Until a few years ago, the Social Security Administration (SSA) mailed periodic estimates of retirement benefits to all workers. Not anymore. But you still can get a good idea of what your monthly benefit amount will be by using the SSA's Retirement Estimator at www.ssa.gov/retire/estimator.html.

Keep in mind that this is just an estimate based on your earnings history. It isn't written in stone. Also, Social Security rules may change in the future.

You can use the Retirement Estimator if you have enough Social Security credits to qualify for benefits and you're not (1) currently receiving benefits on your own Social Security record; or (2) waiting for a government decision about benefits or Medicare; or (3) age 62 or older and receiving benefits on another Social Security record; or (4) eligible for a pension based on work not covered by Social Security.

Note that your actual retirement benefits can differ from the estimate for several reasons:

• Your earnings may go up or down in the future.
• After benefits begin, they may be adjusted for cost-of-living increases.
• Estimated benefits are based on current law.
• Your benefit amount may be affected by military service, railroad employment, or pensions earned through work on which you did not pay Social Security tax.

Some other online estimators address those issues. But even if you don't get the estimate of your future benefits right to the penny, a ballpark figure can help in your overall retirement planning.