ProtonMail servers and data security All ProtonMail servers are physically located in Switzerland in secure facilities. This means user data is protected by Swiss law, which generally provides for better privacy than USA or EU law. However, ProtonMail makes it clear that they will turn over whatever information they have on you to the Swiss authorities if ProtonMail believes you might be violating Swiss laws. This is where the lack of encryption for the Subject line of messages can become a problem. … [Read more...] about ProtonMail review: Is secure email really secure?