Electronic instructions for use (eIFU) are legal today for the large majority of professional-use medical devices in the European Union, the United Kingdom, Switzerland, the United States, Canada, Australia, Brazil, Saudi Arabia and Japan. The rules differ in the details, but they share one shape: eIFU is permitted for devices used by healthcare professionals, paper remains mandatory for devices used by lay persons, and every manufacturer must be able to send a printed copy on request. This article reviews the legal status of an eIFU implementation market by market, with the primary references at the end, as of November 2026.