In 2012, the IRS began verifying the validity of voluntary tax withholding (VTW) amounts
on tax returns pre-refund due to an increase in identity theft with non-compliant
VTW claimed on Social Security benefits. Therefore, if the taxpayer elects voluntary
federal income tax withholding on their Social Security benefits, a copy of Form SSA-1099
must accompany his or her federal tax return to verify the claimed VTW. The Social Security Benefit Statement Instruction Sheet, Form SSA-1099-F2-INST now instructs beneficiaries to attach a copy of their Form
SSA-1099 to their federal tax return if an entry appears in the VTW box on the form.