Dedicated email security for Office 365
Microsoft Defender for Office 365 is a fine baseline, but targeted phishing, business email compromise, and zero-day payloads still get through. MailRoute becomes the dedicated filter in front of your tenant — more accurate, with far fewer false positives and one quarantine to manage. Most customers route mail through MailRoute and set Defender’s spam filtering to a pass-through; keep it as a second layer if you’d rather.
Defender is a jack of all trades
Exchange Online Protection and Defender for Office 365 handle a broad surface area: anti-malware, Safe Links, Safe Attachments, anti-phishing policies. But Microsoft is building a platform, not a dedicated email security product.
Phishing spoofing internal domains, BEC with clean URLs, social engineering that looks like legitimate mail. These get past Defender every day. It wasn’t built to be a dedicated email security product.
91%
of cyberattacks start with a phishing email
$4.9M
average cost of a data breach in 2024
MailRoute sits in front as a dedicated gateway
Every inbound message hits MailRoute’s filtering before reaching Exchange Online: threat intelligence, NRD blocking, AI analysis, and virus scanning. Clean mail delivers. Everything else is quarantined. Authorize once with Microsoft Graph and your user list, connectors, and mail flow are configured and validated for you.
Configured for you. Kept correct automatically.
The inbound connector, outbound connector, Enhanced Filtering, ARC sealing, and direct-send lockdown all have to be exactly right, and they drift. MailRoute continuously validates every part of your Exchange Online mail flow and fixes misconfigurations with one click. No PowerShell archaeology when something breaks.
Prefer to run it yourself? Every check exposes the exact PowerShell command, and our step-by-step setup guide walks through the manual path.
Key features for Office 365
Automatic User Sync
MailRoute syncs your Office 365 user list automatically via the Microsoft Graph API. New mailboxes are protected the moment they're created. Deprovisioned accounts are removed. No manual list management.
One Quarantine, Your Call
Point your MX at MailRoute and it becomes the authoritative filter for your tenant — one engine making the decision, one quarantine to review. Most customers set Defender's anti-spam policy to a pass-through (via Enhanced Filtering) so there's a single place to look. Prefer belt-and-suspenders? Keep Defender running behind MailRoute as a second layer. It's the admin's choice.
Guided Onboarding
Authorize MailRoute to sync your user list via Microsoft Graph API with a single OAuth step, then we configure and validate your connectors. MailRoute guides you through the MX record change too. Most tenants are fully protected in under 10 minutes.
IP-Restricted Delivery (via Transport Rules)
Configure Exchange Online transport rules to accept mail only from MailRoute's IP ranges. All inbound mail passes through our filters first. There's no way to bypass the gateway.
Full Visibility
Real-time mail logs show you every message (delivered, quarantined, or rejected) with full header detail. Track any message from MailRoute's filters through to Exchange Online delivery.
GCC & GCC High Compatible
MailRoute works with Government Community Cloud environments, including GCC High. If your organization requires FedRAMP-compliant email security in front of Office 365, we support it.
Office 365 plans start at $2/user/month
Every plan includes full inbound filtering, Office 365 integration, quarantine management, and a free 30-day trial. No credit card required.
Basics — $2/user/mo
Inbound and outbound filtering, content filtering, DKIM signing, quarantine notifications, real-time mail logs. MX-level integration with Office 365. Point your records to MailRoute and you’re protected.
Enterprise — $3/user/mo
Everything in Basics, plus automatic user sync via Microsoft Graph API, SSO, LDAP/AD sync, phone support, email continuity, and white-glove migration assistance.
Enterprise U.S. — $4/user/mo
Everything in Enterprise, plus US-only datacenters, US-citizen account access, International Traffic in Arms Regulations (ITAR) compliance, and HIPAA readiness with Business Associate Agreement (BAA).
Start free trial with your O365 tenant
Full-featured 30-day trial. Guided onboarding. No credit card required.