Definition
Merge tags (also called personalisation tags or custom fields) allow you to insert unique subscriber data into your email content dynamically. Instead of writing "Hello there," you write "Hello {{first_name}}," and each subscriber sees their own name.
Common Merge Tags
{{first_name}}— Subscriber's first name{{last_name}}— Subscriber's last name{{email}}— Subscriber's email address{{company}}— Subscriber's company name{{city}},{{country}}— Geographic data{{purchase_date}},{{product_name}}— Recent purchase data{{subscriber_since}}— Subscription anniversary{{unsubscribe_url}}— One-click unsubscribe link{{tracking_pixel}}— Open tracking pixel
Why It Matters
This matters because the choices you make here show up directly in your results. Instead of writing "Hello there," you write "Hello {{first_name}}," and each subscriber sees their own name. When this is handled well it supports engagement, delivery, and the trust subscribers place in your brand; when it is neglected, the effects tend to show up in declining performance and harder-to-fix problems further down the line.
Best Practices
- Start with the fundamentals of Email Merge Tag and build from a clear baseline, so later improvements are measurable rather than assumed.
- Keep Email Merge Tag consistent with how the rest of your email programme works, so no single initiative works against another.
- Review how Email Merge Tag is handled in your own data and adjust from what you see, rather than copying what another brand does.
- Test one change at a time and measure the effect before rolling it out more widely.
- Revisit your approach to Email Merge Tag regularly, because audience behaviour and inbox technology keep moving.
- Make sure the basics — relevance, timing, and honesty — are solid before chasing more advanced tactics.
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Frequently Asked Questions
Good practice here means handling Email Merge Tag in a way that is relevant, timely, and honest for your audience. Merge tags are dynamic placeholders in email templates that insert subscriber-specific data — first name, company, recent purchase, location — making each send feel individually crafted. Done well, it improves engagement and builds trust; done poorly, it creates friction that costs you results.
Because it touches the parts of email that drive outcomes: relevance, trust, and delivery. Small improvements compound, while repeated mistakes quietly erode the health of your programme.
The most common problems are treating Email Merge Tag as a one-off task, ignoring what the data says, and copying competitors without testing. All three lead to effort that does not translate into better results.
Compare the metrics it should influence — engagement, conversions, and deliverability — before and after you make changes. Trends over time matter far more than any single send.
It supports the same goal as the rest of your email programme: the right message to the right person at the right time. Aligned with segmentation and automation, it reinforces everything else rather than competing with it.