If you hold more than one job during the year—either at the same time or successively—too much Social Security could be withheld from your pay. This is because each employer is required to withhold the tax, but no taxpayer has to pay the full tax on more than the annual limits. If wages from two jobs pushes you over the limit, too much tax will be withheld. You get a credit for the excess when you file your tax return for the year.