Hello again tbrn,
If your husband physically works in the state of Kansas, which it sounds like he does, then he will be liable for state tax in Kansas, and he will also be liable for filing a state tax return in Missouri since he is a resident in that state.
However, since the nature of your husband's job is that he is a delivery driver, his income will all be considered as derived from the state of Kansas. This is because his company is based in Kansas and this is apparently where he starts and ends his work day. The fact that he may cross the state line during the day to make deliveries will still not attribute any of his income as being from a Missouri source. He is merely making deliveries in that state. That being the case, here is what will happen.
Your husband will file a state tax return with the state of Kansas as a non-resident, and he will pay Kansas state tax on his income from that company. At the same time he will file a tax return (or a joint return with you) in the state of Missouri since he is a resident here. However, on your Missouri return you will then claim a credit for the state taxes paid to Kansas. If the Kansas state taxes are higher than what the Missouri taxes are on that same income, then he will owe no Missouri state tax on the income from that job.
The Kansas state income tax rate for individuals is 6.45% on any income of $30,001 or higher per year. This is higher than Missouri's 6.0% rate on that same income, so the net effect is that once your husband claims credit for the taxes paid to Kansas, he should not owe any additional tax to Missouri on the income from that job.
In general, states allow you to claim credit for taxes already paid to another state in order to prevent double taxation
on the same income. This will apply in your husband's situation.
When you worked for the health care company some years ago, if you physically worked from an office in Missouri and all of your health visits were in Missouri, then you should not have had to pay any Kansas state taxes. Your state taxes are not based on where the company is located. They are based on where you physically work and where you reside. Those are the two states where you have to report. But again, even though you may have to file in two states, your resident state will allow you credit for any tax paid to the state where you are physically employed to prevent the double taxation issue.
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