Yes. Gambling income in the state where it was received, and the fact that Missouri withheld tax in and of itself means that you will file a Missouri nonresident return to determine how much of those withholdings will stay with Missouri or if you will receive a refund of some of them. When you prepare your state returns, you will want to prepare the Missouri nonresident return first.
That is because your resident state also taxes your income. In order to reduce the effect of double-taxation, your resident state will give you a credit for the taxes you will pay to Missouri on the gambling income. However, you will still have to file tax returns for both states (unless you live in a state without income tax, in which case you only file for Missouri).
I received several W2G's in 2024 for casino winnings in Missouri. On each W2G they didn't deducte federal taxes, but always deducted state taxes. However, my Win/Loss Statements total way more losses then my wins.
My question is.. Can I get a refund for all the state taxes deducted since my losses were greater then my winnings?
It depends. If your overall tax liability with your gambling income and itemized gambling losses result in lower tax liability, then yes, you would get a refund. If not, then no, you would not get a refund. The taxes withheld on the W2-g are treated like any other taxes withheld. They are added in with all your other taxes withheld and applied to your overall total tax liability.
In MO to claim your gambling losses you will need to itemize your return. MO only allows you to itemize your state return if you also itemized your federal return. If you do not itemize, you cannot take any sort of deduction for the gambling losses.