The Postmark alternative
you actually own.
Postmark keeps your transactional sending on its platform and meters it by volume. Vectis Mail gives you the same transactional API and inbound webhooks — self-hosted on your infrastructure, at a flat $0–39/month no matter how much you send, with IMAP/POP3 mailboxes included in the same product.
The cost math
Postmark prices per email past the base bucket. Vectis Mail prices per tenant. Flat cost wins as volume climbs.
| Monthly volume | Vectis Mail (Pro + ~$20/mo VPS) | Postmark |
|---|---|---|
| 100 emails | $0 (Starter, no VPS needed for tiny volume) | $0 (Free tier, never expires) |
| 10,000 emails | $39/mo flat | $15–18/mo (Basic / Pro / Platform) |
| 50,000 emails | $39/mo flat | ~$70/mo (Pro + 40K overage at $1.30/1000) |
| 100,000 emails | $39/mo flat | ~$134/mo (Pro + 90K overage) |
| 500,000 emails | $39/mo flat | ~$654/mo (Pro + 490K overage) |
| 1,000,000 emails | $39/mo flat | ~$1,200/mo (Platform + overage at $1.20/1000) |
| 5,000,000+ emails | $39/mo (may need a larger VPS at this scale) | ~$6,000/mo + DMARC/dedicated-IP add-ons |
Postmark pricing per Postmark's published pricing, retrieved 2026-05-13. Vectis Mail assumes a ~$20/mo VPS + Pro tier; Starter ($0) works for up to 3 domains and 25 mailboxes per domain. Costs at high volume may need a larger VPS; the Pro tier itself stays flat.
At a glance
Side-by-side, current as of July 2026.
| Vectis Mail | Postmark | |
|---|---|---|
| Hosting model | Self-hosted (your VPS, your IPs) | Managed SaaS (US-primary) |
| Pricing model | Flat per-tenant ($39 USD/tenant/mo Pro, unlimited installs) | Per-email after the 10K base bucket |
| Effective cost @ 100K emails/mo | $39/mo Pro + ~$20 VPS | ~$134/mo |
| Effective cost @ 1M emails/mo | $39/mo Pro + ~$20 VPS | ~$1,200/mo |
| Transactional sending API | REST + SMTP, domain-scoped keys, batch, attachments | REST + SMTP, mature SDKs |
| Inbound webhooks | Yes — HMAC-signed, retry-with-backoff | Yes — mature, well-documented |
| Mailbox hosting (IMAP/POP3) | Yes — Roundcube webmail included | No — send + inbound parse only |
| Message Streams (txn / broadcast separation) | Set up with separate domains/installs | Yes — built-in |
| Email templates | Stored + rendered locally | Hosted in Postmark, JSON-exportable |
| IP warmup required | 2–4 weeks on a fresh IP | No — pre-warmed shared pool |
| Sender vetting | You own the decision | Strict — some senders rejected at signup |
| Data sovereignty | Full — content + metadata on your infra | US-primary; ActiveCampaign-owned |
| Underlying stack control | Full Postfix/Rspamd/Dovecot access | None — black-box SaaS |
| Analytics retention | Your Postgres, indefinite | 45–365 days, tier-dependent |
| Marketing/broadcast features | Transactional + receive only | Transactional-first; broadcast is light |
| Compliance off-the-shelf | You operate the controls | SOC 2, GDPR, HIPAA-eligible |
| License | Business Source License 1.1 (auto-Apache 2.0 after 4y); commercial Pro license | Proprietary SaaS |
Why teams move to Vectis Mail
Where per-email billing and send-only hosting start to hurt.
- Your Postmark bill is above ~$50/month and the per-email model doesn't match your cost structure.
- Data sovereignty matters: you're in EU regulated industries, healthcare, government, or trying to keep email content off third-party infrastructure.
- You also need to host mailboxes (e.g.
support@yourdomain) and want one product for inbound + outbound instead of a separate mail server. - You want full control over the underlying mail stack: Postfix tuning, custom Rspamd rules, custom headers.
- You're a SaaS, agency, or reseller running mail for many client domains — one Pro subscription covers unlimited installs.
- You'd prefer to own your infrastructure roadmap rather than depend on a third party's product direction.
- You want to make your own deliverability and sender-policy decisions rather than pass a provider's sign-up vetting.
