CSS Properties

overflow

CSS property · 4 supported, 15 partial, 2 unsupported across 21 clients

Client Support

Client	Category	Engine	Support
Gmail	webmail	Gmail Web	Partial
Gmail Android	mobile	Gmail Mobile	Partial
Gmail iOS	mobile	Gmail Mobile	Partial
Outlook 365	webmail	Outlook Web	Partial
Outlook (New)	desktop	Outlook Web	Unsupported
Outlook Classic	desktop	Microsoft Word	Unsupported
Outlook iOS	mobile	Outlook Mobile	Partial
Outlook Android	mobile	Outlook Mobile	Partial
Outlook for Mac	desktop	WebKit	Partial
Apple Mail	desktop	WebKit	Partial
Apple Mail iOS	mobile	WebKit	Partial
Yahoo Mail	webmail	Yahoo	Partial
Yahoo Mail Android	mobile	Yahoo	Partial
Yahoo Mail iOS	mobile	Yahoo	Partial
Samsung Mail	mobile	Samsung	Partial
Thunderbird	desktop	Gecko	Supported
HEY Mail	webmail	WebKit	Supported
Proton Mail	webmail	Proton	Partial
AOL Mail	webmail	AOL	Partial
Fastmail	webmail	Fastmail	Supported
Superhuman	desktop	Blink	Supported

Client-by-client behaviour for overflow

Fully supports overflow (4): Thunderbird, HEY Mail, Fastmail, Superhuman.

Partial support (15): Gmail, Gmail Android, Gmail iOS, Outlook 365, Outlook iOS, Outlook Android, Outlook for Mac, Apple Mail, Apple Mail iOS, Yahoo Mail, Yahoo Mail Android, Yahoo Mail iOS, Samsung Mail, Proton Mail, AOL Mail. Expect rendering quirks unique to each engine. Partial support typically means a subset of values, an ignored shorthand, or sanitizer-specific rewrites.

No support (2): Outlook (New), Outlook Classic. Plan fallbacks for these clients before relying on overflow in production sends.

Fixes & Workarounds

Outlook (New)

Unsupported

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Outlook Classic

Unsupported

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Gmail

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Gmail Android

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Gmail iOS

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Outlook 365

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Outlook iOS

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Outlook Android

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Outlook for Mac

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Apple Mail

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Apple Mail iOS

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Yahoo Mail

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Yahoo Mail Android

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Yahoo Mail iOS

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Samsung Mail

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Proton Mail

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

AOL Mail

Partial

Content will always be visible. Design accordingly.

Before

<div style="max-height: 200px; overflow: hidden;">
  Long content that gets clipped...
</div>

After

<!-- Show full content, or truncate server-side -->
<div style="max-height: 200px;">
  Shortened content that fits...
  <a href="https://example.com/full">Read more</a>
</div>

Content will always be visible — design for full content display

Production guidance for overflow

overflow is a CSS property. Across the email client matrix, 4 of 15 tracked clients support it fully, 15 only partially, and 2 not at all. The clients most likely to require a workaround for this feature are Outlook (New), Outlook Classic, Gmail. Each of them needs a tailored fallback. See the per-client examples above for the specific code fix Emailens recommends.

When in doubt, ship a baseline that renders without overflow and treat it as progressive enhancement on clients where support is verified. Emailens automatically detects cross-client divergence on this feature when you preview an email, so you can see exactly which template paths break before a campaign goes out.

Related Features

!important accent-color align-items animation aspect-ratio backdrop-filter background background-blend-mode

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Support data last updated Apr 27, 2026 · synced from caniemail.com via @emailens/engine.