I need an alternative to MailerSend because of deliverability issues

If you’re having deliverability issues with MailerSend, the best alternative depends on what you’re sending:

• Transactional email: Postmark, SendGrid, Mailgun, Amazon SES
• Marketing email: Brevo, Klaviyo, Mailchimp, Customer.io
• Mixed use: SendGrid, Mailgun, SparkPost, Amazon SES

My top picks for deliverability

1. Postmark

   • Often considered one of the best for transactional email deliverability
   • Strong reputation for fast inboxing and clear logs
   • Great if you send password resets, receipts, notifications, etc.

2. Amazon SES

   • Very strong deliverability potential
   • Very low cost
   • More technical to set up and manage
   • Best if you want control and can handle configuration

3. Mailgun

   • Good developer tooling and APIs
   • Solid for transactional and some marketing use cases
   • Reputation management features are useful

4. SendGrid

   • Popular and feature-rich
   • Good all-around option
   • Deliverability can vary depending on account setup and sending patterns

If deliverability is the main concern

I’d usually suggest:

• Postmark if you send mostly transactional emails
• Amazon SES if you want the best cost/control balance
• Mailgun if you want flexibility and good API support

Common reasons deliverability is poor

Even switching providers won’t fully help if these are off:

• SPF, DKIM, and DMARC not configured correctly
• Sending from a new or low-reputation domain
• Shared IP reputation issues
• Poor list hygiene / too many bounces or complaints
• Spammy content or inconsistent sending volume

If you want, I can recommend the best alternative based on your use case:

• transactional vs marketing
• email volume
• whether you need SMTP, API, or both
• your budget