Well, it sounds like you consider your "tax home" to be in Washington state. So, the bottom is if you can convince your Company to agree, there shouldn't be a problem with not reporting you as an Oregon based employee.
I've encountered this issue in the past and the one stickler that has come up is that particularly in Sales, there are often multiple employees in various states (some states either do not have an income tax like Washington, Texas, Florida, etc.) or the applicable states' income tax rates are lower than where the Company's headquarters are located & if the Company takes the approach you suggest than they should take the same approach for everyone in similar circumstances whether than results in a lower state tax for the individual or not.
That's why I'm saying from a practical standpoint it really depends upon what you can convince the company to do. Often time they still consider someone in your situation to be "based" in Oregon & consider that to be your "tax home". Of course if you live in Washington, and are filing a Non-Resident return in Oregon, you are only talking about the state income tax withholding and should be getting most of it back when you file your return anyway. However, some of these border states where one state has a state income tax and a bordering state doesn't the state with the income tax may or may not have a "tax treaty" with the bordering state that determines the tax treatment. I haven't attempted to research the current situation with Oregon/Washington but I know of no such treaty in that particular situation.
Just checking in to see if you've had a chance to discuss your circumstances with your Company.
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