Fastmail vs Posteo Comparison

Feature	Fastmail Visit →	Posteo Visit →
Overview
Rating	6.8	6.1
Pricing	$5.00/moIndividual (monthly) $5.00/moIndividual (annual) $8.00/moDuo (annual) $11.00/moFamily, up to 6 (annual) Show billing detailsHide billing details Individual (monthly): US$5/mo Individual (annual): US$60 for 12 months Duo (annual): US$96 for 12 months Family, up to 6 (annual): US$132 for 12 months	$1.00/moStandard (individual, monthly) Show billing detailsHide billing details Standard (individual, monthly): EUR 1/month, prepaid credit, no annual commitment
Free tier	Paid only	Paid only
Established	1999	2009
Platforms	WindowsmacOSLinuxAndroidiOS	Not specified
Privacy
Jurisdiction	Australia Show detailsHide details Fastmail Pty Ltd, PO Box 234, Collins St West, VIC 8007, Australia, ABN 31 142 646 580, headquartered in Melbourne. Also operates Fastmail US LLC, a satellite office at 1429 Walnut Street, 12th Floor, Philadelphia, PA 19102, USA. Independent and employee-owned — not venture-backed or acquired by a larger group.	Germany Show detailsHide details Posteo e.K. (a registered sole proprietorship), Methfesselstr. 38, 10965 Berlin. Registered at the Handelsregister Berlin-Charlottenburg, HRA 47592 B. Founded and owned by Patrik and Sabrina Löhr, self-financed with no external investors or debt.
Independent security audit	None on record	Cure53 2017 Show audit detailsHide audit details Posteo web application, including Calendar and Notes (a separate, earlier Cure53 test in April 2015 covered Crypto Mail Storage specifically)
Source code	Partly open source	Partly open source
Zero-access encryption	No	Yes
Intra-provider E2EE	No	No
External PGP	Manual import	Native
Past data breach	No	No
Telemetry	On unless you opt out	No telemetry
Features
Hosting	Cloud	Cloud
Custom domain support	Yes	No
Aliases	Unlimited	Limited
Anti-spam approach	Connection-level blocking of known spam-sending infrastructure before a message is accepted, followed by content-based scoring of accepted mail with a threshold that routes high-scoring messages to Spam; the filter adapts per user from Report spam / Not spam / delete / archive actions. Documented on the vendor's own Stop Spam help page as analysing message content server-side, consistent with a provider that holds the encryption keys and makes no zero-access claim.	Described by Posteo only as a 'highly efficient spam and virus filter' — no further technical methodology is publicly documented.
Bundled services	CalendarContactsFiles	CalendarAddress BookNotes