Email remains one of the channels with the highest marketing ROI. However, the days of sending the same email to everyone are long gone. Covers all email marketing technologies for 2026, including how to properly use HubSpot's bulk delivery, automatic delivery, and AI-optimized emails, subject line design, delivery timing, and delivery rate management.
HubSpot's email function can be divided into three types depending on when, to whom, and how to send the email. The correct use of these three types is the starting point for designing your entire email marketing.
| kinds | send trigger | degree of personalization | Main uses | Creation location |
|---|---|---|---|---|
| Bulk distribution | Manual / Reservation date and time | △ (token only) | Newsletter/Announcement | Marketing → Email |
| automatic delivery | workflow trigger | △～○ (smart content) | Nurturing onboarding | Created within a workflow |
| AI-Powered Email | AI determines the best timing | ◎ (per contact) | High engagement appeal | Marketing → Email → AI |
The criteria for judgment are simple—“Do we need to reach everyone at the same time?”. If there is, use bulk distribution, if not, use automatic distribution (workflow). It is appropriate to distribute monthly newsletters all at once, and automatically distribute follow-up after downloading materials. In many cases, the majority of initiatives can be moved to automated delivery;The workload of the person in charge is significantly reduced.。
No matter how good the main text is,It's meaningless if the subject doesn't get people to open it.. First, use the subject line/preheader to get an open page, and then use the body text to encourage action. It is important to keep this two-tiered structure in mind when designing.
| pattern | example | effect | Points to note |
|---|---|---|---|
| Numbers/specificity | “Why the number of business negotiations increased by 2.4 times in 3 months after introducing MA” | Open rate ↑↑ | Use actual data for numbers (exaggeration undermines credibility) |
| question form | “Are you able to use MA effectively in your company?” | Open rate ↑ | The content must be something that readers feel is their own. |
| personalized | “[Mr. Yamada] Please join us for this week’s webinar.” | Open rate ↑↑ | Don't forget to set the fallback value |
| Urgency/scarcity | “3 seats left — free webinar deadline tomorrow” | Click rate ↑↑ | If it is not really rare, it will have the opposite effect and loss of trust. |
| conversational tone | “Actually, there are many people in charge who are worried about this kind of thing.” | Open rate △ | More effective in B2C/casual industries than B2B |
| spam word | “[Urgent] Give everything away for free now!!” | Reach rate ↓↓ | High risk of getting caught in spam filters |
Even for the same email, the open rate can vary by 2 to 3 times depending on when it is sent. Planning when to send is just as important as designing the subject line.
Heatmaps are just a guide.The optimal time varies greatly depending on the industry, persona, and list characteristics.. It is more important to continually verify your company's data through A/B testing than to generalize that "Tuesday at 10 o'clock is better."
AI analyzes each contact's past email opening history and sends emails individually at "times when this contact is most likely to open emails." Even in bulk distribution, messages are sent at different times to each recipient.
Just select "Smart Send Time" in the "Send Time" setting on the email creation screen. Available for Professional and above. Contacts without sufficient open history will be sent at the default time.
HubSpot's internal data shows that emails using Smart Send tend to have 6-14% higher average open rates than those sent at fixed times. The larger the list, the more effective it will be.
Not suitable for highly urgent emails that need to be sent within 24 hours. Using smart send times may result in a delivery lag of up to 24-48 hours.
Full-scale operation began in the second half of 2025 AI-Powered Email goes beyond traditional “segment-based smart content”.Complete individual optimization for each contactIt is a function that realizes. AI learns and optimizes the subject line, body text, CTA, and sending timing.
From the end of 2025 to 2026 Journey Automation(the ability for AI to autonomously optimize the entire customer journey) is being integrated into Marketing Hub. AI-Powered Email is positioned as part of this,Beyond optimizing individual emails, AI determines “what channel to deliver, what to deliver, and when to deliver” throughout the journey.is evolving in this direction.
No matter how well you design the subject line and body text,If the email doesn't arrive in your inbox, it's all for nothing.Become. Managing deliverability may seem unremarkable, but it is the lifeblood of email marketing.
From February 2024, Google and Yahoo will require bulk senders (more than 5,000 messages per day) to set up SPF, DKIM, and DMARC.required requirementIt became. If not configured, emails will be routed to your spam folder or rejected entirely.Be sure to complete your domain verification setup before you start sending emails with HubSpotis an absolute condition as of 2026. How to set Settings → Marketing → Email → Authentication You can check from
Don't just send and call it a day - this is the starting point for improving your email marketing. With HubSpot's email analysis screen, you can check the results in real time immediately after sending them and use them for next steps.
Since Apple introduced Mail Privacy Protection (MPP) in 2021, the Mail app on iOS and macOS hasOpen rate recorded as “false 100%”The number of cases is increasing. For this reason, from the “open rate alone” CTOR (click-open rate) and actual conversion rateThere is a shift towards emphasizing this as a major KPI. You can also set filters that take into account the influence of MPP on the HubSpot analysis screen.
| symptoms | causal hypothesis | improvement action |
|---|---|---|
| Low open rate (15% or less) | The subject line is not clear / There is little trust in the sender's name / Too many emails are sent | A/B test subject line / Change sender name to personal name / Reduce delivery frequency |
| Low CTR (less than 1%) | The body text and offer don’t mesh well / The CTA doesn’t stand out / There are too many links | Focus on one CTA per email / Improve CTA text and colors / Check consistency of text and offer |
| CTOR is low (below 10%) | There is a mismatch between the expectations after opening the package and the content of the text / The text is too long / The value of the CTA is weak | Improve consistency between subject line and body text / Make body text concise / Change CTA wording to benefit appeal |
| High unsubscribe rate (over 0.5%) | Delivery is too frequent / content is no longer relevant / content is not what you expected | Review of distribution frequency / Review of segments (are you sending to unrelated people?) / Conduct a survey on reasons for discontinuation of distribution |
Use bulk distribution (all at the same time), automatic distribution (workflow trigger), and AI-powered email (optimization by contact) depending on the purpose.
Numbers, interrogatives, personalization, urgency. Be sure to set a preheader so that it acts as a “continuation” of the subject line.
Prioritize your own data over general industry theory. Smart send time (AI optimized) is especially effective for large lists.
Authentication settings for SPF, DKIM, and DMARC will be required from 2024 onwards. Immediately delete hard bounces and maintain spam reporting rate below 0.1%.
Open rates are likely to be overestimated due to Apple MPP. CTOR, which shows "what percentage of people who opened the page clicked," is a pure indicator of the quality of the text.
AI automatically optimizes the subject line, body text, and timing for each contact. Accuracy is determined by the quality of the base template and Brand Identity settings.