9 Downsides of Proton Mail: What to Know Before Switching from Gmail

Hi, Hoda here!

Proton Mail is a very appealing service if you care about email privacy.

I use Proton Mail as my main email myself and recommend it, but it isn’t a complete upgrade over Gmail or Outlook.

Especially if you’ve used Gmail or Google Workspace for a long time, you may run into moments like:

“Gmail was more convenient for this.”

“I can’t use it the way I expected.”

So this time, I’m going to focus on the downsides of Proton Mail on purpose.

Rather than just listing the bad points, I’ll also explain why each limitation exists, who it actually affects, and whether there’s a workaround.

To give the conclusion first, most of Proton Mail’s downsides are trade-offs for putting privacy first.

So if you understand the downsides below and you think, “I’d rather keep control of my email contents, even if it’s less convenient than Google,” I think Proton Mail is an email service you can confidently consider.

Proton Mail Downsides at a Glance

First, here’s a summary of the main downsides.

Some of these aren’t just “Proton Mail’s fault.” They also include constraints that are hard to avoid with encrypted email.

Let’s look at each one in detail.

Downside 1: Fewer Third-Party Integrations Than Gmail

Personally, I think the first thing to check before switching to Proton Mail is integration with other services.

Gmail and Google Workspace have users all over the world, so you’ll find a

“Connect your Google account”

button in things like:

• CRMs
• Customer management tools
• Automation tools
• Calendar apps
• Sales tools
• AI tools
• Chrome extensions
• Various other SaaS products

Proton Mail doesn’t have an external ecosystem on that scale yet.

In fact, user reviews of Proton Mail for Business also cite fewer integrations with outside services and extensions compared with Google Workspace and Microsoft 365 as a downside.

Of course, Proton has also expanded its own lineup considerably, with:

• Proton Calendar
• Proton Drive
• Proton Pass
• Proton VPN
• Proton Docs
• Proton Sheets
• Proton Meet

So for typical personal use, there are far fewer situations where this causes problems now.

However, if you’re someone who

“works with Google Workspace at the center and connects 20 different SaaS tools to it,”

you should think carefully before moving to Proton as is.

That Said, Integration Within Proton Is Growing

On the other hand, if you’re someone who

“doesn’t want to depend on services other than Google,”

the story is the opposite.

With Proton Mail at the center, you can build an environment of

Mail + Calendar + Drive + Pass + VPN

so the range of things you can do entirely within Proton keeps growing.

In other words, the difference is:

Choose Google for integration with the outside world.

Choose Proton if you want to keep everything with services that share the same privacy philosophy. Proton Drive in particular is more secure than Google Drive, so you can use it for things like sharing files with clients.

Downside 2: Full-Text Search of Message Bodies Isn’t as Simple as in Gmail

If you keep a lot of email, search is probably what you care about most.

Proton Mail’s servers can’t freely read the body of your email.

That’s an advantage for privacy, but a disadvantage for search.

It means Proton can’t simply use the approach Gmail does, where

“Google’s servers search the email bodies and return the results.”

Proton Mail Builds a Search Index on Your Device

To search message bodies in the web version of Proton Mail, you first build a local search index.

Email is downloaded to your device and decrypted, and an encrypted search index is stored on that device.

Once it’s built, you can search message bodies, but it has these characteristics:

• The initial index build can take a while
• Processing can get heavy if you have a lot of email
• You need to build the index in each browser
• If you clear your browser data, you have to rebuild it
• Depending on your browser’s storage capacity, the range you can search may be limited

If you’re used to Gmail’s search, this may feel a little inconvenient.

This Is a Trade-Off with Encryption

Put the other way around,

this approach is necessary precisely because Proton’s servers can’t search your message bodies.

User reviews also commonly list search as a complaint about Proton Mail.

That said, it isn’t true that you can’t search message bodies today. As shown below, if you simply type a keyword, emails containing a word like HodaPress will show up. And of course, if you narrow results by sender or recipient, the email comes up right away.

Be aware that the old claim that “Proton Mail can’t search message bodies” isn’t accurate.

Downside 3: You Need Bridge to Use It in Outlook, Apple Mail, and Others

You also need to be careful if you normally use an email app such as:

• Microsoft Outlook
• Apple Mail
• Mozilla Thunderbird

With a typical email service, you can sometimes connect just by entering IMAP and SMTP details.

With Proton Mail, to maintain encryption, you put a dedicated app called Proton Mail Bridge in between.

The setup looks like this:

Proton Mail ↔ Bridge ↔ Outlook / Apple Mail / Thunderbird

Bridge handles encryption and decryption in your local environment.

Bridge Is Paid-Plan Only

Here’s the downside.

Proton Mail Bridge is available only on paid plans.

Free users basically use Proton’s official environments, such as:

• The web version
• iOS
• Android

Also, Proton Mail Bridge is for Windows, macOS, and Linux, and can’t be used on smartphones.

