Don't wait to enjoy these moments if you don't' have to. Photo: Keoni Cabral, via Flickr.

Social Security benefits are the most important -- and plentiful -- source of income for today's retirees. According to an October 2015 report from the Social Security Administration, benefits from the program "represent about 39% of the income of the elderly." 

That's an astounding percentage. It underscores how important the timing of claiming benefits can be. For those nearing retirement, the "full retirement age" is 66. But you can claim as early as 62 years old, and as late as 70. These choices will affect the actual dollar amount you get every month.

Here's how that breaks down, based on your "full" Social Security benefits.

Age

% of Full Benefits

62

75%

63

80%

64

86.7%

65

93.3%

66

100%

67

108%

68

116%

69

124%

70

132%

Source: Social Security Administration. Assumes you file for benefits just after each of these milestone birthdays.

Looking at this, it would seem absolutely silly not to wait until age 70 to claim your Social Security. Who wouldn't want more money each month? And in a lot of cases, you'd be right: waiting makes sense.

But there are a handful of circumstances where this just doesn't add up. Consider some of the awful reasons given for planning to wait until 70:

1) You'll "file-and-suspend"
Technically, this isn't an "awful reason" quite yet. For a long time, "file-and-suspend" was a popular loophole. If the breadwinning spouse filed for Social Security at 66, the other spouse could then start collecting maximum spousal benefits. The breadwinning spouse would then turn around and suspend their benefits, waiting until age 70 to start collecting.

However, the window for taking advantage of this loophole is closing fast. As part of the budget deal reached by Congress last year, file-and-suspend will no longer be a viable strategy as of May 1st. Either your spouse will receive no benefits, or you'll be unable to "suspend" and wait until age 70.

2) You want more to pay for medical expenses
It's no secret that healthcare costs have skyrocketed over the last two decades. On the surface, it might make sense to wait until 70 to file for Social Security; the added income will help offset the costs, and mean you'll be less of a burden to your children, grandchildren, spouse, or whoever else might need to help you in your old age.

But this reasoning completely ignores two crucial factors. The first is Medicare. You can file for Medicare at age 65. If you're already receiving Social Security benefits at this age, your enrollment is automatic; but that's not the case if you haven't enrolled. And every year that you wait to file for Medicare can cost you -- big time.

For every 12 months that you could have been on Medicare Part B, for instance, but weren't, your eventual premiums will increase by 10%. Wait all the way until you are 70 and your monthly Medicare Part B premiums will be 50% higher -- and that change will be permanent.

Of course, you can avoid this by simply filing for Medicare at 65 and waiting to file for Social Security. But that brings us to our second point: if your health is a major concern, the fact of the matter is that your life span might not be as long as your peers'.

Filing for Social Security earlier can allow you to live better duringthose remaining years -- traveling, seeing family and friends, or pursuing a passion. Which brings us to our last point...

3) You want, but don't need, all that extra money
Let's pause and think for a moment about why people enjoy retirement. First and foremost is the freedom that it provides. You have an opportunity to give your body and your mind a rest, and only focus on the things that really matter to you.

While that may sound a little rosy, it turns out that these things actually do make a difference. A study by T.Rowe Price found that 89% of retirees were somewhat or very satisfied with retirement. Not only that, but, "Nearly three years into retirement, retirees report living on 66% of their pre-retirement income on average." In fact, "most (65%) like not spending as much and see it as a new found freedom from 'keeping up with the Joneses.'"

I can't emphasize these trends enough. While it might make sense to try and stockpile as much cash for retirement as you can, the fact of the matter is that many don't need it to enjoy retirement. In the end, by waiting until 70 when you don't absolutely need to, all you're doing is cutting years off an enjoyable retirement.