So you say it's your birthday?

Everyone's having a birthday this year, but some are more important than others. Here are some choices and opportunities that come with reaching a "milestone" age in 2006.

Age 50: You become eligible to make "catch-up," or extra, contributions to your IRA and 401(k), or similar retirement plan. This year, the 401(k) catch-up amount is $5,000 over the basic limit of $15,000, which brings the total contribution allowed to $20,000. For an IRA, the catch-up is $1,000 over the basic $4,000 contribution, for a total of $5,000.

Age 55: If you leave your job or retire, you may withdraw savings from your 401(k) without paying a 10 percent early withdrawal penalty. However, you will need to pay income tax, unless you roll the money into an IRA or another 401(k).

Age 59: You may withdraw money from a 401(k) or your IRA without paying the 10 percent penalty - regardless of whether or not you leave your job or retire. You'll have to pay income tax, unless you roll the money into an IRA or another 401(k).

Age 62: You're eligible to start receiving Social Security. However, you may want to consider waiting. The longer you wait (up until age 70), the higher your benefit will be. Another reason to delay is the "earnings test." If you receive Social Security while you're earning money from a job, your benefit will be reduced if your earnings exceed the annual minimum.

Age 65: You're now entitled to Medicare coverage. Take it, even if you don't plan to go on Social Security yet. "Medicare and You 2006" is a good, basic source of information (go to www.medicare.gov for a copy). If you want to retire before you turn 65, be sure to explore other options for health insurance because this expense could eat up a substantial portion of your retirement income.

Age 62 to 70: You can start collecting Social Security any time now, but the longer you wait, the larger your benefit will be. The size of your benefit will depend on the year you were born, which determines your "full retirement age," an arbitrary point when you will receive what Social Security calls your full benefit.

Age 70: Uncle Sam requires you to start withdrawing money from your 401(k) and Traditional IRA (but not a Roth IRA) in the form of a "required minimum distribution" (RMD). The exact amount you must withdraw, based on a formula pegged to your life expectancy, is subject to income taxes (ask your financial or tax advisor calculate your RMDs and potential tax consequences). Failure to take an RMD will result in a 50 percent tax penalty on the balance not withdrawn.

For more information, call me at 689-8704 or e-mail william.a. creekbaum@smithbarney.com.

• William Creekbaum, MBA, CFP, a Washoe Valley resident, is senior investment management consultant of SmithBarney, a financial services firm serving Northern Nevada at 6005 Plumas Street, Ste. 200 Reno, NV 89509.