W-2 two states reported

[J-Cubed]

My son lived and worked in KS from January to July. During that time, he made $22,180.85. He moved to MO in July and lived and worked in MO from July to December. During that time, he made $29,508.38.

Box 1 of his W-2 is $51,689.23.

Box 16 of his W-2 reflects $51,689.23 for MO and $22,180.85 for KS.

His tax preparer has advised him that the Box 16 KS figure of $22,180.85 is correct but that the Box 16 MO amount should only be the $29,508.38 he was paid after moving to MO, not the entire $51,689.23 amount for all of 2024. Is the preparer correct and should my son request a corrected W-2? 

[Vanessa A]

Yes, the preparer is correct and he should request a corrected W-2.  Only the income that is earned while a resident of that state or in that state would be taxable to that state.