HTTPS enforced with HSTS in Email marketing
We measure this ourselves on their own site. It is the cheapest security control there is.
19 of 35 companies we measured here publish it, that is 54%. Last checked 2026-10-15.
54% here against 62% across every category we measure. Email marketing sits below the overall share for this criterion.
This page counts companies, not product entries: a company with two products in this category is one company here and two rows below.
Back to HTTPS enforced with HSTS across all categories, or to Email marketing.
- Found19
- Not found at checked addresses16
- Not measured2
37 companies in total. Unmeasured companies are excluded from the published share.
Published
HTTP redirects to HTTPS and the HSTS header is set.
| Vendor | What we found |
|---|---|
| ActiveCampaign | https://activecampaign.com/Checked |
| Brevo | https://brevo.com/Checked |
| Brick Street CONNECT | https://brickstreetsoftware.com/Checked |
| Buttondown | https://buttondown.com/Checked |
| Cloudy | https://cloudy.email/Checked |
| Customer.io | https://customer.io/Checked |
| Elastic Email | https://elasticemail.com/Checked |
| Emailable | https://emailable.com/Checked |
| EmailOctopus | https://emailoctopus.com/Checked |
| Klaviyo | https://klaviyo.com/Checked |
| MailBluster | https://mailbluster.com/Checked |
| Mailgun | https://mailgun.com/Checked |
| Mailmodo | https://mailmodo.com/Checked |
| MailPoet | https://mailpoet.com/Checked |
| Omnisend | https://omnisend.com/Checked |
| Postmark | https://postmarkapp.com/Checked |
| Sender | https://sender.net/Checked |
| Substack | https://substack.com/Checked |
| Warmbox | https://warmbox.ai/Checked |
No enforced HTTPS with HSTS found.
We reached at least one address for each of these vendors and none of them carried it. That is what we found at the addresses we checked, on the date we checked them, and not a statement about what the vendor has.
| Vendor | What we found |
|---|---|
| AWeber | 2 addresses checkedChecked |
| Benchmark Email | 2 addresses checkedChecked |
| Campaign Monitor | 2 addresses checkedChecked |
| CleverReach | 2 addresses checkedChecked |
| Constant Contact | 2 addresses checkedChecked |
| Emailchef | 2 addresses checkedChecked |
| Flodesk | 2 addresses checkedChecked |
| inwise | 2 addresses checkedChecked |
| Inxmail | 2 addresses checkedChecked |
| Kit | 2 addresses checkedChecked |
| Mailchimp | 2 addresses checkedChecked |
| Mailcoach | 2 addresses checkedChecked |
| MailerLite | 2 addresses checkedChecked |
| Pinpointe | 2 addresses checkedChecked |
| Rapidmail | 2 addresses checkedChecked |
| SendFox | 2 addresses checkedChecked |
Not measured
We could not look at these, or their robots.txt asks us not to. That says something about our measurement, not about them, and they are left out of the percentage above.
Other criteria in Email marketing
- Data processing agreement
- Subprocessor list
- Data location stated
- Status page with history
- Public pricing
- Certifications named
- Uptime SLA with a figure
- No third-party tracking before consent
- security.txt (RFC 9116)
- Notice before subprocessors change
- Named privacy contact
HTTPS enforced with HSTS in related categories
Found something we missed? Tell us. A correction moves that vendor into our next nightly run. That run reads the same fixed addresses we check for every vendor, not the address you send.