If you apply for Social Security benefits before your normal retirement age (66 for workers born in 1943 through 1954), you’ll be asked whether you plan to keep working — and, if so, how much you expect to make. How you answer will determine whether Uncle Sam reclaims some of your benefits.

For 2010, the so-called benefits test applies if you make more than $14,160; for every $2 you earn over that limit, you’ll lose $1. 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 $15,840 over the limit, you would lose half of the excess, or $7,920.