Please ensure you use the same browser to login to CORE as you do to Revenue/ROS.

Click on the link below and follow instructions to register with ROS

Useful Tips for Signing Electronically with ROS

  • ● Has your firm registered with ROS and have you a sub-cert in your own name?
  • ● Ensure you are not using the Firm’s cert, it must be a sub-cert in the name of the individual signing.
  • ● Is your name spelled correctly and corresponds with your ROS sub-cert?
  • ● Have you used the correct email address associated with your ROS sub-cert?
  • ● Is the ROS sub-cert saved on the browser on the PC/laptop you are using?
  • ● Are you using the correct ROS Registration Number?
  • ● Does your browser setting Allow All Cookies?


If you are still having difficulties with ROS, please contact their Technical Helpdesk on ROS Technical Helpdesk at