Aug 10, 2021 · Register to use milConnect. Last Updated 8/10/2021 Find a TRICARE Plan Find a Doctor Find a Phone Number Your Contacts DMDC/DEERS Support Office (DSO) Toll-free: 1-800-538-9552 TTY/TTD: 1-866-363-2883 Fax: 1-800-336-4416 (Primary) or 1-502-335-9980 (Alternate) Update DEERS Online ....