> ## Knowledge Base Index
> Fetch the complete knowledge base index at: https://help.flexbox.cloud/sitemap.xml
> Use this file to discover available pages before exploring further.
> Pure-Markdown content can be obtained by appending a '.md' suffix to the content URLs listed in the sitemap (without the trailing slash).

# Which mail systems / clients support S/MIME Certificates?

S/MIME Certificates are natively compatible with all major email clients, internet browsers and mobile devices.

**Email clients:**

* Microsoft Outlook
* Apple Mail and MailMate
* Samsung Mail
* CipherMail para Android
* eM Client
* Mozilla Thunderbird
* Gnome Evolution
* SeaMonkey


**Web clients:**

* Outlook Web App (Exchange Server 2013 or 2010)
* Outlook on the Web or Exchange Online (Microsoft 365 or Exchange Server 2016)
* Gmail (G Suite Enterprise or Education)
* Zimbra Web Client
* Zoho Mail (Mail Premium or Workplace Professional)


**Operating system (OS):**

* Windows
* Linux
* MacOS
* iOS
* Android


**And any other email client or system that supports S/MIME certificates.**


If you don't have an S/MIME Certificate or need to renew your existing one, check out our offerings: [https://flexbox.cloud/en/secure-email-smime-certificate/](https://flexbox.cloud/en/secure-email-smime-certificate/)