My husband will live/work in CA during the week (all year) while I reside in AZ in the house we own. We have one income. How should we plan to file our taxes for 2020?

[Critter]

You will file one  federal return  and then a non resident CA return and a resident AZ return  and you MUST complete them in that order in the Turbotax program to get the correct credit on the AZ return for the taxes paid to CA. 

[SteamTrain]

@Critter   @jtorres614 

I think it's reversed for an AZ Resident/CA non-resident situation.  CA/AZ cross border workers prep taxes in a different order from most of the rest of the country. The AZ Resident is done first, then the credit is on the CA non-resident tax return.

"Important: As an Arizona resident, nonresident returns filed with the following states DO NOT QUALIFY for the credit on the Arizona return:  Alaska, California, District of Columbia, Florida, Indiana, Nevada, New Hampshire, Oregon, South Dakota, Tennessee, Texas, Virginia, Washington and Wyoming.
You may be able to claim a credit for taxes paid to Arizona on the nonresident return filed with any of those states listed above."

top of page 2  of the 2019 AZ form 309 instructions: 

 https://azdor.gov/forms/tax-credits-forms/credit-taxes-paid-another-state-or-country

___________________

A bigger issue I see is whether the husband might really be considered a CA resident by CA, with 4-5 nights a week in CA all year....and only one year? or continuing to be the case for for several years??  Those who push the 6 month limit (183+ days) living in CA are getting themselves into a hazy area.  (but that's just a personal opinion)

[Critter]

Yes ... I forgot those 2 states do things backwards.  I highly recommend you seek local professional help this year for the state returns so you are educated on the proper way to file them.