If you want to get the biggest Social Security check possible, you'll likely have to wait until you turn 70 years old. The program rewards participants who wait to start collecting their benefits by offering them up to 8% for each year they delay past their full retirement age. Benefits top out at 70, and more often than not, waiting until that age to claim maximizes someone's lifetime income from Social Security.

But delaying benefits until 70 comes with some serious costs too. And sometimes, it doesn't make sense to wait that long at all. Here's the unfortunate truth about claiming Social Security at age 70.

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You're taking a risk

Though the data says delaying until 70 is the best choice on average, not everyone is going to maximize their lifetime Social Security income by waiting. Some people will live long enough to more than make up for the benefits they gave up in their 60s, and some won't. Unfortunately, there's no way to know which group you'll fall into.

But you can make a good guess.

If you've taken care of your health, have no concerning family history, and your doctors consistently tell you things are looking great, your best bet is to wait. But if you're in poor health or have a family history of premature death, you may want to consider claiming earlier. That may give you the cash you need to manage your health issues in the present so you can live a more enjoyable life.

You might have already maxed out your benefit

Not everyone maximizes their monthly benefit by waiting until age 70.

If you were the lower-earning spouse and you plan to take spousal benefits, you may want to claim your benefits once you reach full retirement age since that's when your benefits max out. You may also receive the full spousal benefit earlier if you're caring for a qualifying child of your spouse.

Spousal benefit recipients get up to one-half the benefit their partner is entitled to at full retirement age. If you earned far less than your spouse, that could be a bigger benefit than you'd receive based on your own earnings record, even if you waited until age 70.

There is a catch, though: To receive spousal benefits, your spouse must have already applied for Social Security benefits too.

Even if your spouse is still waiting to claim benefits, it often makes sense to claim your own benefit at full retirement age and then switch to your spousal benefit later. That should maximize your lifetime income from Social Security.

You'll have to pay for Medicare out-of-pocket

If you're no longer working and receiving employer-sponsored health insurance, you'll need to sign up for Medicare at age 65.

Most Medicare participants automatically enroll in the government program upon reaching age 65. That's because they've already signed up for Social Security. The government also automatically deducts Medicare Part B premiums from their Social Security check.

But since you won't be collecting Social Security at age 65, you'll have to enroll manually. What's more, you'll need to find the money in your budget to pay your premiums. Medicare Part B premiums start at $174.70 per month. That number will climb if you have an adjusted gross income above $103,000 (or $206,000 for a married couple).

Those premiums can be a big drag on your monthly retirement budget if you're not prepared to pay them. Make sure you plan for that monthly expense if you're delaying your Social Security benefits beyond age 65.