Yes. You can verify any @Protonmail.com address in real time with a direct SMTP handshake that provides 99.7% accuracy. Protonmail.com is operated by Proton AG, runs 2 mail servers, enforces 2 of 3 authentication standards, and is currently responding to SMTP.
Every check returns one of three clear outcomes so you know exactly what to do with the address.
The mailbox exists and accepts mail. Send with confidence, the address is deliverable.
The mailbox does not exist, is disposable, or will hard-bounce. Remove it to protect your sender reputation.
The server is catch-all or greylisting, so existence cannot be confirmed. Send selectively and watch engagement.
protonmail.com publishes 2 MX records. The primary mail exchanger is mail.protonmail.ch, hosted by protonmail.ch, and it is currently reachable and answering SMTP. Mail is routed through these servers in priority order, lowest number first.
| Priority | Hostname | IP | Status |
|---|---|---|---|
| 5 | mail.protonmail.ch | 176.119.200.128 | Reachable |
| 10 | mailsec.protonmail.ch | 185.70.42.129 | Reachable |
220-mailinosl105.protonmail.ch ESMTP PostfixYes. protonmail.com is a valid email provider, operated by Proton AG. Addresses are persistent and real mail reaches a genuine recipient. Individual mailboxes still go stale, so verify each one before you send.
A live SMTP handshake connects to Protonmail.com's mail server and asks whether the mailbox exists using the RCPT TO command, without ever transmitting a message. The recipient never sees the check.
Each address runs through 30+ checks including SMTP existence, catch-all detection, role-account filtering, and disposable matching. The same engine has verified billions of addresses since 2012.
Every unverified address is a gamble. Here is what happens when you skip verification and mail a list that has not been cleaned.
Free inboxes get abandoned constantly. Verification drops the dead protonmail.com mailboxes before you mail them.
Mistyped protonmail.com addresses fail a real SMTP check, so they never turn into a hard bounce.
A clean list keeps your bounce rate low, and a low bounce rate is what protects inbox placement on a big send.
Mailing only live protonmail.com addresses raises every rate that matters: opens, clicks, and replies.
Protonmail.com is Proton AG, registered through MarkMonitor, Inc. and first seen Aug 21, 2010.
ProtonMail is a privacy-focused free email service founded in 2013 by scientists from CERN, headquartered in Geneva, Switzerland. Operated by Proton AG, ProtonMail distinguishes itself with end-to-end encryption, zero-access architecture, and strong privacy protections under Swiss law. ProtonMail's MX records point to mail.protonmail.ch and mailsec.protonmail.ch, hosted in secure data centers in Switzerland.
Email verification of ProtonMail addresses has specific characteristics tied to the service's privacy-first design. ProtonMail does not operate as a catch-all domain, and SMTP verification returns definitive responses for valid and invalid addresses. However, ProtonMail applies rate limiting to protect against enumeration attacks, so verification tools should use moderate connection rates. ProtonMail supports plus-addressing (user+tag@protonmail.com), similar to Gmail, which allows users to create aliases that route to their primary inbox.
ProtonMail implements strong email authentication. SPF records authorize Proton's mail servers, DKIM signing is applied to outgoing messages, and a DMARC policy is published. Given ProtonMail's focus on security, their authentication configuration is typically well-maintained and serves as a good reference for proper email authentication setup. ProtonMail also supports custom domains for paid accounts through the Proton Mail Professional and Visionary plans.
For email marketers, ProtonMail users tend to be privacy-conscious individuals who are more likely to scrutinize marketing communications. ProtonMail's spam filtering is less aggressive than major providers like Gmail or Outlook, relying more on SpamAssassin-style scoring. However, ProtonMail users are more likely to manually mark unwanted emails as spam. Best practice is to ensure robust opt-in consent and provide clear unsubscribe mechanisms when emailing ProtonMail addresses. The privacy-focused user base makes transparent data practices especially important.
Upload a CSV or TXT list of Protonmail.com addresses to the bulk email verifier. Every address runs through a live SMTP handshake plus catch-all, role-account and disposable detection, and you download a clean list when processing completes. For real-time checks at signup, use the real-time email verification API.
CSV or TXT with one email per line. No formatting needed.
Each Protonmail.com address is checked with a live server handshake.
Get a verified list with status codes, risk flags, and catch-all detection.
Pay as you go. No subscriptions, and credits never expire.
Everything about verifying email at this domain.
Yes, protonmail.com is a valid and active email domain operated by Proton AG in Switzerland. It is a privacy-focused email service with end-to-end encryption, founded in 2013 by CERN scientists.
No, protonmail.com is not a disposable or temporary email provider. It is a permanent, privacy-focused email service. ProtonMail does support plus-addressing for creating aliases, but these route to permanent accounts.
ProtonMail uses its own mail infrastructure hosted in Switzerland. MX records point to mail.protonmail.ch and mailsec.protonmail.ch, hosted in secure Swiss data centers.
Yes, you can send marketing emails to ProtonMail addresses with proper consent. ProtonMail users tend to be privacy-conscious, so ensure transparent opt-in practices and clear unsubscribe options. Spam filtering uses scoring-based detection.
ProtonMail addresses can be verified via SMTP checks, as the service returns definitive accept/reject responses. Rate limiting is applied to prevent enumeration attacks, so use moderate connection rates. Plus-addressing is supported.
Upload a CSV or TXT list to the bulk email verifier. Every address runs through 30+ checks including SMTP existence, catch-all detection, role-account, and disposable matching. Processing time depends on list size.
99.7% accurate using a direct SMTP handshake with protonmail.com's mail servers, the same engine that has verified billions of addresses since 2012.
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