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Mailboxes and webmail

EU-hosted email hosting with a built-in webmail client. Create mailboxes on your domain, read and send from the dashboard, or connect any IMAP or POP3 client.

Webmail included

Read, compose, reply, and organise email in the PostStack dashboard. Folders, flags, attachments, and storage quotas are handled without an external client.

Standards-based hosting

Every mailbox is available over IMAP and POP3. Connect Thunderbird, Apple Mail, Outlook, or Gmail. Autodiscovery configures clients with one click.

One provider for everything

Send through the API, receive in mailboxes, and manage in webmail, all on the same EU infrastructure with TLS enforced on every connection.

Create a mailbox

typescript
await poststack.mailboxes.create({
  address: 'support@yourdomain.com',
  password: 'secure-password',
  displayName: 'Support Team',
});

Use cases

Customer support inbox

Create `support@yourdomain.com` and `help@yourdomain.com`. Replies route to the PostStack webmail, your team replies directly, and the threading stays intact in the customer’s inbox.

Founder and team personal mail

Run `michael@yourcompany.com` as a real IMAP mailbox while sending transactional email through the same PostStack account. Two products on one credential, one domain, one bill.

Inbound reply handling for newsletters

Configure the newsletter `Reply-To` to land in a real mailbox rather than vanishing into a webhook. Read and reply from webmail or any IMAP client.

Programmatic inbox processing

Combine mailboxes with inbound webhooks to fan email out to multiple downstream systems — store in your database, raise a support ticket, post to Slack, all triggered from a single received message.

How it works

PostStack mailboxes are real IMAP/POP3 mailboxes backed by Dovecot, running on the same EU infrastructure as the API. Create a mailbox under any verified domain and use it as a normal email account — IMAP on port 993 (TLS), POP3 on port 995 (TLS), SMTP submission on port 465 (TLS). Email clients like Thunderbird, Apple Mail, Outlook, and Gmail (via fetch) connect directly. Autoconfig endpoints at `/.well-known/autoconfig/mail/config-v1.1.xml` and the Microsoft Autodiscover XML let supported clients set up automatically by typing only the email address and password. The PostStack dashboard includes a built-in webmail UI: read, compose, reply, forward, attach, organise into folders, search, and use keyboard shortcuts (Gmail-style: j/k/r/a/f/e). The webmail uses IDLE so new mail appears within a second of arrival without polling. Inbound messages are fully delivered to the mailbox — there is no API-only "inbound" mode that requires special webhook handling. Spam filtering uses Rspamd with the same heuristics, RBL lookups, and DKIM/SPF/DMARC verification that protect Fastmail-class providers. Storage is per-mailbox quota: every mailbox includes 1 GB in its €1/mo fee and can be expanded up to 50 GB at €1/GB/mo. Mailbox passwords are bcrypt-hashed and managed separately from the team password so a compromised webmail password does not expose your PostStack admin account.

Frequently asked questions

Are these real IMAP mailboxes?

Yes — backed by Dovecot, accessible via IMAP, POP3, and SMTP submission. Connect Thunderbird, Apple Mail, Outlook, or Gmail. Autoconfig is wired up so most clients set up with just an email and password.

Can I use my own domain?

Yes. Verify a domain for sending (SPF/DKIM/DMARC), then add a single MX record pointing at PostStack and you can create mailboxes on that domain.

How is spam filtered?

PostStack runs Rspamd with RBL lookups, DKIM/SPF/DMARC verification, Bayesian classification, and TLS-RPT/MTA-STS. Filtering quality is comparable to Fastmail or ProtonMail.

Is webmail included?

Yes. A keyboard-driven webmail UI is part of the PostStack dashboard. Compose, reply, search, folder management, attachments, threading — no external client required.

Can I send from mailboxes?

Yes. Each mailbox supports outbound SMTP submission on port 465 (TLS). The same DKIM signing and deliverability machinery the API uses applies to mailbox sends.

What about quotas?

Each mailbox includes 1 GB of storage in its €1/mo fee and can be expanded up to 50 GB at €1/GB/mo. Quotas are soft — incoming mail above quota is held and delivered when space frees up rather than bounced.

Related features

Ready to start sending?

Free plan includes 3,000 emails/month. No credit card required.