One honest scope note: Vectis Mail is built for transactional and inbound email plus hosted mailboxes — not marketing-campaign broadcasting with list management, A/B testing and broadcast analytics. If you run large marketing sends, pair Vectis Mail with a dedicated campaign tool for that lane.
How they differ
Pricing model
Postmark prices per email past a 10,000-email base bucket. Tiers are mostly differentiated by features (retention, domains, users) rather than volume — Basic, Pro, and Platform all start with the same 10K bucket. Overages run $1.20–$1.80 per thousand emails depending on tier. Add-ons (dedicated IPs from $50/mo, custom retention from $5/mo, DMARC monitoring from $14/mo per domain) compound. At 100,000 emails/month you're at roughly $134; at 1M, roughly $1,200.
Vectis Mail prices per tenant. Starter is free forever; Pro is $39 USD/tenant/month for unlimited domains, unlimited mailboxes, unlimited email volume. Add a ~$20/month VPS and your fully-loaded cost is $59/month whether you send 10,000 or 10 million emails. One Pro subscription covers unlimited Vectis Mail installs — useful for SaaS operators, agencies, and resellers running mail for many client domains.
The cost crossover lands roughly in the mid-tens of thousands of emails per month — the exact figure depends on your Postmark plan and overage rate. Past that point, every email Postmark sends costs you something while every email Vectis Mail sends costs nothing additional, so the gap widens as you grow.
API surface
Conceptually similar. Both offer a REST API with single + batch sending, template rendering, event webhooks (delivered, open, click, bounce, spam complaint), and inbound parsing.
Postmark and Vectis Mail both use an API; see the API Referencefor the full surface. Migration is mostly mechanical: replace the Postmark SDK call with an HTTP POST, re-map webhook field names (similar shape, different keys), re-create templates locally.
Message-stream separation
Postmark's Message Streams give transactional and broadcast email separate sender reputation, so a marketing-list bounce doesn't poison your password-reset deliverability. It's handled with one built-in setting.
Vectis Mail routes all outbound through one Postfix queue, so you build that separation yourself — running separate Vectis Mail installs (one for transactional, one for broadcast) or using different sending domains with separate DKIM keys. It's a configuration pattern rather than a one-click switch, and worth scoping up front if multi-stream reputation separation is core to how you send. It's a deliberate trade for owning the whole stack.
Mailbox hosting + inbound
Postmark is send + inbound-parse only. To host a mailbox likesupport@yourdomain that receives replies a human reads, you need a separate mail server or another service. Postmark's Inbound Parse handles receiving for programmatic processing but isn't a full IMAP/POP3 mailbox.
Vectis Mail handles both. The same instance hosts user mailboxes (IMAP/POP3 + the full Roundcube webmail) and runs inbound webhooks for programmatic processing. One product, one set of DNS records, one cost line.
Deliverability + IP warmup
On a managed shared pool you inherit an existing reputation from day one. Vectis Mail puts you on your own IP, which means 2–4 weeks of gradual volume ramp before a fresh IP reaches an equivalent standing.
You don't take a day-one hit when migrating: the dual-send playbook keeps your current provider delivering production mail while your Vectis Mail IP warms, so there's no reputation gap during the switch. After warmup, self-hosted deliverability with properly configured DKIM/SPF/DMARC/MTA-STS comes down to your IP reputation and DNS hygiene, not the platform you send from — and Vectis Mail ships those configured correctly by default. The IP warmup guide walks through the calendar.
Data sovereignty + parent-company risk
Postmark stores email content + metadata on US-primary infrastructure. Postmark itself was acquired by ActiveCampaign, whose strategic focus is marketing automation rather than transactional infrastructure. The product is still maintained today, but the roadmap depends on a parent company whose primary business is elsewhere. That's worth weighing if you're planning a multi-year infrastructure bet.
Vectis Mail runs on your VPS. Email content, metadata, and analytics live in your Postgres. You control where that data resides (EU VPS, sovereign cloud, on-prem, whatever fits your jurisdiction) and who has access. For organisations in regulated industries like healthcare, government, financial services, or the EU public sector, this is often the dealbreaker.
Migrating from Postmark to Vectis Mail
The migration shape is similar to a SendGrid migration. The mechanical parts are straightforward; IP warmup is the gating factor.
- Stand up Vectis Mail on a fresh VPS following the installation guide. Configure your sending domain(s) but leave DNS pointed at Postmark for now.
