whats-best.ai
Search Sign in

Transactional Email

Postmark

Rest of world Report an error

Panel rating · 6 judges · How to read the stars

Category median

Sovereignty: not determined

0–5 in half steps. 5 means the rubric's top anchor is met on the evidence.

by AC PM, LLC · postmarkapp.com

Compare with Lettermint → Compare with Mailgun → Report an error on this page Is this your product? →

Link to this page

Postmark: AI-assisted analysis on whats-best.ai Postmark: AI-assisted analysis on whats-best.ai (dark)

Add ?theme=dark to the image address for dark backgrounds. The badge shows the category and the month of the latest evaluation, and EU-Made where that is the product’s provenance. It never shows a score.

Postmark at a glance

Vendor
AC PM, LLC
Headquarters
Not stated on the vendor’s pages as of 1 Nov 2026
Data hosting
Not stated on the vendor’s pages as of 1 Nov 2026
Free plan
Yes, per the vendor’s own page source, captured 1 Nov 2026
Panel verdict
The AI panel rates Postmark 3/5, the mean of 6 judges. Postmark, the transactional email service of AC PM, LLC, an ActiveCampaign company, earns its best marks on the sending API and pricing transparency, both a flat 7, and on deliverability at 7 to 8, resting on manual vetting of every new sender, free custom Return-Path and DKIM, and separate infrastructure for transactional and broadcast traffic including IP ranges. how scores are made
As of
Vendor pages captured 1 Nov 2026; evaluated by the panel 2 Nov 2026. all sources

Postmark alternatives, European ones first →

Read this page as one judge. Each weighs the same scores by what they care about.

The Data Protection Officer

Weighted verdict

In-house data protection officer at a health software company whose appointment reminders and lab-result notices carry patients' names. Treats the sending service as a processor like any other. Reads the DPA, the subprocessor list and the retention section first: whether message bodies are stored and for how long, whether open tracking can be turned off, which entity signs, and whether the EU region covers the logs as well as the mail.

Same scores as the panel view — this lens weights them the way this judge cares.

Scored by The Data Protection Officer

Panel median The Data Protection Officer This judge’s scores over the panel median. Each label opens its reasoning below.
Scores per criterion, in stars out of 5
Criterion Panel median The Data Protection Officer
Sending API, SMTP & developer experience 3.5 of 5 3.5 of 5
Deliverability & sender reputation 4 of 5 4 of 5
Message logs, events & webhooks 3.5 of 5 3 of 5
Message data, retention & security 3 of 5 3 of 5
Reliability, accounts & support 3 of 5 3 of 5
European sovereignty 2 of 5 2 of 5
Pricing transparency 3.5 of 5 3.5 of 5

Sending API, SMTP & developer experience

How this is scored

How an application sends mail: a REST API and an SMTP relay with their limits stated, official SDKs and drivers for named languages and frameworks (PHP and Laravel, Node, Python, Ruby and Rails, Java, Go, .NET), stored templates with variables and versions, batch sending, attachments, idempotency keys, scheduled sending, a test or sandbox mode that does not deliver, inbound email parsed into a webhook, and the quality of the API reference and guides.

0 — Not a sending service; an application cannot send email through it by API or SMTP.

3 — An API or SMTP credentials to send a message; SDKs, templates, limits and a test mode are basic or not described.

5 — A documented REST API and SMTP relay, official SDKs for several named languages, stored templates with variables, attachments and batch sending, rate limits stated, a sandbox or test mode, and quick-start guides for named frameworks.

8 — An API reference with every endpoint and error code, idempotency keys, scheduled sending, template versions and a template language documented, inbound email parsed to a webhook, an OpenAPI specification or official CLI, framework drivers maintained by the vendor, and a migration guide from named competitors.

10 — An API a team builds its product on: versioning and deprecation policy published, backward compatibility stated, full parity between API and SMTP features, local or staging test tooling that mirrors production, and every limit, timeout and retry behaviour documented.

