Ending TLS Client Authentication Certificate Support in 2026

API Announcements
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Let’s Encrypt will no longer include the “TLS Client Authentication” Extended Key Usage (EKU) in our certificates beginning in 2026. Most users who use Let’s Encrypt to secure websites won’t be affected and won’t need to take any action. However, if you use Let’s Encrypt certificates as client certificates to authenticate to a server, this change may impact you.

To minimize disruption, Let’s Encrypt will roll this change out in multiple stages, using ACME Profiles.

For the full details and schedule, please see our blog post.

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Do *NOT* remove TLS Client Auth EKU!
Staging API timeline for default issuance profile changes
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As described in the blog post, the tlsclient profile is now available in staging and will be made available in production on October 1st.

It is currently the same as the classic profile. Anyone who will need more time to migrate can use that profile until May 13, 2026.

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The tlsclient profile is now available in production.

It is currently the same as the classic profile. Anyone who will need more time to migrate can use that profile until May 13, 2026.

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