- Wire the API: replace Postmark SDK calls with HTTP POSTs to Vectis Mail's sending endpoints. Field mapping is mostly direct (To/From/Subject/HtmlBody → to/from/subject/html). See the API Reference.
- Re-create templates: export Postmark templates (JSON export available in the Postmark dashboard), store them in your codebase, and render them locally before sending via Vectis Mail. This is a one-off conversion.
- Re-point webhooks: update your webhook destination from Postmark's to Vectis Mail's. Event field names differ slightly but the shape (delivered, bounced, opened, clicked, complained) is the same.
- Generate new DKIM keys on Vectis Mail and publish them to DNS alongside the existing Postmark keys. Both can validate in parallel during the switchover.
- Run IP warmup: send progressively larger volumes over 2–4 weeks. Vectis Mail has built-in IP warmup tracking — see the IP warmup guide.
- Dual-send during transition: route a percentage of traffic through Vectis Mail while the rest goes through Postmark. Increase the percentage as IP reputation builds.
- Cut DNS over: update MX (if you're moving mailboxes too) and the From-domain DKIM/SPF to point at Vectis Mail. Decommission Postmark once you've verified delivery rates match.
Realistic timeline: 1 week to wire + test, 3 weeks of warmup, 1 week to decommission. Total around 5 weeks for a clean cutover. Analytics history doesn't migrate — Postmark doesn't offer bulk event-data export — so factor in any reporting continuity you need.
Frequently asked questions
Is Vectis Mail a drop-in replacement for Postmark?
On the transactional sending + inbound parse + webhook surfaces, yes. The migration is mechanical: swap the Postmark SDK call for an HTTP POST, re-map webhook field names, re-create templates, regenerate DKIM keys, update DNS. Vectis Mail also adds mailbox hosting (IMAP/POP3 + webmail) in the same product, which Postmark doesn't — handy if you've been running Postmark alongside a separate mail server. One scope note: Vectis Mail routes all outbound through one Postfix queue, so if you rely on separate transactional and marketing sender reputations you'll set that up with separate domains or installs — configuration work rather than a built-in stream feature.
How do the costs compare at scale?
Postmark's base plans start at $15–18/month for 10,000 emails, with overages at $1.20–$1.80 per thousand depending on tier. At 100,000 emails/month you're paying roughly $134/month on Pro; at 1 million you're around $1,200/month on Platform. Vectis Mail is $39/month flat regardless of volume (Pro tier), plus a ~$20 VPS to host it — about $59 all-in. The cost crossover lands roughly in the mid-tens of thousands of emails per month, depending on your Postmark plan and overage rate. Past that point, every email Postmark sends costs you something, while every email Vectis Mail sends costs nothing additional.
What about Postmark's Message Streams — does Vectis Mail have an equivalent?
Not as a single built-in switch. Message Streams gives transactional and broadcast email separate sender reputation, so a marketing-list bounce doesn't poison your password-reset deliverability. Vectis Mail routes all outbound through one Postfix queue, so you set up that separation yourself — running separate Vectis Mail installs (one for transactional, one for broadcast) or using different sending domains with separate DKIM keys. It's configuration work rather than a one-click feature, and worth scoping up front if multi-stream reputation separation is core to how you send.
What about deliverability on a self-hosted server?
On a fresh VPS IP you build reputation rather than inherit it: plan for 2–4 weeks of gradual IP warmup before a new IP reaches an equivalent standing. You don't take a day-one hit when migrating — thedual-send playbook keeps your current provider delivering production mail while your Vectis Mail IP warms, so there's no reputation gap during the switch. After warmup, self-hosted deliverability with DKIM/SPF/DMARC/MTA-STS properly configured comes down to your IP reputation and DNS hygiene, and Vectis Mail ships those configured correctly by default.
Try Vectis Mail
Self-hosted transactional sending + inbound webhooks + mailboxes. Flat price, your infrastructure.
Other Vectis Mail alternatives
Coming from a different stack? Read the comparison that matches it.
vs Mailcow →
Same self-hosted stack, declarative YAML config, REST API, atomic updates with rollback.
vs iRedMail →
Compared with the long-running OS-native open-source mail stack: REST API, declarative YAML, Rspamd by default.
vs Mail-in-a-Box →
One-command personal email sovereignty vs API-first multi-domain infrastructure. When each is the right fit.
vs SendGrid →
Same API surface, no per-email pricing. Flat $0–$39/mo covers unlimited sending volume.