The reason is simple. Eligibility for Social Security benefits starts at age 62. But full retirement age, as viewed by the government, ranges from age 65 to 67, depending on your year of birth. And if you start taking benefits before your full retirement age, your monthly check will be reduced.
For illustration purposes: Assume your full retirement age is 66, at which point you're due a monthly benefit of $1,000. If you choose to start receiving checks at age 62, your monthly payment will be $750, a 25 percent reduction. If you wait until age 70, your benefit will be $1,320—132 percent of that $1,000. And if, say, that $1,000 were $2,000, waiting until age 70 would mean $2,640.
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"There can be a huge difference," said Mike Prendergast, a certified financial planner with Altfest Personal Wealth Management. "And remember: You get cost-of-living increases, so delaying taking benefits until age 70 means those increases are based on a bigger monthly payout."
Of course, there are valid reasons to start taking money before your full retirement age. If you cannot cover your daily living expenses, for instance, taking benefits early not only makes sense but can be necessary.