Social Security's estimate has faults

The Social Security Administration will happily forecast your future monthly retirement check. Trouble is, it's often off the mark.

You can find your estimate online by creating a "My Social Security" account at the Social Security Administration's site, or you can call 800772-1213 to request a paper version.

Social Security projects how much you'll receive if you start benefits at the earliest age, 62, as well as what you will get if you start instead at your full retirement age — currently 66 and rising to 67 for people born in 1960 or later — or at 70, when benefits max out.

When you apply for benefits, Social Security uses your 35 highestearning years to calculate your check. Each year is "indexed" — adjusted to reflect wage and price inflation.

When estimating your future benefit, however, the agency assumes no future growth in wages or prices, said economist Laurence Kotlikoff, creator of the Maximize My Social Security claimingstrategies site. That often creates "lowball" estimates for younger workers, he said.

On the other hand, the agency could be overestimating your benefit if your income has peaked because it assumes you will continue earning roughly the same amount until you apply for benefits.

Your My Social Security account includes a link to a retirement calculator that allows you to adjust your average future earnings.

Other circumstances can upend the estimates. Some people will qualify for spousal or survivor benefits that are larger than what they earn on their own record. Retirees with minor children can get child benefits that boost their checks.

Tricky pension provisions can lead to nastier surprises for people who worked for certain government agencies or were employed abroad.