State tax filing

Dear @CatinaT1,

 

Thanks a lot for your prompt response and very useful information. So, for me to better understand your comment, here are two small follow-ups. Can you please confirm?

 

  • You suggested that I should file these incomes/payments as both CA income on my CA tax return and also IL income on my IL tax return, right? If so, isn't there a problem with double counting, that is, counting the same income twice?
  • Does it matter how my former IL company processed those pay-stub (and W2) for state tax purposes, for example, taking out IL taxes from the paychecks based on IL company address, or taking CA taxes based on my home address in CA? Actually, I'm not yet sure how they did it (waiting for their response), but just wondering if that aspect impacts on how I should file my IL return and CA return. 

Greatly appreciate your help.