Optimizing newsletter email size for deliverability
SOLVEHi! Looking for ideas, tips, best practices, and maybe a little commiseration here.
We suddenly started having our open rates tank for Gmail users and have narrowed the issue down to HTML file size. (For us the tipping point seems to be around 400KB, not 100KB as often suggested, but it's definitely happening.)
Check out how drastic the shift was! (this is open, click through, and click rates).
We're adjusting our templates accordingly, but in testing we tend to get caught by a big jump in HTML file size when HS turns the links into tracking links.
It's hard to make this particular email smaller/shorter because it's a member newsletter with multiple pieces of content, not a promotional email with a single CTA. This is why opens are one of our most important metrics for this email - even if a member doesn't click, reading the newsletter is a connection to and reminder of the value of their membership. We also sell ads, both banner and text ads, within this newsletter, and could have anywhere from 1 to 4 ads in the newsletter depending what we've sold for that issue.
We are already working on simplifying our template - getting rid of extraneous design elements, line breaks, switching some buttons to text links, etc.
Has anyone figured out a way to make the links shorter? We'll be keeping an eye on the file size and it will be okay but then we'll send a test through HubSpot and it'll jump in size because all the tracking links are so long.
Any help or commiseration would be appreciated, especially from others who send newsletter type emails.
1 Accepted solution
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Optimizing newsletter email size for deliverability
SOLVEHi @karenkaz this is really interesting, thank you for sharing so much detail about the size of the emails relative to performance.
One option would be to remove the HubSpot CTAs (thereby removing the tracking code) and instead rely on the email click data to see who clicked, adding them to lists, workflows, etc. to improve reporting.
You can also generate tracking links with UTM parameters that while make the URL a bit longer, but don't function in the same way as the HubSpot tracking code.
The UTM parameters will allow your click data to show as "Other Campaigns" and then breakdown based on the UTM parameters you include.
It might be worth testing these options out to see if there's an improvement.
replies and solutions prior to May 2025 were as a member of the community and are not an official response as an employee of HubSpot
Optimizing newsletter email size for deliverability
SOLVEHi @karenkaz this is really interesting, thank you for sharing so much detail about the size of the emails relative to performance.
One option would be to remove the HubSpot CTAs (thereby removing the tracking code) and instead rely on the email click data to see who clicked, adding them to lists, workflows, etc. to improve reporting.
You can also generate tracking links with UTM parameters that while make the URL a bit longer, but don't function in the same way as the HubSpot tracking code.
The UTM parameters will allow your click data to show as "Other Campaigns" and then breakdown based on the UTM parameters you include.
It might be worth testing these options out to see if there's an improvement.
replies and solutions prior to May 2025 were as a member of the community and are not an official response as an employee of HubSpot
