My friend is just now doing his 2013 taxes. For 2013 he did not pay estimated tax on his business but his wife's federal pension check had the W-2 withholding.
He is likely to have a tax bill of a several thousand plus the penalty.
He is also in arrears for prior year taxes and those arrears are being taken out of his wife's federal pension check.
If he manages to come up with the cash to pay the full amount due for 2013 will the IRS apply the payment to the 2013 taxes or apply it first to the balance due on prior years?