Best Postmark alternatives in 2026
Postmark has the best-regarded deliverability record in transactional email, but its free plan holds 100 emails a month and it has no audience or campaign tools. For teams that want marketing email in the same place, the best Postmark alternative is Unitpost: one API and bill for both, a 5,000-email free plan and a one-key import. Resend suits developers who only send transactional mail.
Updated November 2, 2026. We make Unitpost, and it is on this list. Every score has a reason and the weights are published below, so you can re-rank it for your own needs. How we scored
| # | Product | Best for | Score |
|---|---|---|---|
| 1 | Unitpost | app teams sending both kinds of email | 4.3 |
| 2 | Brevo | marketers who want a full suite | 3.7 |
| 3 | Resend | developer-first transactional email | 3.6 |
| 4 | Mailgun | high-volume senders and validation | 3.0 |
| 5 | SendGrid | enterprises and multi-tenant platforms | 2.8 |
| 6 | MailerSend | a cheap first paid plan | 2.7 |
| 7 | Amazon SES | lowest cost at very high volume | 2.5 |
Why teams look for a Postmark alternative
- The free plan is 100 emails a month.
- Bulk mail runs on broadcast streams, with no audience or campaign tools.
- Inbound email isn't on the Basic plan.
When Postmark is still the better choice
- A missed email is expensive: banking password resets, MFA codes, booking confirmations
- You want transactional sending physically isolated from anything marketing-shaped
- You are willing to pay a premium specifically for inbox placement
What moves when you leave Postmark
With Unitpost's Migration Assistant and one Postmark key:
- Contacts: rebuild. Postmark stores no contacts or lists, so nothing imports. If you start campaigns here, import contacts from your own database with
POST /api/v1/contacts/imports. - Unsubscribes and consent: partly imports. Postmark records unsubscribes and manual blocks as
ManualSuppressionon one stream. They import as workspace suppressions that stop every send, so a broadcast unsubscriber would stop getting password resets until step 2. - Suppressions (bounces and complaints): imports. Hard bounces and spam complaints from every stream on every server import with their reason. Complaint rows cannot be removed here, as at Postmark.
- Segments or lists: rebuild. Postmark has no lists or segments. Create segments here when you start campaigns.
- Topics: rebuild. Postmark has no topics. Create them here if you want per-category opt-outs on campaigns.
- Templates: partly imports. Subject, HTML and text import as draft code-mode templates in the marketing category. Layouts arrive as separate templates and are not merged into the templates that use them; same-named templates from two servers get a
(2)suffix. - Sending domains: partly imports. With an Account API token, each domain is recreated as verifying with a new DKIM key. A server token cannot read domains, and sender signatures (single verified addresses) are not read.
- Webhooks: partly imports. Each server's webhooks import with their enabled triggers, switched off and with a new signing secret. HTTP auth credentials and custom headers set on them are not copied.
- API keys and tokens: rebuild. Server and account tokens stay at Postmark. Create Unitpost API keys instead.
- Automations and broadcasts: rebuild. Postmark has no automations to move. Broadcasts sent from your code become campaigns here, which need contacts and a segment.
- Message streams: rebuild. Unitpost has no streams. A template's
category(transactionalormarketing) decides footers and opt-outs, broadcasts become campaigns, and the inbound stream becomes receiving on a verified domain.
The picks
#1 · 4.3 / 5
Unitpost
Best for app teams sending both kinds of emailTransactional and marketing email on one API, one contact list and one bill, with a permanent free plan and an importer for six providers.
Pros
- Permanent free plan, no card
- Imports suppressions (bounces and complaints) from Postmark with one key
- REST API, SMTP relay, MCP server and nine SDKs on every plan
- Unlimited contacts on paid plans, priced by sends
Cons
- A newer sender, without a long public track record
- No sub-accounts, and dedicated IPs are not launched yet
- SMS is on paid plans only
- Free plan
- 5,000 emails a month, 200 a day, no card
- Paid from
- $10 a month for 20,000 emails
- Priced by
- Emails sent
#2 · 3.7 / 5
Brevo
Best for marketers who want a full suiteA marketing suite with email, SMS, WhatsApp, a CRM and automation, plus a transactional API and SMTP relay. Its free plan sends the most email here.
