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It sounds like a cruel joke.

After a lifetime in the work force, you call it quits at 62 to claim Social Security benefits and begin a long and satisfying retirement.

Then, the worst economic calamity since the Great Depression hits with the vengeance of Hurricane Katrina, decimating your nest egg and depleting the value of your home. Faced with the painful reality that you must go back to work, you count yourself lucky to find a job at a time of high unemployment.

And your reward? The federal government suspends your Social Security benefits.

Say hello to the confusing and controversial Social Security earnings test. This provision of the law says sure, you can claim your benefits as early as age 62, but you can't necessarily keep the cash if you work before reaching your normal retirement age (66 for workers born in 1943 through 1954).

The earnings test cost a quarter of a million working Social Security beneficiaries about $100 million each month in 2009, according to a ballpark estimate Social Security officials made for Kiplinger.

No one knows how much of that figure is a result of retirees being forced by deteriorating finances to go back to work. But it's clear that anyone who claims Social Security benefits early -- or who's thinking about it -- needs to understand what's going on here.

And that includes the increasing number of 62-plus men and women who have lost their jobs and, as they've struggled to find new ones, have filed for Social Security early to pay the bills until they can restart their paychecks. There's been a big jump in the number of Americans claiming benefits early since the recession began driving unemployment higher.

How the earnings test works

If you apply for Social Security benefits early, you'll be asked whether you plan to keep working and, if so, how much you expect to earn -- to determine whether you'll be stung by the earnings test.

For 2012, the test applies if you make more than $14,640. And for every $2 you earn over that limit, you'll lose $1 of benefits. Suppose you claim benefits at age 62 and your monthly benefit is $1,500 (and you estimate that you'll earn $30,000 during the year). Because $30,000 is $15,360 over the limit, you would lose half of the excess, or $7,680, in benefits.

The Social Security Administration doesn't trim each check by a proportional amount. Your benefits are withheld completely until the squeeze is satisfied. In this example, you'd get no benefits for five months (covering $7,500 of the lost benefits), and your benefit in the sixth month would be $1,500 minus the final $180 claimed by the earnings test, or $1,320.

In the year you first claim benefits, the test basically lets you ignore money you made before you applied and squeezes benefits based on monthly earnings for the rest of the year. In the calendar year you reach normal retirement age, a more lenient earnings test applies: You lose $1 for every $3 in earnings over $38,880 before your birthday. Starting in the month you reach normal retirement age, there's no earnings test. You can earn as much as you want without losing a dime in benefits.

Note: For purposes of the earnings test, only wages from a job or self-employment income count. Investment earnings, pension benefits, money drawn from an individual retirement account or 401k, or even lottery winnings do not.

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Not the honor system

Although you will be asked to estimate your earnings, your projection isn't the final word. When you file your tax return, the Internal Revenue System lets the Social Security Administration know exactly how much wage and self-employment earnings you report.

That figure is compared with your estimate, and the government reconciles the books by either sending you a check -- if your estimate of earnings was too high and the earnings test clawed back too much of your benefits -- or dunning you for a balance due.

This final point is particularly important if you unexpectedly return to work while you're subject to the earnings test. You should let the Social Security agency know of the change in circumstances as soon as possible so that your benefits can be trimmed if you run afoul of the earnings test. Failing to do so could come back to haunt you later. If the tax return you file shows earnings that should have triggered reduced benefits, you'll be asked to pay back the excess in a lump sum or see future benefits reduced.

A silver lining in the earnings test

Although the earnings test is often derided as an unconscionable 50% surtax -- because $2 in earnings can cost you $1 in benefits -- it's not as evil as critics complain. Benefits lost to the test are not gone forever. Instead, the law is designed to ensure that you recover any forfeited amount via higher monthly benefits later.

Remember, if you claim benefits before your full retirement age, your benefits will be permanently reduced (see the table below). But for any month you lose benefits to the earnings test, the Social Security agency will ratchet up future benefits.

Say you retire at 62, happy to accept the 25% haircut in benefits in exchange for collecting four years early. Then you have to go back to work and wind up forfeiting 12 months' worth of benefits. Basically, when recalculating your benefits at your full retirement age, you'll be treated as though you claimed benefits three years early, not four. Instead of having your lifetime benefits reduced by 25%, in this example you'd suffer about a 20% reduction going forward.

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And if your earnings during your period of forced re-employment are higher than one of the 35 years of earnings originally used by Social Security to compute your benefit, your monthly payments could rise even more.

The earliest age for full benefits

Through most of Social Security's history, 65 was the magic age. Claiming retirement benefits before then -- and you can start as early as age 62 -- meant accepting a lifetime reduction in benefits.

For folks retiring this year, though, the magic age is 66. And the age at which you can start collecting benefits without being docked for starting early -- or being threatened by the earnings test -- is increasing.

 
Birth yearFull retirement ageCut in monthly benefits if claimed at 62
1943-19546625%
195566 and 2 months25.83%
195666 and 4 months26.67%
195766 and 6 months27.5%
195866 and 8 months28.33%
195966 and 10 months29.17%
19606730%

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