Anchor links can be useful if you send bilingual emails and want to link to the part of the email where the content of the secondary language starts.
Email too long?
For monolingual emails if using anchor links is necessary that's typically an indication that the email itself is too long. Emails are meant to be fairly short with "teaser" content to get the attention of recipients and links to "read more" or other actions to landing pages and websites. This approach has the benefit of tracking clicks from the email to gauge engagement level for each article / section within the email. There is no way to track if long emails with no "read more" or other links were read fully or partially and which part of the email your recipients read or didn't read.
If you must use anchor links here's how to add them:
Step 1: add an anchor and give it a name
Step 2: link to the anchor from any link from your email by typing #anchorname as the link:
Anchor links support across email clients
Note that anchor links aren't supported by every email client; notably they won't work in the native email app for iPhone IOS8 and newer.
A workaround is to link to the anchor in the online version of your email. That way when the anchor link is clicked, readers are taken to their web browser where anchor links (# hashtag links) are widely supported. To link to the anchor link in the online version of your email use this as the target URL for the link: