It's in some people's best interest to take Social Security as early as possible even though it could reduce their benefits by as much as 25%. But there are three circumstances in which it's best to wait until age 66 or later.

The first is if you continue working past the age of 62. If you do, and you earn above a predetermined threshold (currently $15,480 per year), then your Social Security benefits are temporarily reduced by $1 for every $2 in wages in excess of the limit -- this stops once you reach full retirement at 66.

The second is if you're optimistic about your longevity. If you're healthy and legitimately expect to live longer than the average American, then it would behoove you, at least financially, to wait until full retirement before receiving benefits.

And finally, if you have a spouse or other dependents that will receive survivors' benefits, it's often in their best interest if you hold out as long as possible. This is because the larger benefits associated with waiting will accrue to them even after you're gone.

The net result, as Motley Fool contributor John Maxfield concludes in the video below, is that you should be particularly attuned to these exceptions when you're deciding whether or not to apply for Social Security benefits prior to your 66th birthday.

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