Yes, Social Security benefits are subject to a 15-percent levy via the Federal Payment Levy Program (FPLP).
Before the IRS levies 15 percent of your Social Security benefits, the IRS will issue a Final Notice of Intent to Levy, with appeal rights, if one has not already been issued. In addition, the IRS will issue a Final Notice Before Levy on Social Security Benefits, explaining that your Social Security benefits may be levied. Although the notice states that you have 30 days from the date of this notice to make arrangements to pay your tax debt. It may not stop the process that has been initiated by the IRS to the Social Security Administration to seize 15 percent from your monthly benefit.