Encryption16 of 27
Trust and audits8 of 26
Apps and access8 of 18
Mailbox7 of 13
Price10 of 16
encrypted email service · Heinlein Support
mailbox.org
German mailbox with optional OpenPGP encryption, standard IMAP access and plans from €1 a month.
In short
- Light costs €1 a month on a 12-month term, with 2 GB of mail storage1.
- Standard costs €3 a month on yearly billing, with 20 GB and your own domain1.
- Mail is served over IMAP and SMTP to Outlook, Thunderbird and Apple Mail6.
- Encryption of stored mail is an optional Guard setting; existing mail is left as it is when you switch it on3.
- There is no permanent free plan, only a 30-day trial1.
mailbox.org suits people who want a low-cost mailbox that works in standard mail programs, with encryption they switch on1,3,6. Standard at €3 a month adds 20 GB and a custom domain1. The catch: encryption is opt-in and applies to new incoming mail, and it has no free plan or official mail app1,3,6.
Best for: People who want to read their mail in Thunderbird or Outlook and switch on encryption themselves.
Where the points come from
Encryption 16 of 27 points
| Rule | What is published | Points |
|---|---|---|
| Stored mail the provider cannot read | YesOptional: Guard encrypts new incoming mail; its key is decrypted only with your Guard password, which mailbox.org does not store3,4. | 10 / 10 |
| Automatic end-to-end encryption between its own users | Not publishedNot published on the vendor's Guard help pages3,4. | 0 / 8 |
| Encrypted mail to other providers | YesGuard sets up a temporary mailbox on mailbox.org for recipients without a PGP key5. | 6 / 6 |
| Encrypted contacts or calendar | Not publishedNot published on the vendor's address book and calendar help page10. | 0 / 3 |
Trust and audits 8 of 26 points
| Rule | What is published | Points |
|---|---|---|
| Independent audit since 2024 | Not publishedNot published on the vendor's security page, which names no outside firm or audit report9. | 0 / 8 |
| Open-source apps | Not publishedNot published on the vendor's home or security pages2,9. | 0 / 6 |
| SOC 2 Type II or ISO 27001 | YesThe home page says the service is backed by ISO 27001 certification and BSI C5 attestation2. | 4 / 4 |
| Transparency report | YesThe Transparency Report 2025, dated 10 February 2026, counts 74 requests from authorities, 18 rejected7. | 4 / 4 |
| Security key for two-factor sign-in | Not publishedNot published: help pages describe authenticator-app codes and YubiKey one-time passwords, with no FIDO2 or WebAuthn8,11. | 0 / 4 |
Apps and access 8 of 18 points
Mailbox 7 of 13 points
| Rule | What is published | Points |
|---|---|---|
| Your own domain | YesStandard and Premium let you use your own domain1. | 5 / 5 |
| Mail storage on the cheapest paid plan | 2Light, the cheapest paid plan, has 2 GB of mail storage1. | 2 / 5 |
| Export your whole mailbox | Not publishedNot published: the backup page describes saving selected messages as .eml files, not the whole mailbox6. | 0 / 3 |
Price 10 of 16 points
The rule behind each line: how we score encrypted email services.
Plans and prices
As the vendor lists them, before tax. Prices are in US dollars unless the plan shows euros; the points use US dollars, with euros converted at the ECB rate.
| Plan | Price as listed | Per month | Notes |
|---|---|---|---|
| Light1 person | €12/year1 | $1.12 | 2 GB mail, no Drive; one-year minimum term; own domain only in family accounts |
| Standard1 person | €36/year1 | $3.36 | 20 GB mail, 10 GB Drive, own domain with 50 aliases; €4 a month on monthly billing |
| Premium1 person | €108/year1 | $10.07 | 50 GB mail, 100 GB Drive, own domain with 250 aliases; €12 a month on monthly billing |
Prices are shown in euros and include VAT at the user's country rate1.
Strengths
- Works in desktop mail programs over IMAP and SMTP6.
- Guard encrypts incoming mail with a key that mailbox.org cannot open without your Guard password3,4.
- Sends encrypted mail to people without PGP through a temporary mailbox5.
- Publishes a transparency report; the 2025 report counts 74 requests7.
- Says it holds ISO 27001 certification2.
Limits
- Encrypting stored mail is a setting; existing mail is unaffected and the Sent folder is not stored encrypted3.
- No permanent free plan; the trial lasts 30 days1.
- Light has 2 GB and a one-year minimum term1.
- The help pages list no mailbox.org mail app and describe two-factor with authenticator-app or one-time-password codes6,8,11.
What Heinlein Support says
Vendor claims. We show them, but they earn no points.
- mailbox.org says it stores data in certified German data centres2.
Other encrypted email services
- 1
Proton MailPeople who want a free encrypted mailbox that grows into a paid one with custom domains and Outlook or Thunderbird access85/100$3.99/mocheapest paid plan - 2
Tuta MailPeople who want contacts and calendar encrypted too, and are fine using Tuta's own apps instead of a mail program73/100$3.36/mocheapest paid plan - 3
Forward EmailPeople with their own domain who want IMAP access and a low price56/100$3/mocheapest paid plan - 5
Atomic MailPeople who want a free encrypted mailbox and apps on four systems47/100$5/mocheapest paid plan
Sources
- mailbox.org prices, mailbox.org. Accessed 8 Oct 2026.
- mailbox.org home page, mailbox.org. Accessed 8 Oct 2026.
- Encrypting incoming emails, mailbox.org. Accessed 8 Oct 2026.
- How is the private key protected?, mailbox.org. Accessed 8 Oct 2026.
- Sending encrypted emails with Guard, mailbox.org. Accessed 8 Oct 2026.
- Data interfaces, mailbox.org. Accessed 8 Oct 2026.
- Transparency Report 2025, mailbox.org. Accessed 8 Oct 2026.
- Setting up two-factor authentication in mailbox, mailbox.org. Accessed 8 Oct 2026.
- Security, mailbox.org. Accessed 8 Oct 2026.
- Address book and calendar, mailbox.org. Accessed 8 Oct 2026.
- YubiKey: webmail with one-time passwords, mailbox.org. Accessed 8 Oct 2026.
- Euro foreign exchange reference rates: US dollar, European Central Bank. Accessed 8 Oct 2026.
Website: mailbox.org/en · Markdown version · We are not affiliated with Heinlein Support.