What exactly does "being taxed for California" mean? Do you mean that California tax is being withheld from your pay?
And what do you mean by "taxed for California and Washington"? Washington does not have any personal income tax. You could not have Washington income tax being withheld from your pay, because there is no Washington income tax. Are you talking about the deduction for the Washington Workmen's Compensation Fund?
Do you sometimes travel to California for work?
