Preheader Text — The Hidden Conversion Booster in AcelleMail

Hidden preheader markup (for ensuring the right text appears even when inboxes auto-extract):

Most email templates include hidden preheader text at the top of the body:

<!-- Preheader (hidden visually; readable by inbox extractors) -->
<div style="display: none; max-height: 0; overflow: hidden;">
  Your preheader text here. Cannot exceed ~80 chars to avoid truncation.
</div>

Then add invisible filler to push the actual email content:

<div style="display: none; max-height: 0; overflow: hidden;">
  &zwnj;&nbsp; &zwnj;&nbsp; &zwnj;&nbsp; (etc — pad with zero-width-non-joiner)
</div>

The inbox extractor reads the first ~80 chars; recipients see only the visible email body.

AcelleMail's builder handles this automatically when you set the Preheader field. For raw HTML mode, add it yourself.

A/B testing preheaders:

If your subject lines are well-optimized, the next ROI lever is preheader testing:

1. New campaign → A/B test type
2. Variant A: "Sale ends tonight"
3. Variant B: "1,247 customers already saved"
4. Same subject + same body for both
5. Test on 20% sample; winner sends to 80%

Subject + preheader together = "what they see before opening." Combined optimization yields compound gains.

Per-segment preheader personalization:

For sophisticated segmentation, vary the preheader by audience tag:

Engaged segment:   "You're one of our most active subscribers"
At-risk segment:   "We've missed you — here's something to come back"
New segment:       "Welcome — here's the catch-up you've been waiting for"

In AcelleMail, this requires per-segment campaign splits (one campaign per segment with appropriate preheader). Some senders use dynamic Liquid in the preheader:

{% if 'vip' in subscriber.tags %}VIP early access — 24h before everyone else
{% else %}Spring sale starts now{% endif %}

But preheader display from receiving clients can be unpredictable with dynamic content — test before relying on this.

Preheader for transactional emails:

For password resets / receipts / order confirmations, the preheader should:

• Mention the action briefly ("Password reset link inside")
• NOT include sensitive details (not "Your code: 123456" — visible in inbox preview = security issue)
• NOT include the unsubscribe link (transactional emails don't have one)

Transactional subject: "Your password reset link"
Transactional preheader: "Click below; expires in 30 minutes"

Multi-language preheaders:

For multilingual senders:

{% if subscriber.locale == 'es' %}Última oportunidad: 20% de descuento
{% else %}Last chance: 20% off{% endif %}

Test in Spanish-speaking + English-speaking client previews to ensure render correctly.