Social Security benefits may be tax free or includible in gross income at 50% or 85%. This depends on a couple’s income, Social Security benefits, and tax-exempt interest. The fact that the benefits are payable to a third party does not change the tax result; the Social Security checks are being used for the taxpayer’s benefit.
The legal transfer of property, rights, or interest to another person called an assignee. You cannot avoid tax on income by assigning the income to another person.