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Writing Templates4 min read

Personalize with merge tags

Use {first_name}, {company}, and any custom column from your sheet to make every email feel one-to-one.

Merge tags let you insert dynamic values into your email template — values that are replaced with each recipient's actual data before the email sends. A template with {first_name} in the subject line becomes 'Hey Sarah,' for one recipient and 'Hey Marcus,' for another.

Standard merge tags

These tags are available in every campaign, as long as your contact list includes the corresponding data:

  • {first_name} — the recipient's first name
  • {last_name} — the recipient's last name
  • {email} — the recipient's email address
  • {company} — the company name from your contact list
  • {unsubscribe_url} — a one-click unsubscribe link (required for CAN-SPAM compliance in commercial email)

Custom merge tags from your Sheet or CSV

Every column in your Google Sheet or CSV beyond the standard ones becomes a custom merge tag. Import a Sheet with a 'Job Title' column and {Job Title} becomes available in your template. Custom tags appear as purple chips in the Personalize section of the Template tab.

CMass Template tab showing merge tag chips: first_name, last_name, email, company, unsubscribe_url
Click any merge tag chip to insert it at your cursor position.

Using merge tags

There are two ways to insert a merge tag:

  • Click any tag chip in the Personalize section — it's inserted at your cursor position in the subject or body
  • Type { in the subject or body — CMass shows an autocomplete dropdown with all available tags. Keep typing to filter, then press Enter or click to insert

Fallback values

If a recipient doesn't have a value for a merge tag — for example, their first name is missing — CMass uses a fallback. The default fallback for {first_name} when no first name is available is the part of the email address before the @. So john.smith@acme.com becomes 'john.smith'.

Write better subject lines: Subject lines with {first_name} personalization typically get 10–20% higher open rates vs. generic subjects. Keep subject lines under 50 characters so they don't get cut off on mobile.

Preview before sending

Click the Preview button at the bottom of the panel to see your email with real values substituted — you can browse each recipient to catch any merge tag issues before launch.

The unsubscribe tag

If you're sending commercial or marketing email, you must include an unsubscribe mechanism under CAN-SPAM and GDPR. Add {unsubscribe_url} anywhere in your email body — CMass replaces it with a unique one-click unsubscribe link for each recipient. When someone clicks it, they're immediately removed from future campaigns.

💡 CAN-SPAM requires a physical mailing address in commercial emails in addition to an unsubscribe link. You can add your address to your email signature or in the footer of the email body.

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