other possible number. And if you delay your claim, you run the risk of shorting yourself on lifetime benefits, despite boosting your Social Security checks on a monthly basis.

Factors to consider when making your choice

Since seeing into the future isn't something anyone can do, your best bet when deciding whether 70 is a "safe" age to file for Social Security is to think about the pros and cons as well as your personal circumstances.

The pros are larger monthly checks in the near term and a potentially larger lifetime payout. If you're married, there's another possible perk -- larger survivor benefits for your spouse, assuming you're the higher earner in your household.

The cons, on the other hand, are potentially collecting a smaller lifetime Social Security check and having to wait longer to start getting your money. The latter could mean different things -- having to work longer, putting off travel or home improvements, or delaying another milestone requiring an influx of money.

You should think about your health when deciding whether delaying Social Security until 70 is a good idea. If you're already grappling with multiple chronic issues in your 60s, you not want to hold off. If your health is outstanding, that's not guaranteed to last -- but it's a sign that delaying could make sense.

Also look at your retirement savings. Will you need larger Social Security checks to cover your basic needs? If so, delaying could be a no-brainer.

But if you have $3 million sitting in your IRA, Social Security may be more like backup money, playing second fiddle to your very impressive nest egg. In that case, delaying your claim until 70 may only have limited upside, whereas getting the money sooner could make other elements of your life easier.

All told, it's not an easy decision to make. And you may, after running the numbers and thinking things through, come to the conclusion that claiming Social Security at 70 is your optimal move. Just make sure you arrive at that decision on your own, as opposed to opting for what many might sell as the "safe" filing choice.

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