--- title: "Is Posteo Safe? No Personal Data, but Encryption Is Opt-In" date: "2026-11-11" author: "Ahsan Luqman" canonical_url: "https://aliasfleet.com/blog/is-posteo-safe" tags: ["Email Privacy", "Secure Email", "Posteo"] description: "Posteo is a €1-a-month German email service built on data minimisation: no personal data at signup, no IP logs, and optional encryption, with clear limits." --- # Is Posteo Safe? No Personal Data, but Encryption Is Opt-In Posteo is a €1-a-month German email service built on data minimisation: no personal data at signup, no IP logs, and optional encryption, with clear limits. Posteo is a German email service that charges €1 per month for a mailbox built on data minimisation. Signup needs a username, a password and a choice of domain only, with no personal data collected and no IP addresses logged. End-to-end encryption is opt-in, not automatic, and Posteo does not support custom domains. The account includes 4 GB of storage and three aliases, with no free tier and no advertising. ## Background and pricing Posteo e.K. is based in Berlin and was founded in 2009, with servers in data centres in Frankfurt, Germany. The company is financed entirely by its users, with no investors and no advertising, and the [feature list](https://posteo.de/en/site/featurelist) states that the price has been stable at €1 per month since 2009. An account can be cancelled at any time, with remaining credit refunded. Posteo reported more than half a million accounts in 2025, a figure given in its [transparency report](https://posteo.de/en/site/transparency_report). The account is a standard mailbox with webmail and support for IMAP, POP3, CalDAV and CardDAV, so it works with external mail clients. The [feature list](https://posteo.de/en/site/featurelist) lists 4 GB of storage, expandable to 75 GB at €0.25 per GB per month, three aliases expandable to 25 at €0.10 per alias per month, and three calendars. An S/MIME certificate for signing and encrypting mail costs €3.65 per year. Storage was doubled from 2 GB to 4 GB on 4 February 2026 at no extra cost, according to the [Posteo blog](https://posteo.de/en/blog/2). The account costs €1 per month, paid in advance from a prepaid credit balance, with no contract and a 14-day notice period. The included items are 4 GB of storage, three aliases, three calendars, an address book, notes, spam and virus protection, and free support by email. Extra calendars cost €0.10 per month each. There is no free tier and no free trial. ## Signup and data minimisation Posteo collects no personal data at signup. The feature list states registration without personal data, no IP logging on the website or the email account, IP stripping from outgoing mail, and no connection of payment data to email accounts. An account is created with a username and a password only, with no name, address, phone number or recovery email required. Independent testing by [email-tools.me](https://www.email-tools.me/posts/posteo-review/) found the same result: the signup form asked for a username, a password and a choice of domain, and nothing else. Payment is handled separately from the account. Posteo accepts bank transfer, PayPal, credit card and cash sent by post. [CyberInsider](https://cyberinsider.com/email/reviews/posteo/) reports that Posteo manually separates payment information from the account record, and [ProPrivacy](https://proprivacy.com/email/review/posteo) notes the cash-by-post option and a 14-day money-back guarantee. ## Encryption and crypto mail storage Transport encryption is automatic. The [encryption page](https://posteo.de/en/site/encryption) states that all access to Posteo is encrypted, with TLS 1.2 to 1.3 and Perfect Forward Secrecy, HSTS and DANE/TLSA, and that mail sent to other providers travels over an encrypted connection when the other server supports it. Posteo reports an A+ mark on the Qualys SSL Labs test as of July 2026. All server hard disks are fully encrypted with dm-crypt/LUKS, and internal connections are encrypted with SSH and TLS. Mail is stored readable on Posteo servers unless crypto mail storage or end-to-end encryption is switched on. A new account has neither feature active by default. End-to-end encryption is opt-in. The encryption page states that individual emails can be given end-to-end encryption with S/MIME or OpenPGP, that both communication partners need to use the encryption, and that message metadata such as subject, recipient, sender and time stamp remain unencrypted. In February 2026 Posteo released its own S/MIME add-on for webmail, described in the [Posteo blog](https://posteo.de/en/blog/new-posteo-smime-add-on-available-now), which had two security audits by independent experts at Cure53 and keeps private keys on the user device. Posteo also offers inbound encryption, which encrypts newly arriving mail with S/MIME or OpenPGP when the sender has not already done so. Crypto mail storage is a separate optional feature. When it is activated, Posteo encrypts all saved emails, including content, attachments and metadata, using RSA asymmetric encryption, AES with HMAC for symmetric encryption and authentication, and bcrypt hashing, with the key protected by the account password. The [encryption page](https://posteo.de/en/site/encryption) states that the feature passed an external audit by Cure53 and that Posteo cannot deactivate the encryption once it is switched on. Calendar and address book data can be encrypted separately with AES, also protected by the account password. Without crypto mail storage or end-to-end encryption, mail is stored readable on Posteo servers, as