Twisp Medical Clinic. 541 W. 2nd Ave, Twisp Washington 98856. P.O. Box 1340, Okanogan, WA 98840. Phone: (800) 660-2129. Fax: (855) 206-6183. Hours: 8am-5pm Mon – Fri. WITH COVID CASES RISING, WE ARE NOT ALLOWING VISITORS/VENDORS IN OUR CLINICS AT THIS TIME. PATIENTS MAY HAVE ONE FAMILY MEMBER WITH THEM. Thank you for understanding..