CSS Properties

text-underline-position

CSS property · 6 supported, 4 partial, 3 unsupported across 15 clients

Client Support

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

Client-by-client behaviour for text-underline-position

Fully supports text-underline-position (6): Gmail, Gmail Android, Outlook 365, Outlook Android, Samsung Mail, Thunderbird.

Partial support (4): Gmail iOS, Outlook iOS, Apple Mail, Apple Mail iOS. Expect rendering quirks unique to each engine — partial support typically means a subset of values, an ignored shorthand, or sanitizer-specific rewrites.

No support (3): Outlook (New), Outlook Classic, Yahoo Mail. Plan fallbacks for these clients before relying on text-underline-position in production sends.

Behaviour unverified in: HEY Mail, Superhuman.