Multiple jobs, multiple states, & W4s

I believe you are asking about 2026 taxes and moving forward. You did just learn, we are here year round and you can always come ask questions.

For 2026:

• MFJ, both KS residents, one job in MO.
• MO taxes based on total income times MO percentage of income earned. There is nothing you can do about how the tax is calculated but understand it.
• Next, KS taxes your entire income and gives you a credit for the income being taxed in both KS and MO. This is your problem.
• MO tax rate is much lower than KS. This means you owe KS each year on the difference between the credit and KS tax.
  • To fix this situation pay an extra 1 - 1.3%:
    • Submit a Kansas Form K-4 to your HR department and ask them to withhold an Additional Amount for KS
    • If HR won't do that, make estimated payments to KS throughout the year. You can make an estimated payment with each paycheck or whenever you want. Pay here
    • Another option, is to have the KS spouse withhold more taxes at their job. The w4 can be filed with the box to withhold an additional state amount filled in

For example: Your paycheck shows you earned $1200 gross, not take home, then  $1200 x 1% = $12 to pay KS.

I recommend that each quarter, you take a look at your total family income, interest, capital gains, all of it and see if you have enough withholding to avoid additional tax and possibly penalties. The KS tax rate varies from 5.2% - 5.58%. The higher limit is for MFJ above $46,000, which I am guessing would be your tax rate.

You want to avoid Penalty and Interest