Pros
- The largest free volume: 300 emails a day
- CRM, landing pages and automation built in
- Paid plans sized by email volume, from $9 a month
Cons
- SMS and WhatsApp credits are bought separately
- A large step in price from Standard to Professional
- Free plan
- 300 emails a day
- Paid from
- $9 a month for 5,000 emails
- Priced by
- Emails sent
#3 · 3.6 / 5
Resend
Best for developer-first transactional emailA clean, modern email API from the team behind React Email, with inbound email and an official MCP server on every plan. Marketing contacts are billed on a separate plan.
Pros
- A modern API with clear errors and many SDKs
- Inbound email on every plan, free included
- React Email for building templates in code
Cons
- Marketing is a second plan, priced by contacts ($40 a month for 5,000)
- Free sending is capped at 100 emails a day
- Free plan
- 3,000 emails a month, 100 a day
- Paid from
- $20 a month for 50,000 emails
- Priced by
- Sends and contacts
#4 · 3.0 / 5
Mailgun
Best for high-volume senders and validationA long-running email API with address validation and inbox placement testing. Strong at volume, with marketing campaigns left to other tools.
Pros
- Email validation and inbox placement testing
- EU region for data residency
- Proven at very high volume
Cons
- The free plan keeps logs for one day, on one domain
- Marketing campaigns need another tool
- Free plan
- 100 emails a day on one domain
- Paid from
- $15 a month for 10,000 emails
- Priced by
- Emails sent
#5 · 2.8 / 5
SendGrid
Best for enterprises and multi-tenant platformsThe long-running email API, now part of Twilio, with Marketing Campaigns as a separate product. Strong at scale; there is no free plan any more.
Pros
- Proven at very high volume
- Sub-accounts for multi-tenant platforms
- Dedicated IPs from the Pro plan
Cons
- No free plan: a 60-day trial, then from $19.95 a month
- Marketing Campaigns is a separate product and plan
- Free plan
- None: a 60-day trial at 100 emails a day
- Paid from
- $19.95 a month (Essentials)
- Priced by
- Sends and contacts
#6 · 2.7 / 5
MailerSend
Best for a cheap first paid planA transactional email API with an official hosted MCP server and a $7 first paid plan. The free plan is small.
Pros
- Hobby is $7 a month for 5,000 emails
- API and SMTP on the free plan
- An official hosted MCP server
Cons
- 500 emails a month on free
- No audience or campaign tools
- Free plan
- 500 emails a month, card required
- Paid from
- $7 a month for 5,000 emails
- Priced by
- Emails sent
#7 · 2.5 / 5
Amazon SES
Best for lowest cost at very high volumeAmazon's sending service, inside AWS: the lowest price per email here. You build the rest yourself, from bounce handling to templates and dashboards.
Pros
- $0.10 per 1,000 emails on pay-as-you-go pricing
- Runs inside your AWS account and IAM
- Inbound email as well as sending
Cons
- No campaign builder or audience tools
- Bounce handling, dashboards and reputation work are yours
- Free plan
- None for SES; new AWS accounts get up to $200 in credits
- Paid from
- $0.10 per 1,000 emails (new accounts start on a $0.16 plan)
- Priced by
- Emails sent
Scores side by side
| Product | Free plan20% | Developer experience20% | Transactional + marketing20% | Switching15% | Deliverability15% | Scale10% | Total |
|---|---|---|---|---|---|---|---|
| Unitpost | 5 | 5 | 5 | 4 | 3 | 2 | 4.3 |
| Brevo | 5 | 3 | 5 | 2 | 3 | 3 | 3.7 |
| Resend | 4 | 5 | 3 | 3 | 3 | 3 | 3.6 |
| Mailgun | 3 | 3 | 2 | 2 | 4 | 5 | 3.0 |
| SendGrid | 1 | 3 | 3 | 2 | 4 | 5 | 2.8 |
| MailerSend | 2 | 4 | 2 | 2 | 3 | 3 | 2.7 |
| Amazon SES | 2 | 3 | 1 | 2 | 3 | 5 | 2.5 |
How we scored
This list is for teams sending app email through Postmark who are weighing a switch. What matters to them: a free or cheap way to keep sending, a modern API, marketing email in the same place, and a move that keeps suppressions.
