What Is a Merge Tag?

A template holds the tags and the contact list holds the values, and substitution happens as each message is generated. The tag name has to match the field name exactly, which is why an imported list with a column called Company Name and a template expecting company produces a campaign of blanks.

Syntax varies by tool. Double braces are the most common convention, and other tools use single braces or percent-delimited names, so a template moved between platforms needs its tags rewritten rather than copied.

Depending on the tool, the recipient sees the raw placeholder, an empty gap, or a sentence with a hole in it. All three announce that the message was generated, and they do it in the copy that was supposed to prove the opposite.

Two mechanisms prevent it. A fallback value gives the tag something neutral to resolve to, and a pre-send check excludes contacts whose required fields are empty. The second is stronger, because a fallback keeps a weak message in the campaign while an exclusion removes it.

Any field on the record, including one that holds a full sentence. A custom field containing a researched observation about the recipient business lets the template read as though it was written for them, because the specific part of it was.

That reframes what the tag is for. The merge tag is only a delivery mechanism, and the value it inserts is where the personalisation actually lives, so the work belongs in the data rather than in the number of tags.