I received a letter from the IRS that I owe 1,544 from 2015. I took a 45 day medical leave, paid for by a third party. What do I do if this was filed incorrectly?

[Critter]

Did you forget to enter some income ?  Is the IRS correct ?  If so agree to the changes & pay the bill.

If not then the notice has directions on how to dispute the change.

[Hal_Al · Accepted solution]

Third party sick pay may or may not be taxable. If you got a W-2, with an amount in box 1, or a 1099-R, it is taxable. The rule is if you paid the premium, with after tax money, the sick pay benefit is tax free. If your employer paid the premium (as in most cases) or you paid the premium with pre-tax money, the benefit is taxable.

I would appear the IRS got a copy of a W-2 or 1099-R and have added the taxable income. If you agree with them, just pay them. If you disagree, write to them and explain why.

If you want to verify the IRS numbers, enter your return and add the income. Do not save your changes, unless you made a copy or saved a pdf of the original return. If you decide to submit an amended return, see https://ttlc.intuit.com/questions/1894381-how-to-amend-change-or-correct-a-return-you-already-filed