Report an error

The Data Protection Officer

A fully documented REST API with endpoints and error codes, an SMTP relay on token authentication, vendor-maintained official libraries for eight named languages plus community libraries, batch sending capped at 500 messages and 50 MB, a test token and sandbox mode, inbound email parsed to a webhook, an official CLI, and migration guides from six named competitors. We found no public information on idempotency keys, scheduled sending, template versioning or an OpenAPI specification, which is what keeps it short of the top level. 1 3 6 13 14 22

Report an error

Deliverability & sender reputation

How this is scored

What the vendor does so the mail reaches the inbox: guided SPF, DKIM and DMARC set-up with a custom return path and tracking domain, shared IP pools and how senders on them are vetted and policed, dedicated IPs with automatic warm-up, transactional and bulk mail kept on separate streams or IP pools, bounces, complaints and unsubscribes turned into suppressions automatically, feedback loops with mailbox providers, blocklist and DMARC monitoring, compliance with the Gmail and Yahoo bulk-sender rules, and published delivery times or inbox placement with their method.

0 — No sender authentication and no bounce handling; mail goes out from shared addresses with no reputation management at all.

3 — SPF and DKIM can be set up and bounces are recorded; IP policy, stream separation and suppressions are basic or not described.

5 — Guided SPF, DKIM and DMARC set-up with a custom return path, shared IPs with a stated sender vetting policy, dedicated IPs available, automatic suppression of hard bounces and complaints, transactional and marketing mail separated by stream or IP pool, and deliverability guidance in the documentation.

8 — Dedicated IPs with automatic warm-up and pool management, a stated acceptable-use and vetting process for shared pools, feedback loops and blocklist monitoring, DMARC reports, BIMI or custom tracking domains, compliance with the Gmail and Yahoo sender requirements stated, delivery times published, and access to deliverability experts.

10 — Deliverability that can be verified: delivery time and bounce rates per mailbox provider published continuously with their method, inbox placement testing included, pool reputation shown to the customer, and a documented escalation path with mailbox providers.

Report an error

The Data Protection Officer

SPF, DKIM and DMARC set-up with a free custom return path, every new sender manually vetted before sending, transactional and broadcast traffic kept on completely separate infrastructures including IP ranges, dedicated IPs from 300,000 messages a month with managed warm-up and overflow to the shared pool, feedback loops and blacklist monitoring handled by the vendor, automatic suppression, and delivery times published per mailbox provider on a public Time to Inbox page. We found no public information on a stated compliance position for the Gmail and Yahoo bulk-sender rules, or on BIMI or custom tracking domains. 1 4 5 7 15

Report an error

Message logs, events & webhooks

How this is scored

What the team can see about each message once the application has handed it over: a message log searchable by recipient, subject, tag or message ID, the full event history (processed, delivered, deferred, bounced with the remote server's answer, opened, clicked, complained), how long logs and message content are kept, event webhooks with retries and a signature, an events API, dashboards and statistics per stream, tag or domain, alerts on bounce or complaint spikes, and access for a support team without developer rights.

0 — Nothing can be seen after sending; no logs, no events and no webhooks.

3 — Totals of sent and bounced messages; per-message logs, webhooks and retention are basic or not described.

5 — A searchable message log with per-message event history and the bounce reason, log retention stated, event webhooks for delivery, bounce, open, click and complaint, statistics per tag or domain, and an API to fetch events.

8 — Webhooks signed and retried with their schedule documented, the raw SMTP response and the rendered message viewable per send, log retention configurable or extended by plan, alerts on bounce, complaint or delivery-time thresholds, export or streaming of events to a named log or data tool, and read-only roles for support staff.

10 — Full traceability: every message traceable from API call to the receiving server's final answer, events streamed in real time with ordering and delivery guarantees stated, long retention with search across the whole history, and observability features documented with their limits.

