Choose AWS SES if
- Cost per send matters more than developer experience (high-volume outbound).
- You already live in the AWS ecosystem and want one bill.
- Your workload is human-to-human transactional, no agentic behavior.
Choose Loomal if
- You don't want to assemble inbound from S3 + Lambda + DynamoDB yourself.
- Your agent reads mail, reasons about it, and replies in-thread.
- Credentials, TOTP, and audit log should live with the mailbox.
- Per-agent isolation and cascading revocation are requirements, not nice-to-haves.
Feature-by-feature
| Feature | Loomal | AWS SES | Edge |
|---|---|---|---|
| Price per message (high volume) | Higher | Extremely low | |
| Inbound routing | Mailbox per identity, webhook ready | S3 + SNS + Lambda pipeline | |
| Thread stitching | Automatic | DIY | |
| LLM-ready body | extractedText out of box | Raw MIME | |
| Per-agent identity | Native | IAM roles (heavy) | |
| Vault | Built in | Secrets Manager (separate service) | |
| TOTP | Built in | None | |
| Operational burden | One API | SES + S3 + SNS + Lambda + Secrets Manager | |
| AWS integration | Webhooks to anywhere | Native CloudWatch, SNS, S3 | |
| MCP server | First-party | None |
The hidden cost of AWS SES
SES's per-message price is the number everyone quotes. What doesn't show up in that number is the integration engineering: setting up receipt rules that write to S3, Lambda functions to parse and classify, SNS topics for event routing, DynamoDB for thread state, Secrets Manager for credentials, CloudWatch for audit.
For a team that lives in AWS and has the infrastructure already, this is fine. For an agent team that just wants an API that does email and credentials correctly, Loomal collapses six services into one and takes the plumbing work off the table.
When SES is genuinely the right call
If you're sending hundreds of thousands of transactional messages per day to humans, the economics favor SES hard. No SaaS email provider can match AWS on cost per send at that scale. Loomal is not trying to.
If your workload is agent-driven and below that threshold, the calculus flips. An agent sending a few hundred emails per day but needing vault, TOTP, and a real inbox is exactly the shape Loomal was designed for — you pay a bit more per message and save ten times that in engineering hours.
FAQ
Can I use SES for outbound and Loomal for inbound?
You can, but it's usually not worth the complexity. Loomal's outbound is priced reasonably and keeping the whole mailbox under one identity simplifies threading and audit.
Does Loomal run on AWS?
Our infrastructure is multi-cloud. Customers requiring specific data residency can discuss options on enterprise plans.
Is SES's deliverability better?
Deliverability depends on sender reputation, DKIM/SPF/DMARC alignment, and content — all of which Loomal handles correctly. For typical agent volumes they're comparable.
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Last updated: 2026-04-15