Notification of Discontinuation of Old Format Keio IDs and Mailing Lists (March 2025)

Keio Single Sign-On System (keio.jp) underwent a system change in November 2014.
While it had been possible to continue using "Old Format Keio IDs" and "Old Format Mailing Lists" acquired before November 2014, as ten years have passed since the change and the majority of users, including students, have transitioned to the new system, we will discontinue them as of March 31, 2025.

（Updated:　June 21, 2024）

Due to keio.jp authentication system update, Old Format Keio ID will be not use as authentication IDs from September 15, 2024(planned)(Usable as email addresses until March 31, 2025.).
For details, please see Updating the keio.jp authentication system (1st report).

[Discontinued Items]

Old Format Keio IDs (e.g.):

keiotaro@**.keio.jp (** represents a2, z7, etc.)

Old Format Mailing Lists (e.g.):

keiotaro@ ml.keio.jp

You do not need to migrate the sent and received data in your mailbox (since the mailbox is shared between the new and old formats).

For those using Old Format Keio IDs and Mailing Lists, we kindly ask you to switch to the new format as soon as possible.

New Format Keio ID (Keio Apps ID) (e.g.):

keiotaro@keio.jp,　keiojiro.**@keio.jp (The subdomain such as a2, z7, etc., is not added between "@" and "keio.jp.")

New Format Group (e.g.):

keiotaro-group@keio.jp ("-group" is added immediately before "@")

For information on how to confirm your New Format Keio ID (Keio Apps ID), please refer to the following reference information.

Some actions that users need to take when switching (examples)

If you are already using the New Format Keio ID (Keio Apps ID) and New Format Mailing Lists, the following tasks are unnecessary.

• Inform people who contact you with Old Format Keio IDs and Old Format Mailing Lists that their contact information has been changed.
• For external mailing lists with Old Format Keio IDs e-mail addresses, change the registered contents (or ask the mailing list administrator to change them).
• If the address of the Old Format Keio ID is registered as the ID for an external service or the contact e-mail address for the service, change it.

Please refer to "Checklist for handling the discontinuation of the old format Keio ID".

See Also

• keio.jp User's Manual "About Keio ID"
• The new Keio Mail(Internal network or keio.jp authentication required)
• About migration of the mailing list (Internal network or keio.jp authentication required)
• Keio Apps ID: ID confirmation method (Internal network or keio.jp authentication required)