I completed work in Illinois for a corporation that is in Missouri. My 1099 says Missouri. Do I need to pay IL taxes?

You received an IRS form 1099-NEC for self-employment income that was performed in Illinois.

If you are an Missouri resident and you performed work in Illinois, the state of Missouri has a claim on your income.

The state of Illinois may have a claim on the income because the income is Illinois sourced.

You would file as a nonresident.  Illinois filing requirements may be found here.

• a nonresident, you must file Form IL-1040 and Schedule NR if
  • you earned enough taxable income from Illinois sources to have a tax liability ( i.e., your Illinois base income from Schedule NR, Step 5, Line 46, is greater than your Illinois exemption allowance on Schedule NR, Step 5, Line 50), or
  • you want a refund of any Illinois Income Tax withheld in error. You must attach a letter of explanation from your employer.

If you pay income tax to Illinois, you may be eligible for a tax credit on your Missouri income tax return for taxes paid to another state.

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