Knowledge Base

Knowledge BaseEmail (S/MIME)

How to Set Up S/MIME for Gmail in Google Workspace?

Updated on December 10, 2025

How to Set Up S/MIME for Gmail in Google workspace?

Similar Questions: How do I install an S/MIME certificate in Gmail?

What are the steps to enable S/MIME encryption in Google Workspace?

How can I configure Gmail to use S/MIME for secure email?

How does Gmail handle digitally signed messages with S/MIME?

Overview

S/MIME (Secure/Multipurpose Internet Mail Extensions) is a widely adopted protocol for securing email communication through encryption and digital signatures. Gmail supports S/MIME for Google Workspace accounts, allowing users to send encrypted emails that ensure confidentiality, integrity, and authenticity.

A step-by-step guide to installing S/MIME certificate and setting up hosted S/MIME in Gmail:

S/MIME encrypted email message

Requirements:

To use S/MIME in Gmail, you must:

Have a Google Workspace account (not a free Gmail account).

Be on a supported edition like Enterprise Plus, Education Plus, or Frontline Plus.

Have S/MIME been enabled by your administrator in Google Admin Console.

Possess a valid S/MIME certificate issued by a trusted Certificate Authority (CA).

Enable S/MIME Encryption in the Admin Dashboard

Select User Settings. Change the Enable S/MIME encryption for sending and receiving emails option.

Enable S/MIME encryption in Google Admin dashboard

Check Enable S/MIME encryption for sending and receiving emails and Allow users to upload their own certificates.

Click Save button.

Enable S/MIME encryption and allow users to upload certificates

Install the S/MIME Certificate in Gmail

In the Accounts tab, click the edit info link outlined in red below.

Accounts tab in Gmail Settings

Click Upload a personal certificate and upload your S/MIME certificate bundle.

Upload a S/MIME certificate to Gmail

Enter the password associated with the S/MIME certificate bundle. If you obtained the certificate as a p12 or .pfx file from a certificate authority, they must have also given you the password.

The certificate's private key is encrypted with the password, so if you lose it, you won't be able to import the certificate.

Enter the certificate bundle password

Select Use this certificate and click Save Changes.

Gmail encryption settings

You should now be able to send and receive encrypted messages on gmail.com and with the Gmail mobile app. Gmail should also automatically digitally sign outgoing mail.

The screenshot below shows the details of an encrypted message on the Gmail iOS app. The sender is marked as Verified because the message is digitally signed. A green padlock-and-plus-sign icon is displayed with the mention Enhanced encryption (S/MIME).

S/MIME Sign and Encrypt by Default