Apartment in California. We will both be flying back and forth and spending about half the year in each apartment. What is our state tax responsibility.

It appears his State residency is in Calfornia and yours is in NY.

(For future posts, please put a title in the title portion and the message in the other section or else it's very hard to follow.)

I agree with JudyKayTree. Both California and NY will claim the person who is maintaining the apartment is, in fact, a state resident and subject the salary of that person to their state income tax.

But they will use the income from the OTHER state to push the salary to a higher tax bracket.