Lived/Worked in California all year, docile is in Missouri. My residency is...?

[tokani]

I moved to CA from Missouri for a 1-year temporary work/internship in March 2023, with employer-provided housing. For 2023 taxes, I paid both CA and MO taxes as I worked in both states during the year. I renewed my internship position in March 2024 and continued to live/work in CA the entire year. I have no income from MO in 2024, but my permanent address/docile is still my parent's home in MO. My DL, car, insurance, voter registration, and mail are all based in MO for the entirety of 2024. From my understanding, I need to file taxes for both CA and MO.

According to the facts and circumstances test, I would be considered a resident of MO. But as for CA, since I worked and lived entirely here, am I considered a full-year resident or part-year resident? Do I still need to complete the California Nonresident or Part-Year Resident Income Tax Return (Form 540NR)?

[KeshaH]

You're generally considered a resident for California if you live in California for at least nine months of the year. However, if you're present for temporary work with plans to leave after the job assignment is over, you can be considered a nonresident. You'd file a nonresident return in California and a resident return in Missouri. 

See: Guidelines for Determining Resident Status

[tokani]

I read through Section H. My work in CA is definite under a 51-week contract. I was on the back end of my first contract in February 2024, then I got my contract renewed for another 51 weeks in March 2024. I did renew my contract a third time this year 2025, but it is still temporary work. I don't think it applies to my 2024 taxes.

In total until Dec 31st 2024, I've lived in CA for 646 days (~1 year, 9 months) (March 26 2023 - December 31st 2024), apart from a few 3-10 day visits back home to MO a few times a year.

Another issue is that I'm not allowed to set my government-provided housing as my permanent address. Can a PO box work instead of an address?

[KeshaH]

If you're referring to the address to use on your tax return, you can use any address at which you receive mail. That can be your PO Box or your permanent address back in MO.