Your branded HTML email with the custom header, the logo in the right corner, and the perfectly proportioned CTA button is probably underperforming an email that looks like it was written in five minutes with no design input at all.
This is not a theory. The data on plain text performance in B2B is consistent enough that it should be changing how tech marketers think about their nurture sequences and outreach cadences. It largely has not altered messaging strategy, because it runs against every instinct that comes from investing in brand and design systems.
Plain text emails outperform GIF and image-heavy HTML emails, receiving 42% more clicks than HTML and 51% more clicks than image-heavy formats, according to HubSpot research across more than a thousand campaigns. In every industry studied, plain text emails show 21% higher click-to-open rates and 17% higher click-through rates than HTML emails.
The conversion numbers are equally stark. Existing customers converted at a rate of 60% with plain text emails compared to a significantly lower rate with polished formats. For cold outreach in B2B, plain text emails also show 23% higher open rates according to deliverability research published in 2026.
It is worth noting that raw open rates have become a less reliable metric since Apple Mail Privacy Protection began pre-loading tracking pixels on Apple devices, which now account for more than half of all email opens. Click-through rate and reply rate are considerably more meaningful benchmarks for B2B outreach.
Email is, at its core, a person-to-person communication channel. HubSpot's research framing is useful here: email feels like a one-to-one interaction, and plain text preserves that feeling in a way that designed templates do not.
When a recipient opens a beautifully branded HTML email, they immediately recognize it as a marketing communication. They are in a different mental mode than when they open what looks like a personal note from someone. Their guard is up slightly, and they are scanning, not reading.
A plain text email from a name they recognize (or are curious about) reads as a direct conversation. The absence of design signals authenticity: it suggests that a human composed this message specifically for them, even if they know rationally that it went to a list.
There is also a practical deliverability component. Modern spam filters treat plain text and HTML emails differently. Plain text emails signal a personal, one-to-one message, which means they are less likely to be filtered, pre-categorized into promotional folders, or deprioritized in busy inboxes. The less your email looks like a newsletter, the more likely it is to land in the primary inbox.
This is not a case for abandoning design entirely. HTML emails serve a genuine purpose for certain use cases. The question is whether you are choosing the right format for the right context, or defaulting to polished because it looks more professional without considering what professional actually means to the recipient.
The test is simple: is this email trying to look like a one-to-one conversation, or is it functioning as a publication? If it is trying to look like a conversation, strip the design.
Most B2B tech companies run nurture sequences that follow a consistent HTML format from top to bottom. The better approach is to layer in format variation based on where the contact is in the journey and what action you are trying to drive.
Early-stage nurture, where someone has downloaded a resource or attended a webinar, can sustain a designed format because the relationship is clearly marketing at this point. The recipient knows they are in a sequence.
As contacts move further down the funnel and you are trying to move them toward a conversation, transitioning to plain text from a named person on your team increases response rates significantly. The shift in format signals a shift in intent from broadcasting to engaging.
For re-engagement of contacts who have gone cold, a plain text email from a named person is consistently the highest-performing format. It reads as a genuine human follow-up rather than an automated sequence.
The format decision is only half the equation. A plain text email that lands in the right inbox still needs messaging that earns a reply, and that is where most campaigns lose the gains they made on deliverability. We work with you on the messaging strategy behind their outreach sequences, including how to write plain text emails that read as genuinely personal without sacrificing consistency at scale. If your current nurture or outbound cadence is not converting the way the format shift alone should be delivering, that is worth a conversation.
Not in the contexts where they are appropriate. A plain text follow-up from a named sales or customer success rep reads as attentive and personal, not unprofessional.
Yes, and this is actually the recommended approach. Format variation within a sequence, transitioning from designed early-stage content to plain text later-stage outreach, performs better than maintaining the same format throughout.
Focus on reply rate and click-through rate. These metrics are not distorted by Apple Mail Privacy Protection and give you a clearer picture of actual engagement than open rates do.