What happens if the issuer won’t cooperate? They can be subject to fines at the IRS. The money was not made available to you till 2018 and the check was dated 2018. This is an error that they need to fix. If not they are potentially subject to fines and even lawsuits.
https://www.irs.gov/government-entities/federal-state-local-governments/increase-in-information-retu... Do note that you should save all documentation related to your conversations of their refusal and whom you spoke with.
You can call the IRS at 800-829-1040 and explain your situation. The IRS will contact the company that issued the 1099 and request a corrected form. Do note this will take time and you still need to get your return done.
If they refuse to fix it you still can address it by filing an information statement. You will add the 1099 in as reported and then you will be able to adjust the amount and have to provide an information statement to the IRS with your return.
For example, you could show the $x payment on your return (on line 21, or on a Schedule C), and then explain the $x overstatement. Report the Income on schedule C and take a deduction under other expenses, for the incorrect amount, call it something like "1099 issued in wrong year".
You could do so in a statement or footnote by showing $x on line 21, but adding “see statement.” The statement might say:
Erroneous Form 1099-MISC $x
Less error amount $x *Amount was not paid nor issued till 2018 and will be properly reflected on my 2018 return. Issuer refuses to correct.
Net to line 21 $
Sadly this will also cause you to have to file by mail. If you file schedule C, you could put under other expense.
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