{"id":112333,"date":"2026-11-02T15:08:27","date_gmt":"2026-11-02T15:08:27","guid":{"rendered":"https:\/\/mailrelay.com\/glossary\/protonmail\/"},"modified":"2026-11-03T21:03:08","modified_gmt":"2026-11-03T21:03:08","slug":"protonmail","status":"publish","type":"glossary","link":"https:\/\/mailrelay.com\/en\/glossary\/protonmail\/","title":{"rendered":"Proton Mail"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Proton Mail is an encrypted email service from the Swiss company Proton: a @proton.me address whose messages not even the company itself can read.<\/p>\n\n<p class=\"wp-block-paragraph\">Here&#8217;s how its encryption works, what the free account includes, how to use it in other email clients and what its limits are.<\/p>\n\n<h2 class=\"wp-block-heading\">What is Proton Mail?<\/h2>\n\n<p class=\"wp-block-paragraph\">It&#8217;s an <a href=\"https:\/\/mailrelay.com\/en\/glossary\/email-service\/\" target=\"_blank\" rel=\"noopener\">email service<\/a> built for privacy. It was created in 2014 by a team of scientists who met at CERN, and today it is run by Proton AG from Geneva.<\/p>\n\n<p class=\"wp-block-paragraph\">Until 2022 it was written ProtonMail, as one word. Addresses can end in @proton.me or @protonmail.com, and both work the same way.<\/p>\n\n<p class=\"wp-block-paragraph\">Proton also offers a VPN, cloud storage, a password manager and a calendar. In February 2026 it announced more than 100 million users across all its services.<\/p>\n\n<h2 class=\"wp-block-heading\">How does its encryption work?<\/h2>\n\n<p class=\"wp-block-paragraph\">The difference from <a href=\"https:\/\/mailrelay.com\/en\/glossary\/gmail-email\/\" target=\"_blank\" rel=\"noopener\">Gmail<\/a> or <a href=\"https:\/\/mailrelay.com\/en\/glossary\/outlook\/\" target=\"_blank\" rel=\"noopener\">Outlook<\/a> lies in who can read your messages.<\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>Between Proton users<\/strong>, encryption is end-to-end: only the sender and the recipient can see the content.<\/li>\n\n\n\n<li><strong>Your stored messages<\/strong> use zero-access encryption: Proton stores them but can&#8217;t open them.<\/li>\n\n\n\n<li><strong>If you write to another provider<\/strong>, the message goes out as a regular <a href=\"https:\/\/mailrelay.com\/en\/glossary\/email\/\" target=\"_blank\" rel=\"noopener\">email<\/a>, unless you protect it with a password.<\/li>\n<\/ul>\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"577\" src=\"https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-como-funciona-cifrado-1024x577.png\" alt=\"How Proton Mail encryption works: end-to-end between Proton users, zero-access encryption for stored messages and regular email to other providers unless you protect it with a password\" class=\"wp-image-112087\" srcset=\"https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-como-funciona-cifrado-1024x577.png 1024w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-como-funciona-cifrado-300x169.png 300w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-como-funciona-cifrado-768x432.png 768w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-como-funciona-cifrado-1536x865.png 1536w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-como-funciona-cifrado-110x62.png 110w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-como-funciona-cifrado-60x34.png 60w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-como-funciona-cifrado.png 1671w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n<p class=\"wp-block-paragraph\">One thing isn&#8217;t end-to-end encrypted: the subject line, the sender and the recipient, which are needed to deliver the email.<\/p>\n\n<div class=\"wp-block-group has-very-light-gray-background-color has-background\" style=\"border-radius:8px;padding-top:24px;padding-right:28px;padding-bottom:24px;padding-left:28px\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>Do you send your newsletter from Proton Mail?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">With 150 messages a day, you can&#8217;t reach your whole list. With Mailrelay you send to all your subscribers, with statistics and automatic unsubscribes. Free account with up to 80,000 emails a month.