Originally Posted by
richarddd
The usual problem is if it seems you are trying to evade taxes by shifting taxable income from one year to another. If the overpayment would not meaningfully lower the total amount of taxes you would pay, there should not be a problem. The relevant regs talk about the reasonableness of the overpayment, reasonable not being a very precise standard.
I think you're thinking of the federal deductibility of state income tax overpayments, which some IRS rulings (
not regulations), starting with 71-190, limit to a reasonable amount. There is no corresponding concept for the creditability of an overpayment against the tax you're overpaying. If you overpay your federal income tax by a billion dollars, you get a refund of a billion dollars.