Last Modified: 7/19/2018 Location: FL, PR, USVI Business: Part A
Home office registration FAQ
Q: What is EUS?
A: External user services (EUS) is a help desk offered by Centers for Medicare & Medicaid Services (CMS) for assisting with the registration and use of the EIDM (enterprise identity management system) system for provider and Medicare administrative contractor (MAC) users. The EUS help desk can be reached:
Toll-Free Telephone: 1-866-484-8049 (Monday-Friday, 7:00 a.m.-7:00 p.m. eastern time [ET])
TTY/TDD: 1-866-523-4759 (Monday-Friday, 7:00 a.m.-7:00 p.m. ET)
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First Coast Service Options (First Coast) strives to ensure that the information available on our provider website is accurate, detailed, and current. Therefore, this is a dynamic site and its content changes daily. It is best to access the site to ensure you have the most current information rather than printing articles or forms that may become obsolete without notice.