Hello @Match2490,

Welcome to the Klaviyo Community!

It’s actually not uncommon for emails to look a bit off in Outlook. Instead of this being a responsiveness issue, this is actually an industry-wide roadblock stemming from how Outlook renders emails. This is further explained in our My email looks different when viewed in Microsoft Outlook Help Center article in case you didn’t get a chance to take a look at it. 

Ever since 2007, Microsoft/Outlooked switched from using Internet Explorer to render HTML to Microsoft Word which causes some known issues such as the following:

• No support for background images in divs and table cells
• No support for CSS float or position
• No support for text shadow
• Poor support for padding and margin
• Poor support for CSS width and height
• Problems with nested elements background colors 

Litmus, an email preview software we highly recommend has a great blog article they written providing some tricks in combatting these difference: Outlook Email Rendering Issues and How to Solve Them.

Ultimately, there isn’t too much you can do to avoid these differences. This would be one of those aspects you’ll simply need to be aware of when sending your emails. I’ve seen success from members who segment out their Outlook/Microsoft inbox providers for a separate email sends that has been optimized for Outlook inboxes to offer a more seamless email. For this reason, we oftentimes suggest using Litmus, Email on Acid, or your choice of preview tool to help see how emails will look in different inbox providers and through different devices and mediums. 

I hope this helps!

David