At this time, Iowa's only income tax reciprocal agreement is with Illinois.
IOWA AND ILLINOIS RECIPROCAL AGREEMENT
Iowa will tax any Iowa-source income received by an Illinois resident
that is not from wages or salaries. Illinois will tax any Illinois-source
income received by an Iowa resident that is not from wages or salaries.
Examples of income that are not wages and salaries and, therefore, not
covered under the Iowa-Illinois Reciprocal Agreement are Iowa gambling
winnings and unemployment compensation for employment in Iowa.
Iowa Resident Working for Wages or Salary in Illinois
An Iowa resident working for wages or salary in Illinois should complete and file Illinois form IL-W-5-NR Employee's Statement of Nonresidence in Illinois with
the employer so that the employer will withhold Iowa income tax.
Illinois Resident Working for Wages or Salary in Iowa
An Illinois resident working for wages or salary in Iowa should complete and file the IA 44-016 (pdf) Employee's Statement of Nonresidence in Iowa with the employer so that the employer will withhold Illinois income tax.
Tax Withheld in Error
If Illinois income tax has been mistakenly withheld from the wages or salary of an Iowa resident, the Iowa resident must file an Illinois income tax return to get a refund. Any questions on how to complete the Illinois return should be directed to the Illinois Department of Revenue at 1-800-732-8866.
Illinois residents who have had Iowa income tax withheld in error from
their wages and have no other Iowa-source income must file an Iowa income
tax return requesting a refund. They should complete Steps 1, 2, and
3 of the IA1040, show 0 on line 1 of Step 4, line 26 of
Step 5, and line 56 of Step 8, write Illinois resident tax withheld in error on
the face of the return. On the back of the IA 1040 on lines 60, 67, 68,
69, and 70, enter the Iowa tax withheld, sign the return and include copies
of W-2s with the return. Copies of federal and Illinois returns
must be enclosed.