Here's Why Planning to Claim Social Security at 70 Could Be Risky
One nice thing about Social Security is that you get a choice when it comes to claiming benefits. You can sign up at any age between 62 and 70, but you won't get your full monthly benefit based on your personal earnings history until full retirement age (FRA) arrives. FRA is 67 if you were born in 1960 or later.
You can also delay your Social Security filing past FRA for a higher monthly benefit. There's no "final age" by which to sign up, so you can file as late as you want.
But it doesn't make sense to delay your claim past age 70 because you won't be rewarded financially for filing past that point. As such, 70 is generally referred to as the latest age to claim Social Security, even though you can technically sign up later.
Source Fool.com
