Latest / The Email Marketing Podcast with Fexingo: Newsletters, Open Rates, and Subscriber Growth / Why Your Preheader Text Is an Email Marketing Superpower
Transcript
- Lucas: You spend an hour on a subject line. Maybe two. You A-B test it, you sleep on it, you run it through a power words checklist. And then, right below that subject line, in the same inbox preview — most email clients show about ninety characters of preheader text — and most people just let the email client auto-populate the first sentence of the body. Luna: And that auto-populated sentence is usually something like 'Having trouble viewing this email?' or 'View this email in your browser.' It's basically dead space. Lucas: Exactly. You're giving away prime real estate. The preheader — sometimes called the Johnson Box or the preview text — is the second line a subscriber sees before they decide to open. And a 2025 study from Campaign Monitor found that emails with a custom, optimized preheader saw a 28 percent higher open rate compared to emails with no preheader or a default one. Luna: Twenty-eight percent is huge. That's like rewriting your subject line for free. So what makes a good preheader? Lucas: First rule: it should not repeat the subject line. If your subject line is 'Our biggest sale of the year,' the preheader should not say 'Our biggest sale of the year — shop now.' That's redundant. Instead, it should complement the subject, add a new piece of information, or create a curiosity gap. Luna: Right — give me a reason to open, not just a longer version of the same headline. Lucas: Example from Bonobos. Subject line: 'You asked for more colors.' Preheader: 'We delivered. 12 new shades of our bestselling chino, available for 48 hours.' The subject creates curiosity — what colors? The preheader answers the question but also adds urgency. Open rate on that campaign was 42 percent, well above their average of 33 percent. Luna: They didn't just say 'shop now.' They gave the number: 12 new shades. Specificity works. Lucas: Warby Parker does something similar. Their subject line: 'Your new glasses are waiting.' Preheader: 'Five frames, one try-on kit, zero commitment. Shipping is free.' In three short phrases, they've answered every objection: selection, convenience, cost. Luna: And they front-loaded the value. 'Five frames' — you know exactly what you're getting. Lucas: The second rule: pass the glance test. Most people check email on mobile. The preheader is truncated after about fifty to ninety characters depending on the device. So the first forty characters of your preheader need to carry the weight. If that part is filler, you lose them. Luna: What's an example of failing the glance test? Lucas: I'll pick on a DTC mattress company — let's call them SleepWell. Subject line: 'Wake up refreshed.' Preheader: 'This email contains information about our latest mattress model and a special offer for subscribers like you.' That's fifty-three characters of nothing. The first forty characters are 'This email contains information about' — who cares? They should have written: 'New mattress model — $200 off for subscribers. Ends Friday.' Luna: Night and day. One tells me what to expect, the other tells me to expect something. Lucas: Third rule: use the preheader to overcome a subject-line weakness. If your subject line is short or cryptic — which some brands use deliberately to create curiosity — the preheader has to give enough context to make the open feel safe. Luna: Safe meaning the subscriber knows what they're clicking on and won't be misled. Lucas: Yes. Example: subject line 'Your account.' That's vague — could be a security alert, a password reset, or a marketing blast. The preheader saves it: 'Your monthly statement is ready. View your March transactions.' Now it's specific and useful. Open rate on that type of email is usually around 55 percent, versus maybe 20 percent if the preheader is just 'Having trouble viewing?' Luna: So the preheader is basically the insurance policy for your subject line. It fills in the gaps. Lucas: Exactly. And the fourth rule — and this is the one most marketers get wrong — the preheader should not be an afterthought. It should be written at the same time as the subject line, not pulled from the body text. If you write the body first and let the email client grab the first sentence, you're leaving money on the table. Luna: Let's talk about length. Is there a sweet spot? Lucas: Campaign Monitor's data suggests the optimal preheader length is between forty and sixty characters. That's enough to say something meaningful without being truncated. But it also depends on email client. Apple Mail shows more characters than Gmail's mobile app. So I'd say: write for the smallest window, which is about fifty characters on an iPhone Mail preview. If your first fifty characters are compelling, you've won. Luna: And if you're a B2B brand? Does the same advice apply? Lucas: Yes, but the tone shifts. B2B subject lines are often more direct: 'Q1 report is here.' The preheader can add a key data point: 'Revenue up 12 percent, customer churn down 3 points.' That gives the recipient a reason to open and forward to their team. I've seen a B2B SaaS company increase click-through rates by 18 percent just by adding a preheader that teased the report's top finding. Luna: So the preheader is doing double duty: it gets the open, and it sets the expectation for what's inside. Lucas: Correct. And the fifth rule — use the preheader for urgency and scarcity if the subject line didn't. Subject line: 'Flash sale starts now.' Preheader: 'First 100 orders get free shipping. Code: FAST100.' Now the preheader is a call to action. You've given the subscriber a reason to open immediately. Luna: That's smart — it turns the preheader into a mini incentive. Lucas: One more thing: the preheader is also a chance to preview the offer format. If your email is a newsletter, the preheader can be a bullet list of topics: 'Today: the CPI report, a deep dive on treasury yields, and why copper is suddenly hot.' That tells the reader exactly what they'll get, and it serves as a table of contents. Luna: I've seen that in the Morning Brew emails. Their preheader often lists three topics, and it works because I know what I'm clicking into. Lucas: Exactly. So to recap the five rules: one, don't repeat the subject line; two, pass the glance test with the first forty characters; three, use the preheader to give context to a cryptic subject; four, write it at the same time as the subject line, not after; five, add urgency or a clear benefit if the subject line didn't. Luna: This is one of those high-leverage changes. It costs nothing, takes maybe ten minutes, and can lift open rates by 20 to 30 percent. That's huge for any email program. Lucas: Honestly, if this episode gave you one concrete tweak you'll use in your next email — that's the whole point. And if it was worth a coffee to you, there's a link on our show page: buy me a coffee dot com slash fexingo. Keeps the show ad-free and helps us dig into these nitty-gritty topics. Luna: Yeah, it's a small way to say this kind of detail-oriented content matters. And it does — we read every message. Lucas: So before you hit send on your next campaign, take a look at that preview text. Ask yourself: does this make me want to open? If you're not sure, rewrite it. Your open rate will thank you. Luna: And if you've got a preheader tip or a horror story, we'd love to hear it. Reach out to us on the show's social feeds or through the website. We might feature your example in a future episode. Lucas: Alright, that's our ten. Go check your preheaders. We'll be back next week with another email marketing deep dive.