SharePoint News Email “Content too large” issue – size limit clarification

Hi,

We are currently trying to send a SharePoint News post via email and encountering the following error:

“The contents of this page are too big to send in email.”

We performed testing to understand the limitation and observed the following:

• Full newsletter (~5.29 MB) → ❌ Error
• Pages 1–12 (~3.11 MB) → ❌ Error
• Pages 1–11 (~2.80 MB) → ✅ Works
• Slight increase (~2.90 MB) → ❌ Error again

✅ Based on testing:

• Practical threshold seems around ~2.7–2.8 MB
• Above this, email rendering fails

❓ Questions:

1. Is there a documented maximum size limit for SharePoint News email content?
2. Is the limit based on:
   • Total content size after rendering?
   • Image count/size?
3. Can this limit be configured or increased?
4. What are the recommended best practices for image-heavy newsletters?

✅ Current understanding:

• It appears that the limitation is due to HTML email rendering size rather than just file size

Any clarification or official guidance would be appreciated.

Thanks.