I moved last year. Why did adding W-2s from my current state (Nevada) affect the state refund amount from my previous state (Nebraska), as in make it drop?

[Bombadillll]

I moved from Nebraska to Nevada in 2018. I had one W-2 from Nebraska and two W-2s from Nevada. I noticed my initial state refund for Nebraska dropped after the two Nevada W-2s were added. I understand why the amount of my federal tax return dropped, but why did adding W-2s from my current state (Nevada) affect the state refund amount from my previous state (Nebraska)?

[DanielV01 · Accepted solution]

It is the way Nebraska calculates part-year resident tax.  While Nebraska does not tax your Nevada income, it does factor in all of your income to determine Nebraska tax.  Nebraska pretends that all of your income is taxable in Nebraska, and then prorates the tax to the percentage of income taxable in Nebraska.

When this happens, it is possible that tax refund is reduced.  This can be because now any deductions and credits are also prorated on your tax amounts, and this would lower your refund.  Also, when factoring in all of your income, you could have some credits reduced or eliminated, and in some states higher tax brackets come into play.  

Any of those things can be affecting the Nebraska refund.  Again, Nebraska still is not taxing the Nevada income, but they do use it to determine how much tax you pay on the Nebraska income.