Regardless of age, as long as individuals are employed at work covered by Social Security, they must pay standard Social Security taxes, reports AARP. The standard Social Security tax rate on wages earned is 12.4 percent as of 2015, states About.com.
Half of the 12.4 percent Social Security tax is paid by the employee and half is paid by the employer, according to About.com. Although self-employed people must pay the entire 12.4 percent, they can deduct half the total when they file their income tax return, states AARP. Income is subject to Social Security tax until it reaches the maximum wage base, which as of 2015 is $118,500, reports About.com. Any earnings over the wage base are Social Security tax-free.
Working while receiving Social Security benefits can also push employees into a higher income bracket, causing a portion of Social Security benefits to be taxed, according to Market Watch. Combined income is a combination of employment wages, interest from municipal bonds, IRA distributions and half of Social Security payments. If the total is below a maximum level, Social Security benefits are not taxed, but if the income exceeds that level, a portion of Social Security payments becomes taxable to a maximum of 85 percent.