Like the rest of the flat tax plans, the Forbes plan adds the payroll taxes right on top of the "flat" tax. Just take the tax rate he is pushing and add the 15.3% payroll tax rate to it.
"A family of four would pay no federal income tax on its first $46,165 of income. Exemptions for a family of six-mom, dad, four kids-would be $65,930." Well, why not? Do we want an even higher percentage of the population not paying income taxes? And what about the $5,043.65 FICA tax the family of six is paying? Why does he not take that into account? Are we just supposed to ignore that?
Under the Fair Tax, the family of six would pay $7762.50 Fair Tax after taking the rebate into consideration, or 11.77%. That's if they spend every cent on taxable goods and services. If they invested, gave to charity, or paid tuition just 10% they would pay $6246.11, just 9.47%. But it's really up to them, isn't it? Source: http://www.pafairtax.org/calc.php