What is my 1040X Tax Due Amount?

[RSquirrel]

I e-filed MFS returns for my spouse and myself, including EFT payments due for both. Now, due to an error I discovered after e-filing, I will be re-filing (by mail) a MFJ 1040X, resulting in additional taxes due. I don't want to wait for the original (wrong) returns to be processed, as I might incur a late penalty.

For sake of this example, let’s say my spouse’s MFS tax bill was $1,000 and mine was $1,500. If my MFJ 1040X tax due is, say $3,000, do I submit a payment of the difference ($500), or do I pay the full $3,000, and expect the original $1,000 and $1,500 payments to be refunded?

[fanfare · Accepted solution]

form 1040X tells you - Line 20 - what additional tax you owe as a result of your amendment and that is the amount you should pay.

Write "for 2019 1040-X" on your check with your SSN and phone number.

[RSquirrel · Accepted solution]

Initially, your response didn't seem to answer my question. I say that because it wasn't apparent to me that the IRS would know that I had already submitted a (partial) payment, and so take that into account when computing the additional amount. But when I created an amended return (based, of course on the original return) somehow my initial payments had been accounted for. What I finally realized is that once the return is "accepted" by the IRS, even though the return has not yet been processed, the system is aware of the previous payment and reduces the new payment accordingly.