Merge Tags & Personalization

Merge tags let you personalize every email for each prospect automatically.

Built-in Tags:

LinkedIn-Specific Tags (in LinkedIn campaigns):

Sender Tags:

Opt-out Tag:

Custom Fields:
When importing prospects via CSV, any column not matching a built-in field becomes a custom field. For example, a CSV column 'department' maps to custom:department. Five spellings all resolve to the same value, so a template pasted in from another tool keeps working: {{custom.department}}, {{custom_department}}, {{custom_fields.department}}, {{customFields.department}}, and the bare shorthand {{department}}. The {{custom.department}} form is recommended and is what the variable picker inserts.

Custom Fields in Subject Lines:
Custom fields from your CSV work everywhere — including the subject line. If you import a CSV with a custom:subject_line column, you can set your entire subject to {{custom.subject_line}} or {{subject_line}}. For fully pre-written emails, your subject line could be just {{custom.subject_line | default: 'Quick question'}} — each prospect gets their own unique subject.

Fallback / Default Values (two ways to write them):
A fallback is the value used when a field is empty or missing for a prospect — perfect for a column that's only partly filled in. WarmySender supports two ways to write it, and they do exactly the same thing, so use whichever reads more naturally to you:

1) Long form (the classic way):

2) Short form with a double pipe (||):

More examples you can copy and paste:

Good to know about the short form:

Tags We Don't Recognise (and placeholders from other tools):
A tag that matches no built-in field and no custom field sends as EMPTY — it is never printed literally in your email. Before you launch, the pre-launch check lists every unrecognised tag by name so you can fix or remove it, and it also spots square-bracket placeholders carried over from other tools ([company], [first name], [[FirstName]]) and offers a one-click fix that converts each to the matching WarmySender tag. Square brackets are not merge tags here, so left alone they go out exactly as typed — always accept the fix or edit them yourself.

Best Practices:

Related guides in Campaigns

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