Stalwart proved how clean a modern mail server can be. SharpMailserver goes decisive steps further: a built-in Light/Dark Webmail PWA with 15 color themes, OpenTelemetry & structured logs with live UI, native GoBD WORM, OCR & ZUGFeRD invoice compliance, and 25% to 28% lower per-mailbox licensing.
Capability / Metric
SharpMailserver
Stalwart Enterprise
hMailServer
Postfix + Dovecot + Rspamd
Microsoft 365 / Exchange
License price (25 to 499 mailboxes)
€1.50 per mailbox per year-25%
€2 per mailbox per year
€0 (Discontinued / Legacy)
€0 (high DevOps cost)
approx. €140.40 per user per year
Digital Sovereignty & Deployment
100% On-Prem / Private Cloud (DE) / Container
On-Prem / Container
Windows On-Prem only
Linux / multi-container
US Cloud (CLOUD Act) / heavy VM
Docker Compose & Native Windows Service
Docker Compose + Windows Service + Linux + macOS + K8s
Autoconfig + Autodiscover + PKCS#7 .mobileconfig QR
Autoconfig / Autodiscover (no signed QR)
(Manual XML)
Autodiscover only
JMAP (RFC 8620/8621) + IMAP4rev2
Both natively integrated
(Legacy IMAP4rev1 only)
(No JMAP)
(Proprietary Graph/MAPI)
Compared to Stalwart Enterprise
25 % bis 28 % günstiger auf jeder Stufe: €1.50 vs. €2 per mailbox per year (Tier 1) down to €0.65 vs. €0.89 per mailbox per year (Tier 6) with identical unlimited domains, tenants & servers.
Webmail PWA direkt eingebaut: No separate Roundcube or external JMAP frontend deployment needed: SharpMail Web PWA ships right at /mail/.
GoBD, OCR & ZUGFeRD aus Deutschland: Purpose-built for European tax & e-invoicing mandates (EN 16931 ZUGFeRD extraction + scan OCR + non-mutating Auditor cockpit).
Autoconfig, Autodiscover + signiertes Apple-QR: Beyond full Mozilla Autoconfig and Microsoft Autodiscover (XML/JSON), one camera scan installs a PKCS#7/CMS-signed Apple .mobileconfig profile (Verified ✓) with an isolated per-device App Password.
Compared to hMailServer (Windows)
Sowohl nativer Windows-Dienst als auch Docker Compose: hMailServer is discontinued and lacks JMAP, Passkeys, Ed25519 DKIM, ARC, DANE, OpenTelemetry, and built-in ACME TLS. SharpMailserver runs either as a native Windows Service or via Docker Compose.
1-Klick Direktimport: SharpMailserver natively imports your existing hMailServer Data\*.eml folders, domains, aliases, and distribution lists.
Compared to Postfix + Dovecot + Rspamd
Ein Dienst (~58 MB Idle-RAM) statt 9 Daemons: Eliminate fragile milter/socket chains and multi-gigabyte RAM overhead across Postfix, Dovecot, Rspamd, OpenDKIM, OpenDMARC, Redis, and Certbot scripts.
Zentrale Logs & OpenTelemetry: Manage queues, TraceId-correlated logs, DKIM rotation, CIDR bans, and mailboxes in one compact real-time dashboard.
Compared to Microsoft 365 / Exchange
Bis zu 98 % Kostenersparnis: For 500 users, SharpMailserver licensing is roughly €750 per year compared to over €70,000 per year for Microsoft 365 Business Standard.
100% On-Prem / Private Cloud (DE) / Container: Zero US CLOUD Act exposure: every byte and private key stays 100% On-Prem, in your German/EU Private Cloud, or in your own containers.
