Over the years, your traditional IRA and 401(k) helped you reach retirement savings goals faster by allowing earnings to benefit from tax-deferred growth.

But eventually, Uncle Sam wants his share.

Regardless of financial need, the Internal Revenue Service generally requires owners of traditional IRAs, 401(k) plans, simplified employee pensions, or SEPs, and SIMPLE accounts to begin taking minimum distributions (and paying the resulting tax) by April 1 of the year after they reach age 70½.

Each year thereafter, your required minimum distribution, or RMD, is due by Dec. 31.

(Note that if you wait until April 1 to take your initial distribution for the previous year, you’ll still be required to take a distribution by Dec. 31 for the current year, which results in a double tax bill. Also, note that Congress suspended RMDs for the 2009 tax year only due to the recent stock market decline. RMDs must be taken in 2010.)

Even if you began receiving distributions before age 70½, you must calculate and receive the RMD by the required beginning date.

Determining how much you need to take is not necessarily difficult, but it does demand accuracy.

Failure to take those distributions, or take a large enough amount, results in a 50 percent excise tax on the amount not distributed.

“Some people are not even aware that they have to begin distributions at 70½ and the penalty is very severe,” says Bill Bengen, a Certified Financial Planner and author of “Conserving Client Portfolios During Retirement.”

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