Report an error

The Data Protection Officer

Message activity and logs viewable by role, 45 days of full content history stated with a customisable seven-to-365-day range, seven webhook event types with a documented six-attempt retry schedule, health tracked per event type with pausing on persistent failure, and a webhook statistics endpoint plus statistics by tag. From my chair the notable gap is integrity, not visibility: the captured pages state webhooks are not signed with HMAC, and we found no public information on alerts for bounce or complaint spikes or on exporting events to a log tool. 2 7 17 18 21

Report an error

Message data, retention & security

How this is scored

What is stored about each message and what the customer controls: whether message bodies are stored or only metadata, retention periods and the setting to shorten them, deletion of a recipient's data on request, open and click tracking that can be switched off per stream or message, TLS for delivery with an option to require it, encryption at rest, API keys with scopes and per-domain restrictions, IP allow-listing, two-factor authentication and SSO for the dashboard, an audit log, a vulnerability disclosure programme, and security certifications or audits with their scope. Where the data is processed and by whom is scored under sovereignty.

0 — Stores every message indefinitely with no controls, and the vendor states it uses message content for its own purposes.

3 — A privacy policy and a statement that data is encrypted; what is stored, retention and access controls are basic or not described.

5 — What is stored per message documented, retention periods stated, open and click tracking switchable, TLS used for delivery, API keys with restricted permissions, two-factor authentication for the dashboard, and a data processing agreement offered.

8 — Message content retention configurable down to none or metadata only, enforced TLS per domain or message, encryption at rest stated, scoped API keys and IP allow-listing, SSO (SAML) and roles, an audit log, deletion of recipient data by API, and ISO 27001 or SOC 2 stated with its scope.

10 — Data minimisation that can be verified: every stored field and its retention listed, content never stored unless the customer opts in, customer-managed encryption keys or equivalent, independent audits published with their scope, and every security control the customer has listed with its effect.

Report an error

The Data Protection Officer

The DPA names what is processed (metadata, email address, message content), content retention is 45 days by default and adjustable from 7 to 365 days, open and click tracking are switchable per message, there are server- and account-level tokens, IP allow-listing, two-factor authentication on every plan that the owner can require, encryption at rest stated, deletion of recipient data through a data removal API, and SOC 2 certified data centres with a SOC 2 report offered as the audit alternative. I must flag two findings before any health data goes near this: the terms state the vendor may view, copy and internally use messaging content to train and improve the service, and outbound TLS is opportunistic, falls back to unencrypted and the customer cannot control the TLS version; we also found no public information on SSO or an audit log. 8 10 13 14 19 20

Report an error

Reliability, accounts & support

How this is scored

Whether the platform can be relied on and run by a team: a public status page with incident history, uptime SLA and service credits published, redundancy or failover across data centres described, queueing and retry of mail during outages, sub-accounts or servers per application, client or tenant, team members with roles, separate environments, support channels and response times per plan, named migration help, and integrations with platforms that send mail on the customer's behalf (WordPress, Shopify, Shopware, Supabase, Vercel and similar).

0 — No status page, no support channel and no way to separate users or applications.

3 — A support contact and a single account; status page, SLA, sub-accounts and roles are basic or not described.

5 — A public status page with incident history, an uptime SLA on at least one plan, sub-accounts or separate servers per application, team members with roles, support by email or chat with stated hours, and plugins or guides for several named platforms.

8 — An SLA with service credits published, redundancy across data centres or regions described, mail queued and retried during incidents, sub-accounts with their own keys, domains and limits manageable by API, granular roles, support response times per plan, and migration assistance offered.

10 — Reliability that can be verified: uptime history published for years, post-mortems for incidents, multi-region failover documented, an SLA covering delivery latency as well as API availability, and white-label or reseller tooling for agencies and platforms.

