There are many good reasons to prefer using an email service that supports encryption. Perhaps you need to send confidential information that you don't want anyone else to see. Or maybe you don't want your email provider to allow third parties to mine your email contents for personal data.

Whatever the reason, you need to know how to send secure, encrypted emails—on desktop and mobile services—using some of the most popular email accounts.

1. How to Send a Secure Email In ProtonMail

send encrypted emails using ProtonMail

ProtonMail is a Swiss based email service that prioritizes security and privacy. Not only are your emails secured with zero access end-to-end encryption (which means its contents are safe from the prying eyes of third parties), ProtonMail also protects your anonymity by not keeping IP logs or collecting personal information at sign-up.

There is no need to stress if you're a novice and haven't ventured outside a basic gmail account before—ProtonMail's interface emphasizes simplicity with a modern design.

Related: What Is End-to-End Encryption?

Your data is also protected under an extra layer of legal privacy because ProtonMail's servers are located in Switzerland, therefore their servers are protected by Swiss privacy laws. If that's not enough to put your mind at ease, their physical servers are biometrically secured and distributed across multiple locations.

A basic ProtonMail account is free with paid upgrades available that include extra storage and custom domains. ProtonMail also supports email encryption for your smartphone devices with their iOS and Android apps.

Download: ProtonMail for Android | iOS

2. How to Send a Secure Email In Outlook

microsoft outlook email service

Microsoft's Outlook does not advertise encryption as the centrepiece of its email service, but you'll find it if you know where to look.

Outlook encrypts the connection with the email recipient using Transport Layer Security (TLS). However, this level of encryption is basic and only works when both sender and recipient are using TLS enabled email providers.

Free Outlook users who don't mind getting their hands dirty can use the Mailvelope browser extension to encrypt the contents of their Outlook emails. Mailvelope uses asymmetric encryption and requires users to generate and verify a key to work.

Related: How to Encrypt Your Gmail, Outlook, and Other Webmail

Microsoft 365 supports S/MIME encryption and Microsoft's native message encryption under its Information Rights Management (IRM) feature for its paid subscribers. These options are available through web browser, Microsoft's Mail app, and the Outlook mobile apps.

Microsoft's IRM encryption is easily enabled at send-off by clicking the encryption button built into the email interface. This is a little trickier because it requires setting up an S/MIME certificate in Outlook before the encrypt button becomes available.

Additionally, it requires both the sender and recipient to be using an email service that supports the S/MIME standard.

Outlook's encryption includes the option to prevent forwarding which is especially useful if you want to share confidential data with only a single person. This option also prevents Microsoft Office 365 attachments such as Word or PowerPoint from being opened by recipients other than the person you sent it to.

Download: Outlook for Android | iOS

3. How to Send a Secure Email In Gmail

gmail email service

Like Outlook, encryption is not the focal point for Gmail's email service. However, with a little elbow grease, you can rest easy knowing that your emails are sent securely with an extra layer of encryption.

A free Gmail account supports the most basic TLS encryption. This means your message is encrypted in transit provided the recipients email service is also TLS enabled.

You can also turn on confidential mode from Gmail's email interface which will revoke the recipients ability to copy, print, forward, or download your email and attachments. An expiration date can be set with confidential mode, which can be revoked by the sender at any time.

Gmail users who want to encrypt the contents of their emails can try FlowCrypt, a Chrome and Firefox browser extension that integrates with Gmail.

FlowCrypt uses the PGP encryption standard and requires the recipient to have a PGP system to decrypt the message. FlowCrypt is also available as an Android app and works with any email provider.

For Google Workspace paid account holders, you can enable S/MIME encryption, provided that the recipient is also using an S/MIME enabled email service.

Download: Gmail for Android | iOS

4. How to Send a Secure Email In Mailfence

mailfence encrypted email

Mailfence incorporates Belgian privacy legal protections and encryption in the core of its email service. Mailfence adheres to its motto, "privacy is a right, not a feature" by shielding your data from surveillance and nosy third-parties that want to serve you ads.

Mailfence secures your emails with OpenPGP end-to-end encryption. The email service facilitates ease of use with a browser based interface. Mailfence gives you the freedom to choose which emails you want to encrypt, which means you can use Mailfence without requiring every recipient to decode your sent emails.

Mailfence is free for a basic account with paid upgrades available that include extra inbox space and priority email and telephone support among other benefits.

Mailfence does not have a mobile app; however its webpage is designed to be mobile screen friendly.

5. How to Send a Secure Email In Tutanota

tutanota email service

Tutanota is an open source email service that calls itself the world's most secure.

Tutanota uses end-to-end encryption and optional multi-factor authentication to keep your emails ultra secure. Encryption is a built-in feature meaning all your correspondence are automatically encrypted.

And it goes a step further and encrypts your entire mailbox including contacts and stored emails.

Tutanola is free for a basic account and includes 1 GB of storage, with paid upgrades available depending on your individual needs.

Tutanota can be accessed through your web browser, with apps available for Windows, macOS, Linux, and your iOS or Android device.

Download: Tutanota for Android | iOS

Which Email Service Is Right For You?

Depending on your individual needs and whether you want to pay for an email service, the email services outlined in this article provide strong security with varying benefits depending on what exactly you are after.

If you don't mind doing the hard yards yourself and installing a browser extension, you can send emails securely for free with Outlook and Gmail. ProtonMail, Mailfence, and Tutanota also provide basic account features for free with robust security.