Hospitals: Washington requires hospitals keep their adult patient records for ten (10) years, and minor patient records for ten (10) years or until the patient reaches the age of 21, whichever is longer.
Physicians: Washington offers limited medical records retention guidance for private practices. Consult LINK for more on what to do when your state offers limited legal guidelines for records retention policy.
WASH. REV. CODE § 70.41.190
https://bit.ly/3PGu7dA