<\/p>\n\n\n\n<div class=\"wp-block-buttons is-layout-flex wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button is-style-mailrelay-primary-button\"><a class=\"wp-block-button__link wp-element-button\" href=\"https:\/\/mailrelay.com\/en\/signup\/?utm_medium=cta&#038;utm_campaign=protonmail\">Create a free account<\/a><\/div>\n<\/div>\n<\/div><\/div>\n\n<h2 class=\"wp-block-heading\">What does the free account include?<\/h2>\n\n<p class=\"wp-block-paragraph\">The free account works well for light personal use, but it has clear limits:<\/p>\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Feature<\/th><th>Free account<\/th><\/tr><\/thead><tbody><tr><td>Email storage<\/td><td>500 MB, expandable to 1 GB<\/td><\/tr><tr><td>Addresses<\/td><td>1 (@proton.me)<\/td><\/tr><tr><td>Messages sent<\/td><td>150 a day<\/td><\/tr><tr><td>Folders and labels<\/td><td>3 of each<\/td><\/tr><tr><td><a href=\"https:\/\/mailrelay.com\/en\/glossary\/attachment\/\" target=\"_blank\" rel=\"noopener\">Attachments<\/a><\/td><td>Up to 25 MB<\/td><\/tr><tr><td>Custom domain<\/td><td>No<\/td><\/tr><tr><td>Use in Outlook or <a href=\"https:\/\/mailrelay.com\/en\/glossary\/thunderbird\/\" target=\"_blank\" rel=\"noopener\">Thunderbird<\/a><\/td><td>No (requires a paid plan)<\/td><\/tr><\/tbody><\/table><\/figure>\n\n<p class=\"wp-block-paragraph\">Watch out for inactivity. A free account you don&#8217;t use for 12 months may be deleted, along with all its content. Proton warns you first, but it&#8217;s worth logging in from time to time.<\/p>\n\n<h2 class=\"wp-block-heading\">What paid plans are there?<\/h2>\n\n<p class=\"wp-block-paragraph\">Paid plans remove the daily limit and add storage, more addresses and a custom domain.<\/p>\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Plan<\/th><th>Who it&#8217;s for<\/th><th>Highlights<\/th><\/tr><\/thead><tbody><tr><td>Mail Plus<\/td><td>Personal use<\/td><td>15 GB, 10 addresses and 1 custom domain<\/td><\/tr><tr><td>Proton Unlimited<\/td><td>Personal use with all services<\/td><td>500 GB, 15 addresses and 3 domains<\/td><\/tr><tr><td>Duo and Family<\/td><td>Couples and families<\/td><td>Several accounts with shared storage<\/td><\/tr><tr><td>Business plans<\/td><td>Teams<\/td><td>Email on your domain, plus admin tools<\/td><\/tr><\/tbody><\/table><\/figure>\n\n<p class=\"wp-block-paragraph\">Prices vary by billing period and currency: check them on Proton&#8217;s website. With a business plan, it works as an encrypted <a href=\"https:\/\/mailrelay.com\/en\/glossary\/corporate-email\/\" target=\"_blank\" rel=\"noopener\">corporate email<\/a>.<\/p>\n\n<h2 class=\"wp-block-heading\">How do you use Proton Mail in Outlook or Thunderbird?<\/h2>\n\n<p class=\"wp-block-paragraph\">The service doesn&#8217;t support POP3 or direct <a href=\"https:\/\/mailrelay.com\/en\/glossary\/imap\/\" target=\"_blank\" rel=\"noopener\">IMAP<\/a> and <a href=\"https:\/\/mailrelay.com\/en\/glossary\/smtp\/\" target=\"_blank\" rel=\"noopener\">SMTP<\/a> access, because its servers can&#8217;t read your messages. To use it in an <a href=\"https:\/\/mailrelay.com\/en\/blog\/2026\/04\/03\/email-clients\/\" target=\"_blank\" rel=\"noopener\">email client<\/a> you need <strong>Proton Mail Bridge<\/strong>, an app for Windows, Mac and Linux included in the paid plans.<\/p>\n\n<p class=\"wp-block-paragraph\">Bridge encrypts and decrypts on your computer and creates a local server:<\/p>\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Setting<\/th><th>Incoming (IMAP)<\/th><th>Outgoing (SMTP)<\/th><\/tr><\/thead><tbody><tr><td>Server<\/td><td>127.0.0.1<\/td><td>127.0.0.1<\/td><\/tr><tr><td>Port (default)<\/td><td>1143<\/td><td>1025<\/td><\/tr><tr><td>Encryption<\/td><td>STARTTLS<\/td><td>STARTTLS<\/td><\/tr><tr><td>Password<\/td><td>The one Bridge generates<\/td><td>The same one<\/td><\/tr><\/tbody><\/table><\/figure>\n\n<p class=\"wp-block-paragraph\">Don&#8217;t use your Proton account password: Bridge creates a different one for each client.