To qualify for this credit, you must be a resident of Washington, which means that you must be physically present and reside in Washington for at least 183 days during the tax year. Applicants not physically present in Washington state for at least 183 days are not eligible for the credit.
If you are in the military, and live outside of Washington state, but are married filing jointly, and have a spouse that resides in Washington, you’re still eligible and should apply.