Report an error

The Data Protection Officer

Separate servers per application with plan limits and up to ten message streams each, three roles with a documented permission matrix plus an observer role, redundant data centres in multiple locations with N+2 redundancy and geographic load balancing, free premium support, migration guides, and WordPress, Zapier and framework integrations. We found no public information on an uptime SLA or service credits, on queueing and retry of mail during incidents, or on support response times per plan, so I cannot take reliability as contractually backed. 1 5 7 21 22

Report an error

European sovereignty

How this is scored

Who the contracting entity and the parent company are, where messages, logs and recipient data are processed and stored, whether an EU region can be chosen and what it covers, and who the subprocessors are (cloud hosting, sending infrastructure, logging, support and payment tools). Independently sourced by the sovereignty pipeline; every message carries personal data, so the whole sending chain counts, not only the dashboard.

0 — Non-EU vendor and contracting entity, hosting unstated, subprocessors unnamed, and no data processing agreement offered.

3 — A privacy policy and a data processing agreement exist, but hosting location is unstated or non-EU and the subprocessors are not listed.

5 — An EU region available and an EU contracting entity or EU representative, but parts of the chain (sending infrastructure, logs, support, payment) run through non-EU providers without a stated safeguard, or the EU region does not cover logs and account data.

8 — EU processing of messages, logs and account data on named infrastructure, an EU contracting entity, subprocessors listed with their locations, a data processing agreement published, and security certifications (ISO 27001, SOC 2) stated.

10 — Sovereign end to end and evidenced: European ownership, entity, hosting, sending infrastructure and every subprocessor, data export and deletion documented, and certifications published with their scope rather than implied.

Report an error

The Data Protection Officer

The contracting entity is AC PM, LLC, an ActiveCampaign company under Illinois law, personal information is stored in AWS data centres, and the terms have the customer consent to processing and storage in the United States and other countries; we found no public information on an EU region covering messages, logs or account data, and the DPA's reliance on the Data Privacy Framework and the Standard Contractual Clauses confirms transfers out of the EEA are contemplated. There are real mitigations — an executable DPA with SCC modules two and three governed by Irish law, DPF certification, an Article 27 EU representative in Germany, and a published sub-processor page with change notifications — but the named sub-processor list with locations was not captured, so I place this between the levels: above a bare DPA, well short of EU processing. 8 9 10 11

Report an error

Pricing transparency

How this is scored

Whether a buyer can compute the real annual cost from public pages alone: price per tier by monthly message volume, the price per additional thousand messages, the free tier and its limits, what dedicated IPs, extra log retention, sub-accounts, SSO and support plans cost, minimum term, and whether unused volume carries over.

0 — No public prices at all; every customer is a sales call.

3 — A starting price or a free tier exists, but how cost scales with volume or which features cost extra is unclear.

5 — Tiers are public with their monthly volume and price, but at least one commonly needed piece (overage rate, dedicated IP, longer log retention, SSO, support plan) is unpriced or "on request".

8 — Every tier priced publicly with its volume and overage rate per thousand messages, dedicated IPs and add-ons priced, log retention per tier stated, minimum term and VAT treatment stated.

10 — Complete price computability: annual cost derivable for a given monthly volume, number of domains and sub-accounts and feature set, with every add-on, support and overage fee and the cancellation terms published.

Report an error

The Data Protection Officer

Four tiers priced publicly with their overage rate per thousand messages (Free at $0.00/mo with 100 emails/month, Basic at $15.00/mo with extras at $1.80/1,000, Pro at $16.50/mo at $1.30/1,000, Platform at $18.00/mo at $1.20/1,000), dedicated IPs at $50/month per IP with no setup fees, DMARC monitoring at $14/month per domain, custom retention starting at $5/month, no rollover of unused email, and monthly auto-renewal cancelled through the service. What stops me going higher: the retention add-on is a starting price rather than a computable figure, high-volume pricing is on request, and we found no public information on VAT treatment. 7 8

Report an error

European sovereignty — proven facts

0 of 6 dimensions proven

Built only from facts shown on the vendor's own pages. A dimension we could not prove is left open, not scored as zero.