<\/p>\n\n<h2 class=\"wp-block-heading\">Proton Mail, Gmail or Outlook?<\/h2>\n\n<p class=\"wp-block-paragraph\">It depends on what matters more to you: privacy or convenience.<\/p>\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>If\u2026<\/th><th>Go for<\/th><\/tr><\/thead><tbody><tr><td>Privacy comes first<\/td><td>Proton Mail<\/td><\/tr><tr><td>You want 15 GB free and lots of integrations<\/td><td>Gmail or Outlook<\/td><\/tr><tr><td>You use an iPhone, iPad and Mac<\/td><td><a href=\"https:\/\/mailrelay.com\/en\/glossary\/icloud-mail\/\" target=\"_blank\" rel=\"noopener\">iCloud Mail<\/a><\/td><\/tr><tr><td>You need email for your business<\/td><td>Proton for Business, <a href=\"https:\/\/mailrelay.com\/en\/glossary\/google-workspace\/\" target=\"_blank\" rel=\"noopener\">Google Workspace<\/a> or <a href=\"https:\/\/mailrelay.com\/en\/glossary\/microsoft-365\/\" target=\"_blank\" rel=\"noopener\">Microsoft 365<\/a><\/td><\/tr><tr><td>You just want to sign up on a website without giving out your address<\/td><td>An alias or a <a href=\"https:\/\/mailrelay.com\/en\/glossary\/temporary-email\/\" target=\"_blank\" rel=\"noopener\">temporary email<\/a><\/td><\/tr><\/tbody><\/table><\/figure>\n\n<h2 class=\"wp-block-heading\">Can you use Proton Mail to send newsletters?<\/h2>\n\n<p class=\"wp-block-paragraph\">It&#8217;s not a good idea. The free account is capped at 150 messages a day, and the paid plans are designed for personal and business email, not for sending to an entire list.<\/p>\n\n<p class=\"wp-block-paragraph\">You also don&#8217;t get open and click statistics or unsubscribe management. And, by design, Proton doesn&#8217;t track what happens to your messages, which is exactly what a campaign needs to measure.<\/p>\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-vs-herramienta-email-marketing-1024x576.png\" alt=\"Sending newsletters: Proton Mail versus an email marketing tool, with 150 messages a day and no statistics versus sending to your whole list with opens, clicks and automatic unsubscribes\" class=\"wp-image-112091\" srcset=\"https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-vs-herramienta-email-marketing-1024x576.png 1024w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-vs-herramienta-email-marketing-300x169.png 300w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-vs-herramienta-email-marketing-768x432.png 768w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-vs-herramienta-email-marketing-1536x864.png 1536w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-vs-herramienta-email-marketing-110x62.png 110w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-vs-herramienta-email-marketing-60x34.png 60w, https:\/\/mailrelay.com\/wp-content\/uploads\/2026\/11\/protonmail-vs-herramienta-email-marketing.png 1672w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n<p class=\"wp-block-paragraph\">That&#8217;s what <a href=\"https:\/\/mailrelay.com\/en\/blog\/2022\/11\/08\/how-to-send-a-newsletter-a-step-by-step-guide\/\" target=\"_blank\" rel=\"noopener\">bulk email<\/a> tools are for, and they respect each provider&#8217;s <a href=\"https:\/\/mailrelay.com\/en\/glossary\/sending-limits\/\" target=\"_blank\" rel=\"noopener\">sending limits<\/a>. And if your subscribers use Proton, they&#8217;ll receive your newsletters like any other email.<\/p>\n\n<h2 class=\"wp-block-heading\">How Mailrelay helps you<\/h2>\n\n<p class=\"wp-block-paragraph\">With Mailrelay you send your newsletters to your whole list from your own address and an <a href=\"https:\/\/mailrelay.com\/en\/glossary\/email-authentication\/\" target=\"_blank\" rel=\"noopener\">authenticated<\/a> <a href=\"https:\/\/mailrelay.com\/en\/glossary\/sending-domain\/\" target=\"_blank\" rel=\"noopener\">sending domain<\/a>, without the daily cap of a personal email account.<\/p>\n\n<p class=\"wp-block-paragraph\">The <a href=\"https:\/\/mailrelay.com\/en\/glossary\/free-mailing\/\" target=\"_blank\" rel=\"noopener\">free account<\/a> includes up to 80,000 emails a month and 20,000 contacts.