FortiMail 400F
150,000 messages/hour with full ATP, 70 email domains
- Enterprise ATP
- 150,000 msg/hr
- Email routing
- 250,000 msg/hr
- Email domains
- 70
The FortiMail 400F handles 250,000 messages per hour of email routing and 150,000 messages per hour with enterprise advanced threat protection enabled, across 70 email domains and 400 server-mode mailboxes.
Five times the 200F on both throughput figures and 70 domains against 20 — the domain count is often the binding constraint rather than the message rate, particularly for organisations that have grown by acquisition and carry a long tail of legacy mail domains. Count those before sizing on volume.
Highlights
- 150,000 messages/hour with ATP enabled
- 70 email domains, 400 server-mode mailboxes
- Gateway, transparent and full server deployment modes
- Outbound DLP and encryption for regulated data
Typical deployments
- Multi-domain organisations after acquisitions
- Mid-size estates with meaningful inbound volume
- Deployments needing transparent-mode inline filtering
What this includes
Fortinet publishes no throughput table for this product — it is licensed per user, endpoint, workload or account. What follows is capability and sizing, not benchmarks.
Capacity
Measured at a 100 KB average message size with no queuing.
| Email routing (msg/hr) | 250,000 |
|---|---|
| Performance enterprise ATP (msg/hr) | 150,000 |
| Email domains | 70 |
| Server mode mailboxes | 400 |
| Storage capacity | 2x 1 TB |
Sources
- Fortinet Product Matrix (July 2026) — retrieved 2026-09-01
Reproduced from Fortinet published documentation and subject to change without notice. Where a figure is load-bearing for your design, ask us to confirm it in writing before you order — we will.