Secure Message

Secure Message is a self-hosted gateway for organizations that want to filter email and control protected-message delivery without moving their mailboxes. It is strongest for IT and compliance teams able to run a Debian appliance; smaller teams seeking a hosted, low-commitment encryption tool should look elsewhere.

Overview

Secure Message filters inbound mail before it reaches Microsoft 365 or another existing mail server. MX routing directs mail through the gateway, while an outbound smart-host relay handles outgoing mail, so deployment does not require mailbox migration. The trade-off is operational: the single-node appliance runs on Debian 13, and the maker recommends starting with 2 vCPU and 4 GB of RAM.

Stored messages, attachments and quarantine are encrypted using Fernet with AES-128-CBC and HMAC-SHA256. The key stays on the customer host, giving the organization custody of it while making host security and administration its responsibility.

Key features

The Community plan includes Postfix content filtering, spam scoring, DNSBL, SPF, DKIM and DMARC checks, quarantine and mail logs. It also includes TOTP administrator MFA, role-based access and audit logs exportable to CSV. That is a substantial inbound-control foundation, but its one-domain, one-administrator cap makes it better suited to a small installation than a multi-team rollout.

Professional adds a web portal for protected messages. Recipients open messages with a one-time code, without an account or app, which reduces friction for people outside the organization. Outbound rules can encrypt, redirect or block sensitive mail, or hold it for portal delivery. SMTP callout, LDAP or directory lookups can reject mail addressed to nonexistent users.

Enterprise adds AI Autopilot tuning, eDiscovery and archive search, DLP and disclaimers. Autopilot and the classifier are off by default, so teams should not assume automated tuning is active on installation. Community support comes with the free tier, Professional includes business-hours support, and Enterprise adds priority support and an SLA. Users can request a scoped trial with engineering.

Pricing

Community has no published price and is capped at 1 domain and 1 administrator. It is the practical starting point for evaluating inbound filtering, but it does not include Professional's protected-message portal and outbound rules.

Professional costs $690 a year, billed annually, for 10 domains and up to 10 users. It fits organizations that need recipient-portal delivery and outbound policy controls within those limits, with business-hours support. The annual billing is a poor fit for buyers who require a paid monthly option.

Enterprise costs $1,490 a year, billed annually, and supports unlimited users and domains. Its archive search, eDiscovery, DLP, disclaimers, priority support and SLA target organizations with broader compliance and operational needs. The price is a substantial step up from Professional, so smaller teams should weigh whether they need those additions. Both paid plans renew on a yearly basis.

Platforms

Secure Message is available for Linux, as a self-hosted deployment, and through the web portal. Its Debian 13 appliance requirement and recommended starting resources make it a better match for teams with infrastructure capacity than users looking for a simple desktop or mobile app.

Who it's for

The product is aimed at healthcare, finance and legal teams, managed service providers, internal IT groups and compliance-driven organizations. It is particularly relevant where administrators want to place filtering in front of an existing mail system and retain the encryption key on their own host. It is less suitable for individuals or small groups that want a hosted service without appliance administration or annual paid plans.

Pros and cons

• Pros: MX routing and smart-host relay add controls without requiring mailbox migration.
• Pros: The portal and one-time-code access let recipients receive protected messages without an account or app.
• Pros: The customer-hosted key, administrator MFA, role controls and exportable audit logs support organizations that want direct control over security operations.
• Cons: Running a Debian appliance requires infrastructure and ongoing administration.
• Cons: Community is limited to one domain and administrator, while the paid plans are billed annually.
• Cons: Autopilot and the classifier are off by default, so Enterprise buyers should account for configuration rather than assume automatic tuning.

Alternatives

For a different approach to protected email and file delivery, Lockbin has a free plan for one user with a 25 MB attachment limit and six months of inbox storage. SecureMyEmail may suit people who want a free option for one email address across mobile and desktop platforms. Send It Secure is worth considering for web, API, extension or mobile access; its free Guest plan includes 30-day retention, 25 MB files and 10 lifetime message sends to non-paid users.

gpg4o is a Windows-only option for users seeking OpenPGP encryption in Microsoft Outlook. c.Email is a free extension-based choice that supports existing email addresses and unlimited addresses. FlowCrypt may fit extension users with fewer than 100 users and a 5 MB attachment threshold on its free plan. Mimecast Secure Messaging is another paid secure-messaging option, while DataMotion Secure Email Exchange offers an enterprise email-exchange option with pricing handled through sales. For broader comparisons, browse Email Encryption Software or File encryption tools.

Verdict

Secure Message is a strong fit for organizations with the capacity to operate a self-hosted gateway and a need for inbound filtering, controlled recipient delivery and outbound policy enforcement. The customer-held key and the option to add archive search and DLP broaden its appeal for compliance-focused teams. Look elsewhere if you need a hosted, low-maintenance tool or a paid plan that does not require an annual commitment.