Turbotax is saying I've made double the income for state-returns (Part Time Residencies in NY, NJ)

[ms_questions]

In line 16 of State Wages/State Tips it reads this I made. (numbers altered for privacy)

NJ - $53000

NY - $50000

~02/01/2019 - NYC Job Starts, Live in NJ

~04/01/2019 - Moved to NYC

When I attempt to file NJ state returns, it's reporting that my total income is 103000, so the sum of those two lines. Rather than just one of those numbers. And it's asking me how much of that income I made while living or working in Jersey. 

Is my W2 wrong? Or is Turbo Tax not calculating this correctly?

[taxes_are_confusing]

A few things to note.

NY has a weird rule that requires your company puts your full federal amount in the W2 box for NY state income. As far as I know NJ does not have this same rule, so your NJ state income should be roughly equivalent to the income received by your employer when you were a NJ resident, assuming you changed your address with your employer when you moved.

It is now up to you to allocate what percentage of your wages actually belong to NY when filing your NY state return. Assuming you worked every day of the year in the NYC office then your NY wages should be 100% of what is on your W2 for NY state income. If you have a more complicated residency situation read through NY IT-203-I to figure out what to do.

Your NJ wages should be income that you earned during your period of residency in NJ for those 2 months.

Note that during those 2 months of NJ residency you were double taxed by both NY and NJ, so you can claim a credit with NJ for taxes paid to NY.

I know you randomized your numbers, but it sounds like your NY and NJ amounts are about the same so are you sure your employer has your new NYC address as your place of residence?

[ms_questions]

Thank you for this response! This is so helpful. I never knew the importance of a W4 form until now. It's my first situation where I moved while maintaining the same job. So no, I never informed my employer, so perhaps that's why the state amounts are referencing about the same number.

I imagine the steps here are to:

1. Inform the employer and get a corrected W2? 

2. In the case that the W2 is not sent back in time. It looks like this error will not affect my federal tax returns, but just my state returns. Turbotax is reporting I do not owe any tax to NJ after I filled out the forms correctly, and it looks like I do owe money to NYC. Is there any harm for me filing my return by Apr 15 when I know my W2 form is wrong in line 16?