- Free plan (20%). A permanent free plan large enough to run a small app on, with no card.
- Developer experience (20%). A clear REST API, current SDKs, readable errors and docs.
- Transactional + marketing (20%). Both kinds of email in one product, on one contact list and one bill.
- Switching (15%). An importer, or a documented path, that moves Postmark contacts, suppressions and templates.
- Deliverability (15%). A long public record of inbox placement, and the tooling to protect it.
- Scale (10%). Proven at very high volume, with dedicated IPs and enterprise plans.
Each product gets 1 to 5 per criterion, from its own pricing and docs pages. The total is the weighted mean, so changing a weight re-ranks the list.
Why Unitpost scored 4.3
- Free plan: 5/5. 5,000 emails a month free for good, 200 a day, no card.
- Developer experience: 5/5. Bearer-token REST API, nine SDKs, a CLI and an MCP server, with idempotency keys on sends.
- Transactional + marketing: 5/5. Campaigns, segments and topics share the contact list and the bill with API sends.
- Switching: 4/5. The Migration Assistant imports suppressions (bounces and complaints) from Postmark with one key; the guide covers the rest.
- Deliverability: 3/5. Guided SPF, DKIM and DMARC with continuous checks, but a short public record so far.
- Scale: 2/5. No sub-accounts, and dedicated IPs are not launched yet.
Checked November 2, 2026 against unitpost.com/pricing, unitpost.com/sms, registry.npmjs.org/unitpost.
Why Brevo scored 3.7
- Free plan: 5/5. 300 emails a day, about 9,000 a month, on a permanent free plan.
- Developer experience: 3/5. A full API and SMTP relay, shaped by the marketing suite rather than built for developers first.
- Transactional + marketing: 5/5. Campaigns, automation and transactional sending in one account.
- Switching: 2/5. No importer or guide for Postmark found; contacts move by CSV and the rest by API.
- Deliverability: 3/5. An established sender, without Postmark's public time-to-inbox record.
- Scale: 3/5. Professional plans from 150,000 emails; the focus is marketing teams more than high-volume APIs.
Checked November 2, 2026 against brevo.com/pricing/, developers.brevo.com/docs/mcp-protocol, help.brevo.com/hc/en-us/articles/7959631848850, help.brevo.com/hc/en-us/articles/360021533839, registry.npmjs.org/@getbrevo/brevo.
Why Resend scored 3.6
- Free plan: 4/5. 3,000 emails a month free, capped at 100 a day.
- Developer experience: 5/5. The API many newer providers copy, with SDKs across most languages.
- Transactional + marketing: 3/5. Broadcasts exist, but marketing contacts sit on a second plan and bill.
- Switching: 3/5. A published guide for moving from Postmark; no importer, so data moves by CSV and API.
- Deliverability: 3/5. A shorter public record than SendGrid or Postmark.
- Scale: 3/5. Higher-volume plans above Pro; less proven at the very largest volumes.
Checked November 2, 2026 against resend.com/pricing, resend.com/migrate, resend.com/docs/dashboard/receiving/introduction, github.com/resend/mcp-send-email, resend.com/docs/send-with-smtp, resend.com/docs/api-reference/api-keys/create-api-key, registry.npmjs.org/resend, resend.com/docs/dashboard/webhooks/retries-and-replays.
