Definition
Conditional tables use MSO conditionals to deliver different table markup to Outlook, which renders with the Word engine and needs bespoke code.
Conditional comments let you keep the Outlook version aligned with the modern-client version.
Conditional tables are how Outlook gets the layout it needs without breaking other clients. MSO conditionals wrap Outlook-specific markup, which other clients ignore. Keeping both versions aligned and documented prevents drift.
How They Work
Outlook-only markup is wrapped in conditional comment blocks.
Modern clients treat the conditionals as comments and ignore them.
Why It Matters
Conditional tables are how Outlook gets the layout it needs without breaking other clients. Understanding them is core to professional email development.
Best Practices
- Use conditional comment blocks for Outlook-specific tables.
- Keep the Outlook and modern-client versions visually aligned.
- Comment the intent so maintainers understand why both tables exist.
- Test in Outlook and modern clients.
- Keep conditional blocks tidy.
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Frequently Asked Questions
HTML comments Outlook reads to include or exclude markup. Conditional tables are how Outlook gets the layout it needs without breaking other clients.
No, they treat them as comments and ignore them. MSO conditionals wrap Outlook-specific markup, which other clients ignore.
They add code, so document them and test after editing. Keeping both versions aligned and documented prevents drift.
It renders with the Word engine, which ignores modern CSS. Conditional tables are how Outlook gets the layout it needs without breaking other clients.
Technically yes, but they are mainly used for Outlook. MSO conditionals wrap Outlook-specific markup, which other clients ignore.