Alternatives to Substack
Other Email marketing vendors we measure, sorted by how much they publish that Substack does not. This is a comparison of disclosure, not of features or fitness.
12 shown of 20 that differ from Substack on at least one criterion we measured for both. Public transparency score, not a product or security rating.
Substack has 7 gaps in what we could measure: Data processing agreement, Subprocessor list, Public pricing, Certifications named, Uptime SLA with a figure, security.txt (RFC 9116), Notice before subprocessors change. The column “publishes and Substack does not” is the one that closes them.
| Vendor | Score | Publishes, and Substack does not | Substack publishes, and they do not | |
|---|---|---|---|---|
| Mailgunmailgun.com | 83/100 | 5 Data processing agreement, Public pricing, Certifications named, +2 | nothing | Compare |
| ActiveCampaignactivecampaign.com | 78/100 | 5 Data processing agreement, Subprocessor list, Certifications named, +2 | nothing | Compare |
| Customer.iocustomer.io | 80/100 | 4 Data processing agreement, Subprocessor list, Public pricing, +1 | nothing | Compare |
| Klaviyoklaviyo.com | 65/100 | 4 Data processing agreement, Subprocessor list, Public pricing, +1 | 1 Data location stated | Compare |
| Mailchimpmailchimp.com | 57/100 | 4 Data processing agreement, Subprocessor list, Public pricing, +1 | 2 Status page with history, HTTPS enforced with HSTS | Compare |
| Omnisendomnisend.com | 57/100 | 4 Data processing agreement, Public pricing, security.txt (RFC 9116), +1 | 1 Data location stated | Compare |
| CleverReachcleverreach.com | 48/100 | 2 Public pricing, security.txt (RFC 9116) | 1 HTTPS enforced with HSTS | Compare |
| EmailOctopusemailoctopus.com | 43/100 | 2 Data processing agreement, Public pricing | 2 Status page with history, Named privacy contact | Compare |
| Postmarkpostmarkapp.com | 35/100 | 2 Data processing agreement, Public pricing | 2 Data location stated, Status page with history | Compare |
| Brevobrevo.com | 23/100 | 2 Public pricing, Certifications named | 3 Data location stated, Status page with history, Named privacy contact | Compare |
| Mailmodomailmodo.com | 22/100 | 2 Public pricing, Certifications named | 3 Data location stated, Status page with history, Named privacy contact | Compare |
| Campaign Monitorcampaignmonitor.com | 17/100 | 2 Public pricing, security.txt (RFC 9116) | 2 Data location stated, HTTPS enforced with HSTS | Compare |
Only criteria we could measure for both are counted. Where we could measure one and not the other, the row is silent: that would be a statement about our measurement, not about either vendor. Every single result with its source is on the two profiles.