Postmark vs WorkOS
Reliable transactional email with fast delivery
vs. The modern identity platform for B2B SaaS
Pricing tiers
Postmark
Free
100 emails/month forever. No credit card. Side projects and testing.
Free
Basic — 10k
10,000 emails/month. Overage $1.80/1k. Unlimited emails/day.
$15/mo
Pro — 10k
10,000 emails/month. Overage $1.30/1k. Inbound email + message streams.
$17/mo
Platform — 10k
10,000 emails/month. Overage $1.20/1k. Team collab, more domains.
$18/mo
Enterprise (>1.5M)
Custom for senders exceeding 1.5M/month.
Custom
WorkOS
AuthKit Free
First 1M MAUs free. Unlimited organizations, user management, social OAuth, passwordless.
Free
AuthKit Scale
Per 1M additional MAUs.
$2500/mo
Enterprise / Annual Credits
Custom with 99.99% SLA, guided migration, dedicated support.
Custom
Free-tier quotas head-to-head
Comparing free on Postmark vs authkit-free on WorkOS.
| Metric | Postmark | WorkOS |
|---|---|---|
| mau included | — | 1000000 users/month |
| organizations | — | unlimited orgs |
| staging environments | — | free envs |
Features
Postmark · 12 features
- Activity Search — Full-text search over sent messages for 45-365 days.
- Bounce Handling — Automatic hard/soft bounce detection + suppression management.
- Broadcast Messages — Via separate Broadcast Message Stream. Bulk sends with throttling.
- DKIM + SPF — One-click verification + auto-renewal of DKIM keys.
- Inbound Email — Route inbound emails to your webhook. Parse attachments, threads.
- Message Streams — Isolate transactional from marketing for separate deliverability reputation.
- Open + Click Tracking — Configurable at template or send level.
- Raw API Access — 100+ endpoints for bounces, servers, tags, templates, stats.
- Servers — Multi-tenant isolation: each "server" has its own API token + reputation.
- Templates — Mustachio template language with variables, alias + versioning.
- Transactional Send — Reliable API for password resets, receipts, notifications. Sub-10s delivery.
- Webhook Events — Delivery, bounce, spam complaint, open, click, subscription change.
WorkOS · 13 features
- Audit Logs — Standardized audit log pipeline with streaming to SIEMs (Splunk, Datadog, Sumo L…
- AuthKit — Complete drop-in user management UI + hosted auth flows. Built on top of WorkOS.
- Directory Sync — SCIM-based user provisioning/deprovisioning from Okta, Azure AD, Google Workspac…
- FGA (WorkOS) — Fine-grained authorization based on Google Zanzibar / OpenFGA.
- Magic Auth — Passwordless email codes + links. Good alternative to password auth for B2B.
- Multi-Factor Auth — TOTP + SMS MFA enrollment and verification APIs.
- Organizations — Multi-tenant B2B primitive. Attach SSO/Directory/Audit to specific customer orgs…
- Passkeys — WebAuthn passkeys as a first-class factor.
- Radar — Fraud protection: device fingerprinting + risk scoring at signup and login.
- Single Sign-On — Plug-and-play SAML 2.0 + OIDC SSO with 30+ identity providers pre-mapped.
- User Management — REST API + webhooks for user CRUD, email verification, sessions, MFA, metadata.
- Vault — Secret storage for tokens + per-tenant credentials.
- Widgets — Embeddable admin portals (SSO setup, directory mapping) that your customers self…
Developer interfaces
| Kind | Postmark | WorkOS |
|---|---|---|
| SDK | postmark-dotnet, postmarker (Python), postmark-go, postmark (Node), postmark-php, postmark-rails | workos-go, @workos-inc/authkit-nextjs, workos-java, workos-node, workos-php, workos-python, workos-ruby |
| REST | Postmark REST API | WorkOS REST API |
| OTHER | Inbound Email, SMTP Relay, Webhooks | Webhooks |
Staxly is an independent catalog of developer platforms. Outbound links to Postmark and WorkOS are plain references to their official websites. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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