FortiMail 900G
650,000 messages/hour with full ATP, 500 email domains
- Enterprise ATP
- 650,000 msg/hr
- Email routing
- 1.3 Million msg/hr
- Email domains
- 500
The FortiMail 900G handles 1.3 Million messages per hour of email routing and 650,000 messages per hour with enterprise advanced threat protection enabled, across 500 email domains and 1,500 server-mode mailboxes.
650,000 messages an hour with ATP, 500 domains and 1,500 server-mode mailboxes with expansion to 8 TB. The mailbox figure signals the real shift: this is the first model comfortable operating as a full mail server rather than a filter in front of one. If you are only filtering, compare it against the 400F on volume alone, server mode is where the extra capability lives.
How to work out whether it fits
The arithmetic a datasheet leaves out. If any of it does not match your situation, that is worth a call rather than a guess.
The step to consider here is not throughput, it is server mode. Fifteen hundred mailboxes and 8 TB of storage means FortiMail can be the mail system rather than a filter in front of one, and that is a materially different project, migration, retention, backup and user support all change. If you are only filtering, price the 400F against this on volume alone; the mailbox capacity is only worth paying for if you intend to use it.
What to order alongside the FortiMail 900G
The published threat protection figure for this model is measured with IPS, application control and malware protection all running. Those arrive as a FortiGuard subscription, so the bundle you choose decides whether the hardware can reach the number you sized it on. Every bundle already includes FortiCare Premium 24x7 support.
| Bundle | What it adds | 1 yearlist price | 3 yearslist price | 5 yearslist price |
|---|---|---|---|---|
| Enterprise ProtectionENT | The broadest bundle. Everything in UTP, plus the services that cover data, SaaS posture and attack-surface visibility, plus inline zero-day malware prevention. | on quote | on quote | on quote |
| Unified Threat ProtectionUTP | The traditional mid-tier: perimeter defence covering network, file, web and email threats. Everything most sites actually switch on. | on quote | on quote | on quote |
| Advanced Threat ProtectionATP | The narrow bundle: IPS and the full malware stack including cloud sandboxing, without the web and email filtering layers. | on quote | on quote | on quote |
These are Fortinet list prices. You will not pay them.
Every quote we write is discounted from list, and how far below depends on quantity, term and whether we register the deal with Fortinet. Longer terms also price better per year, which is why three and five year bundles are usually the better buy on a device you intend to keep through a refresh cycle. Part numbers follow Fortinet’s standard bundled convention; not every model carries every combination, so we confirm the exact orderable SKU before anything is placed.
FortiMail 900G is number 3 of 5 in this family
Ranked on performance enterprise atp, the figure that separates these models. All values are Fortinet’s own and cited on each product page.
FortiMail 400F
150K msg/hr
333% less than the FortiMail 900G. Worth it only if your measured requirement genuinely fits inside it.
FortiMail 900G
650K msg/hr
5 models in this family span 30K msg/hr to 2.1M msg/hr.
FortiMail 2000F
800K msg/hr
23% more headroom. Worth costing if you expect growth inside the refresh cycle, replacing early is dearer than buying up once.
Highlights
- 650,000 messages/hour with ATP enabled
- 500 email domains, 1,500 server-mode mailboxes
- Gateway, transparent and full server deployment modes
- Outbound DLP and encryption for regulated data
Typical deployments
- Organisations running FortiMail as the mail system itself
- Large multi-domain estates with heavy inbound volume
- Environments consolidating regional mail gateways
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) | 1.3 Million |
|---|---|
| Performance enterprise ATP (msg/hr) | 650,000 |
| Email domains | 500 |
| Server mode mailboxes | 1,500 |
| Storage capacity | 2x 2 TB (8 TB max) |
Sources
- Fortinet Product Matrix (July 2026), retrieved 2026-09-01
- Fortinet Partner Portal price list, 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.