The main reason people pay expensive ESPs is deliverability, which is practically impossible when self-hosting when it comes to marketing, non-transactional emails, and in any case much more expensive than any ESP subscription.
How does Fertit position itself in relation to that?
Fertit actually leverages the best of both worlds through our SMTP integration approach:
Use Established ESPs for Delivery: Fertit connects to your existing SMTP provider (SendGrid, Mailgun, Amazon SES, etc.) - so you still get their deliverability infrastructure and IP reputation.
Save on Interface & Features: Instead of paying $50-300/month for ConvertKit or Mailchimp's full platform, you pay $5-10/month for Fertit's management layer while using a cheaper transactional email service for actual delivery.
Cost Comparison:
Traditional ESP: $79/month for 5,000 subscribers
Fertit approach: $9.99/month (Pro plan) + $15/month (SendGrid) = ~$25/month total
Deliverability is not a purely technical SMTP-level issue. It also involves domain/IP reputation, email content quality, bounce rate management, spam complaints etc etc etc. Also I'm pretty sure there is a buuuunch of compliance stuff you can't just punt to SES no? How much are you handling on your side and how much can SES do?
Fertit provides essential newsletter infrastructure (preferences, unsubscribes, basic compliance) for a low cost (1.99-9.99$/month) vs $79 for full-service ESPs, but users handle advanced deliverability optimization themselves.
It's positioned between "raw SMTP" and "full-service ESP" - covers the regulatory basics but not the sophisticated deliverability management that determines inbox placement rates.
Don’t most of these services explicitly disallow using them for newsletter type of use? If you send a bunch of the same types of emails to bursts of thousands of users at once, those companies have algorithms that will eventually pick it up (especially if there are lots of images/content embedded).
Am I misunderstanding the limitations of which services are available to use for “bring your own SMTP”?
Good point! You're absolutely right that many basic SMTP providers (Gmail, Outlook, etc.) restrict bulk newsletter sending to large number of emails.
Fertit is designed to work with newsletter-appropriate SMTP services like SendGrid, Mailgun, Amazon SES, Postmark, and Mailjet - providers that explicitly
support bulk email sending. These typically cost $10-50/month depending on volume, which is still much cheaper than the $79+ full-service ESPs charge.
The value prop is: instead of paying ConvertKit $79/month for 1000 subscribers, you pay SendGrid ~$15/month for SMTP + Fertit $9.99/month = ~$25/month total, while still getting proper unsubscribe handling, preference management, and basic compliance features.
You're right that it requires users to handle the SMTP setup themselves - it's positioned for people who want more control and cost savings but don't need the full white-glove deliverability management of premium ESPs.
Thanks for pointing this out - I should make the SMTP requirements clearer in the marketing!
If you look at Postmarks website, they explicitly disallow the service you are promoting. Marketing emails are not allowed to be sent through Postmark.
I generally like your idea, but as someone in growth, I hope you provide the users with a lot of instruction and warning on compliance, CASL are particularly eager to enforce.
Fertit handles the core compliance infrastructure (double opt-in, one-click unsubscribe, preference management, suppression lists) but you're right that users need clear guidance on the legal requirements.
You can still pair with Sendgrid or SES, etc. It doesn't have to be THAT expensive. I think the hardest part is figuring out how you need to enter some of the DNS settings depending on where your DNS is provided and the UI/UX.
Aside: I really wish Google hadn't sold off domains.
How does Fertit position itself in relation to that?