Your selection should not duplicate your resident state of California

[LenaH · Accepted solution]

For that screen, your answer would be no because it will create a part-year resident return for California. Your state residence for 2020 is California. Usually your state of residency is the place you intend to be your permanent home. You aren't living in the state for a temporary purpose. It's the place you return to after a vacation, business assignment, or away at school. You can only have one permanent home. States often refer to this as your domicile.

Therefore, you would need a full-year resident return for the State of California. Washington state does not have an income tax return. As a resident, you are liable to pay California state income tax and you will not get a credit on your California return because you did not pay tax to another state. 

Please make sure you've filled out the Personal Info section correctly:

1. With your return open, select My Info in the left-hand menu.
2. Confirm you have California as your resident state. 
3. Scroll down on the Personal info summary screen to Other State Income, and
4. Then, on the Personal info summary screen, scroll down to Other State Income, and select Edit.
5. At the Did you make money in any other states? question, answer Yes and make sure your nonresident state is selected from the drop-down.
6. Select Continue to return to your Personal info summary.

[LenaH]

Yes, as a California resident, you are taxed on all income regardless of source.

@goblueping