Certain types of links raise red flags for spam filters. 🚩
For this reason, as well as for compliance reasons, we do not allow certain types of links in ConvertKit emails.
We understand that most senders' intentions are innocent; however, the fact that these types of links have been heavily abused by spammers in the past means that the simple inclusion of them in your emails can harm your deliverability.
This is because spam filters will commonly associate these types of links with phishing attempts and other nefarious schemes.
The types of links that aren't allowed in ConvertKit emails include the following:
Many link shorteners
These links will not work within ConvertKit emails, even if they work when visited separately from your browser.
What should I do instead?
Instead of using a link shortener, link to the website directly. Transparency is key for good deliverability!