Personalization tags

A personalization tag is a placeholder you put in a subject line or an email body that is replaced with that contact's own data at send time. This page covers inserting tags, setting a fallback for contacts who are missing a value, and testing that the fallback works before you send to anybody.

How tags work#

Every contact has fields: their email address, plus whatever else you collect, such as first name, company, city or plan. Those fields are defined under Fields and are covered in Custom fields.

A tag names one of those fields. When the campaign goes out, each recipient's copy has the tag swapped for their own value. One thousand recipients get one thousand slightly different emails from one piece of content.

Insert tags using the editor's personalization control rather than typing them by hand. The control lists the fields that exist on the list you are sending to, and it writes the tag in the exact form the sender expects. Typing a tag from memory is how you end up sending a literal placeholder to your whole list.

Tags work in the body and in the subject line. Personalizing the subject line is where most of the value is, and also where most of the damage is if it goes wrong, because a broken subject line is visible in the inbox without anyone opening the message.

Fallbacks#

A fallback is the text used when a contact has no value for that field. Set one on every tag. Not most tags. Every tag.

Lists are never as complete as you think. Contacts who arrived through an import, an API call or a two-field signup form frequently have an email address and nothing else. If you have 8,000 contacts and 600 of them are missing a first name, a tag without a fallback ships a visibly broken email to 600 people.

A subject line that fails

Take this subject line, with a tag for the first name field:

Hi FIRST_NAME, your September picks are ready

For a contact whose first name is Dana, it renders as intended:

Hi Dana, your September picks are ready

For a contact with no first name stored, and no fallback set, the tag resolves to nothing at all:

Hi , your September picks are ready

That is a space before a comma, sitting in the inbox, at the top of the message list. It reads as broken software, which is exactly what it is. Readers who were on the fence about your email now have a reason.

Now set the fallback to there:

Hi there, your September picks are ready

That is a normal sentence. Nobody can tell it was a fallback.

Choosing a fallback

The test is whether the sentence still reads naturally with the fallback substituted in. Say the whole line out loud both ways.

When no fallback reads naturally, that is a signal the sentence is wrong, not the fallback. Rewrite it so the personalization is optional rather than load-bearing. "The best cafes in Portland" has no graceful fallback. "The best cafes near you" needs no tag at all.

Testing that fallbacks render#

Confirming that a tag works for a contact who has the data proves nothing. You have to prove the empty case.

If something goes wrong#

The tag sent as literal text. The tag was typed rather than inserted, or it names a field that does not exist on the list you sent to. Insert it again from the editor's personalization control.

The tag is empty for some contacts and correct for others. That is a data problem, not a tag problem. Some contacts have no value for that field. Set a fallback, and if the field matters, look at where those contacts came from. An import that skipped a column or a signup form that never asked for the field are the usual causes.

Names arrive in the wrong case. Values render exactly as they are stored, so dana from a signup form arrives as dana. Fix the data on import rather than in the email.

The same tag works in the body but not the subject line. Check that the subject line tag has its own fallback. A fallback set on one instance of a tag does not apply to another instance elsewhere in the campaign.