Retirement Planning: 5 Essential Deadlines You Shouldn't Miss

Some deadlines come and go without much notice. But other deadlines are critical to your financial well-being. We've got five retirement planning reminders you shouldn't miss.

Pull out your pocket calendar and get ready to scribble in some notes.

IRA contributions
It's a pretty safe bet that you know this one, but it's always good to put a reminder in your planner or smartphone: IRA contributions for the prior calendar year have to be made before the tax filing deadline of April 15.

You can put up to $5,500 of your earned income into an IRA for 2013. And the amount will remain the same for 2014 contributions as well.

Catch-up contributions to your retirement account
If you are 50 or over and want to make up for lost time with your retirement savings, here's a deadline you want to circle on the calendar: Dec. 31.

That's the deadline for making a catch-up contribution to your 401(k) and most other employer-sponsored retirement plans. The maximum amount you can kick in to the kitty varies by the account, but for your 401(k) you can add $5,500 (for 2013 and 2014), and for your IRA you can deposit another $1,000.

It's really rare, but some employer-sponsored retirement plan years may end at a date other than Dec. 31. Check with HR to be sure. And some employers will allow after-tax catch-up contributions. Be sure to ask.

And just to be totally accurate: You can make your IRA catch-up contribution by the tax deadline of April 15.

Required minimum distributions
This is a giant yellow "Caution" sign on the side of Retirement Road. You can't miss this one! Required minimum distributions must be taken from all qualified retirement plans: 401(k)s, IRAs, SEPs, and all the rest.

You have to withdraw a minimum amount, as mandated by IRS tables, by April 1 of the year following the year you turn 70 1/2. Isn't the government crazy specific? No matter how wacky the details, this is one rule you don't want to ignore. Failing to withdraw the necessary amount on time triggers a 50% penalty!

Full retirement age
This is an important date for those who continue to work after their full retirement age, as defined by Social Security. Before this age, which varies from 65 to age 67 depending on when you were born, if you draw Social Security benefits while still working, they are reduced by $1 for every $2 you earn over $15,480 (for 2014). Even in the months before reaching your full retirement age, your benefits are reduced by a certain amount over an earnings cap.

But the good news for working "retirees" is, after you reach that magical month of your full retirement age, you receive full Social Security benefits regardless of the income you receive.

This can be a real boost for those who have struggled to save enough for retirement. Generating an income, without an earnings limit reducing benefits, and receiving full Social Security payments can really help close the income gap for late savers.

NerdWallet Inside Tip: You don't permanently lose Social Security benefits that are withheld because of an earnings cap. They are deferred until you reach your full retirement age, at which time your benefits are recalculated. In fact, the more you earn, the more your Social Security benefits grow, because they are calculated based on your top 35 years of income.

Medicare
This one is easy: Sign up for Medicare when you're 65, right? Actually, that was a trick question. The mavens of Medicare actually want you to enroll three months before your 65th birthday, even if you plan on delaying benefits because you're still working.

You can sign up online, and they say it takes only 10 minutes. Of course, they said that about Obamacare, too, didn't they?

There you have it. The little-string-on-your-finger reminders for retirement planning.

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