it is with most conventional providers. ## Transport security and account protection Posteo holds certification for secure email transport from the BSI, the German Federal Office for Information Security, under technical guideline TR-03108 version 2 (2025), according to Posteo. A comparison by [EuropeanStack](https://www.europeanstack.io/en/compare/gmx_mail-vs-posteo) gives the certificate number as BSI-K-TR-0745-2025, though that number was not found on the Posteo pages read for this article. Posteo implemented DANE/TLSA in May 2014 and states on its encryption page that it was the first provider to do so. Two-factor authentication is available using TOTP, with a one-time password that changes every 30 seconds, and the feature list also lists app passwords and passkeys, with up to five of each. An additional account protection setting blocks access by external programs using the main Posteo password, so only app passwords work. The encryption page notes that passwords are stored as salted hashes and that Posteo does not know the account password. The [PrivacyPick review](https://privacypick.com/email/posteo/) states that the audit trail has not been refreshed since 2017, and a full independent audit of the current Posteo codebase was not found in this research. The Cure53 audits cited in this article are feature-specific: crypto mail storage and the S/MIME add-on. ## Transparency report and authority requests Posteo published a transparency report in May 2014, becoming the first German telecommunications provider to do so, and has published one annually since. The [transparency report](https://posteo.de/en/site/transparency_report) covers all authority requests received up to the end of December 2025. Posteo operates under German law, and the German Telecommunications Act has applied to email services since 1 December 2021, after a period from June 2019 to November 2021 when an EU court ruling had removed that obligation. | Request type in 2025 | Count | | :--- | :--- | | Requests for user information | 72 | | Mailbox seizures | 4 | | Surveillance orders for a specified period | 2 | | Unclear requests | 7 | | Total requests | 85 | In 2025 Posteo received 85 requests: 79 from German authorities and 6 from foreign authorities. Posteo lawyers checked the formal correctness of the requests and found 27 of the 72 user information requests formally incorrect. The releases in 2025 were 0 for user information, 0 for traffic data, and content data from 2 mailboxes, both under formally correct judicial rulings. None of the four seizure orders was carried out: three of the mailboxes did not exist and crypto mail storage was activated for one of them. With no personal data or traffic data held, mailbox content is the only data that can be handed over under a court order, and only from mailboxes that exist and are not protected by crypto mail storage. No public breach of Posteo itself was found in the research for this article. That is absence of a public record, not proof that no breach has happened. An address can be checked on [Have I Been Pwned](https://haveibeenpwned.com/). The companion trust pieces on [GMX Mail](https://aliasfleet.com/blog/is-gmx-mail-safe), [AOL Mail](https://aliasfleet.com/blog/is-aol-mail-safe) and [mail.com](https://aliasfleet.com/blog/is-mail-com-safe) cover large free providers whose safety turns on the security stack rather than on data minimisation. ## Custom domain availability Posteo does not support custom domains. The [PrivacyPick review](https://privacypick.com/email/posteo/) states that the only choice is between Posteo domains, and [EuropeanStack](https://www.europeanstack.io/en/compare/posteo-vs-swissnode) describes the refusal as deliberate, to avoid the identity records that domain ownership would require. That reason comes from independent reviews rather than from a Posteo page read for this article. A business or a person who needs an address on a domain they own cannot use Posteo for it, and the address cannot be moved to another provider if Posteo is left. Posteo also has no free tier, and no recovery route that works without the account password when crypto mail storage is active, since Posteo cannot read the encrypted data to restore it. ## AliasFleet and Posteo [AliasFleet](https://aliasfleet.com) creates managed, persistent email aliases that forward to a mailbox, so the mailbox address is not shared with websites or services. A Posteo mailbox works as the destination for those aliases, and the Posteo address stays private while each website or service gets its own alias. If one alias starts receiving spam or appears in a breach, that alias can be paused or closed without touching the Posteo account or any other alias. The same pattern is described in the companion trust pieces on [Gmail](https://aliasfleet.com/blog/is-gmail-safe) and [Outlook](https://aliasfleet.com/blog/is-outlook-safe), and in the guide to [whether email aliases are safe](https://aliasfleet.com/blog/are-email-aliases-safe). Posteo already offers three aliases inside one account, but those are tied to the Posteo account and to Posteo domains, while AliasFleet aliases sit in front of the mailbox and can be managed independently of it. The [AliasFleet documentation](https://aliasfleet.com/docs) explains how aliases forward and how replies are routed, and pricing is on the [AliasFleet pricing page](https://aliasfleet.com/pricing). Posteo holds no personal data, no IP addresses and no payment data connected to the account. Mail in an unprotected mailbox can be obtained under a court order, and Posteo does not support custom domains.