Hosting location Not determined ⚠ unverified — uncited Report an error
Hosting options Not determined — uncited Report an error
Open source Not determined — uncited Report an error
Data processing agreement Not determined ⚠ unverified — uncited Report an error
Transfer impact assessment Not determined — uncited Report an error

Questions about Postmark

Is Postmark European?

No. whats-best.ai classifies Postmark as Rest of world.

Where does Postmark store data?

Not stated on the vendor’s pages as of 1 Nov 2026.

Does Postmark have a free plan?

Yes. Postmark has a free plan, per the vendor’s page captured 1 Nov 2026.

What are the best alternatives to Postmark?

As of 1 Nov 2026, the panel rates Lettermint (3.5/5), Bird Email API (formerly SparkPost) (3/5) and Mailjet Email API (3/5) highest among the other 15 Transactional Email products evaluated. Ratings that look equal are rounded to half stars; the order uses the unrounded rating, then the name. The highest-rated European alternative is Lettermint (EU-Made). Ratings are the AI panel’s opinion, formed from public evidence: how scores are made. The full list, with European products first: Postmark alternatives.

Where this could be wrong

What we left out

A claim that does not survive our checks costs us the claim, not the page. This is what was taken off this one.

Do you know more about Postmark? Tell us Report an error on this page

Sources (22)

The pages every claim on this page was read from — each one checked, dated, and kept verifiable.

  1. 1 Vendor homepage postmarkapp.com Checked 1 Nov 2026 Details →
  2. 2 Features page (transactional email) postmarkapp.com Checked 1 Nov 2026 Details →
  3. 3 Features page (SMTP relay) postmarkapp.com Checked 1 Nov 2026 Details →
  4. 4 Features page (message streams) postmarkapp.com Checked 1 Nov 2026 Details →
  5. 5 Features page (deliverability) postmarkapp.com Checked 1 Nov 2026 Details →
  6. 6 API documentation postmarkapp.com Checked 1 Nov 2026 Details →
  7. 7 Pricing page postmarkapp.com Checked 1 Nov 2026 Details →
  8. 8 Terms of service postmarkapp.com Checked 1 Nov 2026 Details →
  9. 9 Privacy policy www.activecampaign.com Checked 1 Nov 2026 Details →
  10. 10 Data processing agreement (dpa) postmarkapp.com Checked 1 Nov 2026 Details →
  11. 11 Security / trust page (EU data protection) postmarkapp.com Checked 1 Nov 2026 Details →
  12. 12 Security / trust page postmarkapp.com Checked 1 Nov 2026 Details →
  13. 13 Sending API, SMTP & developer experience — found from sitemap postmarkapp.com Checked 1 Nov 2026 Details →
  14. 14 Sending API, SMTP & developer experience — found from sitemap postmarkapp.com Checked 1 Nov 2026 Details →
  15. 15 Deliverability & sender reputation — found from sitemap postmarkapp.com Checked 1 Nov 2026 Details →
  16. 16 Deliverability & sender reputation — found from sitemap postmarkapp.com Checked 1 Nov 2026 Details →
  17. 17 Message logs, events & webhooks — found from sitemap postmarkapp.com Checked 1 Nov 2026 Details →
  18. 18 Message logs, events & webhooks — found from sitemap postmarkapp.com Checked 1 Nov 2026 Details →
  19. 19 Message data, retention & security — found from sitemap postmarkapp.com Checked 1 Nov 2026 Details →
  20. 20 Message data, retention & security — found from sitemap postmarkapp.com Checked 1 Nov 2026 Details →
  21. 21 Reliability, accounts & support — found from sitemap postmarkapp.com Checked 1 Nov 2026 Details →
  22. 22 Reliability, accounts & support — found from sitemap postmarkapp.com Checked 1 Nov 2026 Details →