@import
CSS at-rule · 6 supported, 0 partial, 15 unsupported across 21 clients
Client Support
| Client | Category | Engine | Support |
|---|---|---|---|
| Gmail | webmail | Gmail Web | Unsupported |
| Gmail Android | mobile | Gmail Mobile | Unsupported |
| Gmail iOS | mobile | Gmail Mobile | Unsupported |
| Outlook 365 | webmail | Outlook Web | Unsupported |
| Outlook (New) | desktop | Outlook Web | Supported |
| Outlook Classic | desktop | Microsoft Word | Supported |
| Outlook iOS | mobile | Outlook Mobile | Unsupported |
| Outlook Android | mobile | Outlook Mobile | Unsupported |
| Outlook for Mac | desktop | WebKit | Supported |
| Apple Mail | desktop | WebKit | Supported |
| Apple Mail iOS | mobile | WebKit | Supported |
| Yahoo Mail | webmail | Yahoo | Unsupported |
| Yahoo Mail Android | mobile | Yahoo | Unsupported |
| Yahoo Mail iOS | mobile | Yahoo | Unsupported |
| Samsung Mail | mobile | Samsung | Unsupported |
| Thunderbird | desktop | Gecko | Unsupported |
| HEY Mail | webmail | WebKit | Supported |
| Proton Mail | webmail | Proton | Unsupported |
| AOL Mail | webmail | AOL | Unsupported |
| Fastmail | webmail | Fastmail | Unsupported |
| Superhuman | desktop | Blink | Unsupported |
Client-by-client behaviour for @import
Fully supports @import (6): Outlook (New), Outlook Classic, Outlook for Mac, Apple Mail, Apple Mail iOS, HEY Mail.
No support (15): Gmail, Gmail Android, Gmail iOS, Outlook 365, Outlook iOS, Outlook Android, Yahoo Mail, Yahoo Mail Android, Yahoo Mail iOS, Samsung Mail, Thunderbird, Proton Mail, AOL Mail, Fastmail, Superhuman. Plan fallbacks for these clients before relying on @import in production sends.
Fixes & Workarounds
Gmail
Unsupported"@import" is not supported in this email client.
Gmail Android
Unsupported"@import" is not supported in this email client.
Gmail iOS
Unsupported"@import" is not supported in this email client.
Outlook 365
Unsupported"@import" is not supported in this email client.
Outlook iOS
Unsupported"@import" is not supported in this email client.
Outlook Android
Unsupported"@import" is not supported in this email client.
Yahoo Mail
Unsupported"@import" is not supported in this email client.
Yahoo Mail Android
Unsupported"@import" is not supported in this email client.
Yahoo Mail iOS
Unsupported"@import" is not supported in this email client.
Samsung Mail
Unsupported"@import" is not supported in this email client.
Thunderbird
Unsupported"@import" is not supported in this email client.
Proton Mail
Unsupported"@import" is not supported in this email client.
AOL Mail
Unsupported"@import" is not supported in this email client.
Fastmail
Unsupported"@import" is not supported in this email client.
Superhuman
Unsupported"@import" is not supported in this email client.
Related Features
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Try Emailens FreeSupport data last updated Apr 27, 2026 · synced from caniemail.com via @emailens/engine.