Their Proton custom domain was blocked when emailing a US state agency until the contact asked admins to unblock.
79signal
295reviewsi
A score out of 100. Negative and mixed reviews take points off, and so does having only a few reviews, so a handful of glowing reviews can’t beat a product many people like.
54% Positive13%33% Negative
Most customers find it reliable for email with a custom domain, an easy switch from Gmail or Google Workspace, and good spam filtering.
What customers love, and what they don’tWhat customers noticed
Customer reviews (295)
Add your reviewShowing 29 reviews mentioning good deliverability Show all
Some providers flag Proton Mail as spam more often than the old Microsoft address, a trade-off they accept.
Used Proton as secondary but emails were marked as spam and they moved away, also hitting Drive and Pass issues.
Uses Proton as the primary provider with a custom domain and has had no deliverability or registration issues.
Some services reject mail from Proton domains, including X support rejecting theirs three times.
Paid Proton user was blocked from buying Ticketmaster tickets for a week because the Proton domain is blacklisted.
Finds Proton spam filtering not quite Google-level but very good, with spam slipping through maybe once per three months.
Proton email is blocked at the college where they work, so student applications never get a response.
Custom domain hosted on Proton landed in spam or was blocked; after switching to iCloud there were no issues.
A county court silently blocked mail from their custom domain, nearly costing a licence until they resent from a protonmail.com address.
Paid Unlimited user since 2020 with a spam filter that works great and not a single issue in six years.
Three years on Proton Unlimited with only one sent email flagged and never received.
Mail from a Proton pm.me address to a Google Workspace university address and to Gmail landed in spam.
Runs a custom domain on Proton for a website and primary mail with few issues and no spam yet.
Transitioned from Gmail to Proton with a custom domain last year and is happy, with no gripes on deliverability.
Their Proton address and domains get flagged on job applications, so they keep Gmail for them.
Proton Plus spam filter flags legitimate emails as spam even after being marked not spam, forcing constant spam-folder checks.
Over a year on Proton using built-in SimpleLogin aliases and has had zero spam emails.
Enjoys Proton as primary email, noting it cut down spam and that paying is needed to benefit from aliases.
Zero issues and a spam filter that is so good.
Finds it harder to use Proton because corporate firewalls block its VPN and mail.
Has never had a site refuse their ProtonMail address.
Uses a pm.me address and has never had issues.
Custom domain through Proton gives no issues with mail from financial institutions or anything else.
Their kids' schools blocked the free Proton domain, so they can receive mail but must reply from Gmail.
Proton mail was only flagged a few times, far fewer than at mailbox.org where it was flagged constantly.
Proton is a reliable company and they have never had rejected or misclassified emails.
Business domain on Proton works fantastic with no blocking experienced yet.
Mostly uses pm.me at Proton and has never had an issue.
Common questions about Proton Mail
What do customers say about Proton Mail?
Most customers find it reliable for email with a custom domain, an easy switch from Gmail or Google Workspace, and good spam filtering. Complaints include weak body-text search, occasional outages, slow support and development, and constant prompts to upgrade. A few report mail from Proton addresses landing in spam.
Is Proton Mail worth it?
Of the 249 reviews with a clear verdict, 54% are positive, 12% mixed and 33% negative. The praise mentioned most is reliable. The most common complaint is poor support.
What do people like about Proton Mail?
The praise reviewers mention most: reliable (47 reviews), easy migration (36 reviews) and good deliverability (24 reviews). For example: Left Proton for Microsoft after two years and called it a mistake, returning in 2025 with their custom domain.
What are the most common complaints about Proton Mail?
The complaints reviewers mention most: poor support (20 reviews), outages (14 reviews) and upsells (8 reviews). For example: Account created via temp email was locked for suspicious activity on first use until another email was added.
What does the signal score of 79 mean?
It's how well reviewed Proton Mail is, out of 100. Negative and mixed reviews take points off, and so does having only a few reviews: a service needs plenty of them, compared with the most-reviewed services here, to reach the high 80s and 90s. It's worked out from reviews only, needs at least 5 of them, and updates as new ones come in.
What are the specs of Proton Mail?
Category: Email hosting. Free plan: Yes.
How does Proton Mail rank?
#2 in Best Email Hosting 2026, ranked by real customer reviews.
Where do these Proton Mail reviews come from?
295 are quotes from Reddit and YouTube, each linked to the original. Customer reviews are checked for spam before they appear. Every review, written here or quoted, is read as positive, mixed or negative.