Why Mailgun scored 3.0
- Free plan: 3/5. A free plan of 100 emails a day on one domain, with one day of logs.
- Developer experience: 3/5. A capable API on HTTP Basic auth, with a surface shaped by long history.
- Transactional + marketing: 2/5. Built for transactional sending; marketing campaigns need another product.
- Switching: 2/5. No importer or guide for Postmark found; contacts move by CSV and the rest by API.
- Deliverability: 4/5. Validation, inbox placement tests and dedicated IPs.
- Scale: 5/5. Built for very high volume, with dedicated IP pools and enterprise plans.
Checked November 2, 2026 against mailgun.com/pricing/, mailgun.com/resources/guides/migrating-from-sendgrid-to-mailgun-email-api/, documentation.mailgun.com/docs/mailgun/mcp, documentation.mailgun.com/docs/mailgun/user-manual/sending-messages/send-smtp, registry.npmjs.org/mailgun.js, documentation.mailgun.com/docs/mailgun/user-manual/receive-forward-store/receive-http.
Why SendGrid scored 2.8
- Free plan: 1/5. No free plan: a 60-day trial at 100 emails a day, then from $19.95 a month.
- Developer experience: 3/5. A large API with SDKs, shaped by a decade of backwards compatibility.
- Transactional + marketing: 3/5. Marketing Campaigns is a separate product with its own plans.
- Switching: 2/5. No importer or guide for Postmark found; contacts move by CSV and the rest by API.
- Deliverability: 4/5. A long track record, with dedicated IPs from the Pro plan.
- Scale: 5/5. Proven at very high volume, with sub-accounts and enterprise support.
Checked November 2, 2026 against twilio.com/en-us/products/email-api/pricing, twilio.com/docs/sendgrid/for-developers/sending-email/integrating-with-the-smtp-api, twilio.com/docs/sendgrid/ui/analytics-and-reporting/email-activity-feed, registry.npmjs.org/@sendgrid/mail, twilio.com/docs/sendgrid/for-developers/parsing-email/inbound-email.
Why MailerSend scored 2.7
- Free plan: 2/5. 500 emails a month on one domain.
- Developer experience: 4/5. A modern REST API, SMTP and an official MCP server.
- Transactional + marketing: 2/5. Built for transactional email; bulk sending comes on paid plans, without audience tools.
- Switching: 2/5. No importer or guide for Postmark found; contacts move by CSV and the rest by API.
- Deliverability: 3/5. An established sender, without a long public inbox-placement record.
- Scale: 3/5. Plans for growing volume; fewer enterprise tools than the incumbents.
Checked November 2, 2026 against mailersend.com/pricing, developers.mailersend.com/mcp, mailersend.com/help/smtp-relay, mailersend.com/features/inbound-emails, developers.mailersend.com/api/v1/webhooks.html, registry.npmjs.org/mailersend, developers.mailersend.com/api/v1/inbound.
Why Amazon SES scored 2.5
- Free plan: 2/5. No SES free tier; new AWS accounts get up to $200 in credits.
- Developer experience: 3/5. AWS SDKs and IAM: powerful, with more setup than an email API.
- Transactional + marketing: 1/5. A sending service; it has no campaign builder.
- Switching: 2/5. No importer or guide for Postmark found; contacts move by CSV and the rest by API.
- Deliverability: 3/5. Good infrastructure, but reputation monitoring is your job.
- Scale: 5/5. AWS-scale throughput and dedicated IPs.
Checked November 2, 2026 against aws.amazon.com/ses/pricing/, docs.aws.amazon.com/ses/latest/dg/smtp-connect.html, docs.aws.amazon.com/ses/latest/dg/smtp-credentials.html, docs.aws.amazon.com/ses/latest/dg/vdm-dashboard.html, registry.npmjs.org/@aws-sdk/client-sesv2, docs.aws.amazon.com/ses/latest/dg/receiving-email-notifications-contents.html.
Frequently asked questions
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