<\/p>\n\n<p class=\"wp-block-paragraph\">You get a visual editor, automations, open and click statistics, and automatic management of unsubscribes and bounces, with human support on every plan. All the details are on the <a href=\"https:\/\/mailrelay.com\/en\/pricing\/\" target=\"_blank\" rel=\"noopener\">pricing<\/a> page.<\/p>\n\n<div class=\"wp-block-group has-very-light-gray-background-color has-background\" style=\"border-radius:8px;padding-top:24px;padding-right:28px;padding-bottom:24px;padding-left:28px\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>Your private email, your newsletters with Mailrelay<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Templates, automations and statistics, with human support on every plan.<\/p>\n\n\n\n<div class=\"wp-block-buttons is-layout-flex wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button is-style-mailrelay-primary-button\"><a class=\"wp-block-button__link wp-element-button\" href=\"https:\/\/mailrelay.com\/en\/signup\/?utm_medium=cta&#038;utm_campaign=protonmail\">Try Mailrelay for free<\/a><\/div>\n<\/div>\n<\/div><\/div>\n\n<h2 class=\"wp-block-heading\">Frequently asked questions about Proton Mail<\/h2>\n\n<p class=\"wp-block-paragraph\">These are the most common questions.<\/p>\n\n<h3 class=\"wp-block-heading\">Is Proton Mail free?<\/h3>\n\n<p class=\"wp-block-paragraph\">Yes. It has a free account with 1 GB of storage and 150 messages a day. Paid plans add storage, addresses and a custom domain.<\/p>\n\n<h3 class=\"wp-block-heading\">Are Proton Mail and ProtonMail the same thing?<\/h3>\n\n<p class=\"wp-block-paragraph\">Yes. In 2022 the company started writing it as two words, Proton Mail, when it brought all its services together under the Proton brand.<\/p>\n\n<h3 class=\"wp-block-heading\">Is Proton Mail secure?<\/h3>\n\n<p class=\"wp-block-paragraph\">It&#8217;s one of the most private email services: it encrypts your stored messages and the ones you send to other Proton users. Even so, protect your account with two-step verification and watch out for <a href=\"https:\/\/mailrelay.com\/en\/glossary\/phishing\/\" target=\"_blank\" rel=\"noopener\">phishing<\/a>, as with any other email service.<\/p>\n\n<h3 class=\"wp-block-heading\">Can I use my own domain?<\/h3>\n\n<p class=\"wp-block-paragraph\">Yes, with a paid plan. Mail Plus includes one custom domain, and the business plans include several.<\/p>\n\n<h3 class=\"wp-block-heading\">Why can&#8217;t I set up Proton Mail in Outlook?<\/h3>\n\n<p class=\"wp-block-paragraph\">Because you need Proton Mail Bridge, which is only available on paid plans. With the free account, use the website or the official app.<\/p>\n\n<h2 class=\"wp-block-heading\">Related posts<\/h2>\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/mailrelay.com\/en\/glossary\/gmail-email\/\">Gmail<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/mailrelay.com\/en\/glossary\/outlook\/\">Outlook<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/mailrelay.com\/en\/glossary\/icloud-mail\/\">iCloud Mail<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/mailrelay.com\/en\/glossary\/yahoo-mail\/\">Yahoo Mail<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/mailrelay.com\/en\/glossary\/google-workspace\/\">Google Workspace<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/mailrelay.com\/en\/glossary\/microsoft-365\/\">Microsoft 365<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/mailrelay.com\/en\/glossary\/corporate-email\/\">Corporate email<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/mailrelay.com\/en\/glossary\/imap\/\">IMAP<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/mailrelay.com\/en\/glossary\/temporary-email\/\">Temporary email<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/mailrelay.com\/en\/glossary\/phishing\/\">Phishing<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/mailrelay.com\/en\/glossary\/thunderbird\/\">Thunderbird<\/a><\/li>\n<\/ul>\n","protected":false},"template":"","class_list":["post-112333","glossary","type-glossary","status-publish","hentry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.7 - 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