topic Re: HubSpot Email Signature - Outlook in Sales Email

HubSpot Email Signature - Outlook

alexagatiss — Thu, 29 Jan 2026 17:37:36 GMT

Hi there, how can we recreate our Outlook signature in HubSpot? I have been putting it into HTML code but for many on our sales team, there is an error and it says the image is too large, even though it has been resized to be a very small file. What are the options to create the signature? We want it to be seamless so that signature looks consistent. How are most people doing this? We only have a tiny element that is like less than 40x40px so I am assuming if we just included a screenshot image of the signature in the HubSpot signature box that would also have issues? Has anyone successfully been able to have a consistent email signature across Outlook and HubSpot? When I have reached out to HubSpot support on this issue they have been unwilling to help since it is "custom HTML?"

Re: HubSpot Email Signature - Outlook

RubenBurdin — Thu, 29 Jan 2026 21:17:03 GMT

Hi @alexagatiss , This is one of those annoyingly common issues that comes down to how HubSpot handles images in signatures versus how Outlook does it. The "image too large" error usually isnt about file size but about how the image is being referenced in the HTML.

The most reliable fix I've seen is to host your signature images externally rather than embedding them. Upload the image to HubSpot's file manager (or any public CDN) and then reference it with a full URL in your HTML like <img src="https://yourhostedimage.com/signature.png ">. HubSpot's native signature editor sometimes struggles with base64 encoded images or images copied directly from Outlook. Theres some guidance on setting up signatures here (https://knowledge.hubspot.com/account-management/add-an-email-signature-in-the-crm )

For the 40x40px element you mentioned, make sure its saved as PNG or JPG under 100kb and hosted externally. Also double check your HTML doesnt have any Outlook specific conditional comments or VML code, those tend to break things in HubSpot. One workaround some teams use is creating the signature fresh in HubSpot's visual editor rather than porting Outlook HTML, then replicating that design back into Outlook. Disclosure: This answer comes from my own experience and was lightly rephrased with AI to improve readability.

Hope you get this sorted!

Re: HubSpot Email Signature - Outlook

alexagatiss — Thu, 29 Jan 2026 21:19:42 GMT

Thank you, however the image has already been uploaded to HubSpot's file manager and the HTML code references the URL, but I am still running into this error. Do you have any other suggestions?

Re: HubSpot Email Signature - Outlook

RubenBurdin — Thu, 29 Jan 2026 21:27:31 GMT

Thats frustrating. A few more things to try:
Can you open the image URL directly in an incognito window? Sometimes HubSpot file manager URLs have permission issues that block rendering. Also try stripping the HTML down to just <img src="yoururl" width="40" height="40"> with nothing else, Outlook exports often include extra markup that HubSpot doesnt like.
What file format is the image? PNG and JPG work best, if its WEBP or SVG try converting it. If you can share the HTML snippet (with sensitive info removed) I can take a look and see if something jumps out.

Re: HubSpot Email Signature - Outlook

Victor_Becerra — Thu, 29 Jan 2026 21:35:20 GMT

Hey there @alexagatiss thank you for your post!

I want to share a couple of community threads that have similar issues as yours and can help you give more context:
https://community.hubspot.com/t5/Tickets-Conversations/Email-Signature-This-image-is-too-large-to-display/td-p/1144485

https://community.hubspot.com/t5/Sales-Email/HTML-Email-Signature-in-HubSpot/m-p/1105229

I also want to tag a few Subject manager experts from our community who can help us out: Hey there @JTolley @TomM2 @Shubham_Sharma I hope you're having a great week! Any ideas you can share with us here?

Thanks

Victor