The Official Desktop App Is Only Free for 14 Days

Proton Mail now also offers official:

• Windows app
• macOS app
• Linux app

However, free accounts can use the desktop app only as a 14-day trial.

If you want to keep using the desktop app, you need a paid plan.

It’s a poor fit if you

“want to keep using a dedicated PC app with free email.”

On the other hand, if you don’t mind reading your email in a browser, the free version works just fine.

Downside 4: The Free Plan Has Some Limits

Proton Mail has a free plan.

The level of encryption is the same as on paid plans, so it’s a very good free email service.

That said, there are feature limits.

As of 2026, the main ones are:

Storage starts at 500 MB, and you can increase it to up to 1 GB by completing the getting-started checklist.

Small Compared with Gmail’s Free 15 GB

Storage is the biggest concern.

With Gmail, you get 15 GB free across your whole Google account.

Proton Mail Free, on the other hand, offers up to 1 GB of email storage.

For message text alone, 1 GB can hold a large amount, but if you often receive attachments such as:

• PDFs
• Photos
• Excel files
• PowerPoint files
• Videos

your storage may fill up quickly. If it’s text only, you usually won’t have a problem.

Paid Plans Ease the Limits Considerably

With Mail Plus, you get things like:

• 15 GB
• Multiple email addresses
• Unlimited folders and labels
• Custom domain
• Bridge
• Auto-forwarding

So rather than treating the free version as a finished free email service, it’s easier to think of it as

a plan for checking how Proton Mail feels to use.

Downside 5: Custom Domains Require a Paid Plan

Some of you will want to use a custom domain email for work, such as:

info@example.com

contact@example.com

You can use custom domains with Proton Mail too.

However, you can’t use them on the free plan.

For individuals, they’re available starting with paid plans:

• Mail Plus: 1 domain
• Proton Unlimited: 3 domains

For companies and teams, Proton Mail for Business plans are also available.

This isn’t an unusual pricing structure unique to Proton, but

you can’t run custom domain email on free Proton Mail,

so keep that in mind.

For sole proprietors and freelancers, Mail Plus with one custom domain is enough in many cases.

Downside 6: Subject Lines Aren’t End-to-End Encrypted

Some people may think that if they use Proton Mail,

everything in the email is end-to-end encrypted.

However, the subject line is not covered by end-to-end encryption.

This isn’t Proton Mail cutting corners on encryption. It’s to maintain compatibility with current email standards such as OpenPGP.

So it’s safer not to put words in the subject line that would themselves reveal confidential information, such as:

“Confidential documents on the acquisition of Company X”

“About Client A’s illness”

“Unreleased pricing for new product X”

Instead, keep it to something like:

“About the document”

“Regarding the other day”

and put the important content in the body.

Proton Doesn’t Freely Access Your Subject Lines Either

The subject line not being E2EE doesn’t mean anyone can see it.

Proton’s policy is not to provide user information to outside parties without a formal Swiss legal order or similar.

Still, you need to understand the difference between

the body, which Proton technically can’t decrypt itself,

and

metadata, which can be provided if there’s a legal process.

Downside 7: Regular Email to Gmail and Other External Recipients Isn’t Automatically E2EE

This is another easily misunderstood point.

Between Proton Mail users,

the body and attachments are automatically end-to-end encrypted.

However, when you send regular email to an outside service, as in

Proton Mail → Gmail

Proton Mail → Outlook

Proton’s E2EE doesn’t extend to the recipient’s side.

TLS encryption is used in transit, but the recipient’s email service may be able to access the body of the email.

If You Want to Send Encrypted Email to External Users

In that case, you can use:

• Password-protected email
• PGP

With password-protected email, you can share content in encrypted form even if the recipient isn’t a Proton Mail user.

In other words,

using Proton Mail doesn’t mean your email with everyone is automatically fully encrypted.

This is something to understand if you use Proton Mail.

Downside 8: Some Web Services May Not Accept Proton Mail Addresses

It’s become quite rare, but

there may be websites where you can’t sign up with a Proton Mail address.

Proton itself addresses this issue in its official support pages.

Possible reasons include:

• A service that doesn’t recognize Proton Mail blocks free email providers across the board
• A service limits which email providers it accepts as an anti-fraud measure
• The domain has been blocked because of past mass sign-ups or similar

Proton says that since Proton Mail is much better known now, this problem has become less common.

There Are Workarounds

If @proton.me doesn’t work, you can:

• Use the paid-plan @pm.me address
• Use a custom domain
• Contact the site
• Report it to Proton support

If you use a custom domain for work, you can mostly ignore this issue.

Still, it’s a downside worth knowing about if you’re

someone who wants to sign up for all kinds of web services with a free @proton.me address.

Downside 9: It Isn’t a Fully Anonymous Email Service

This is very important.

Proton Mail ≠ anonymous email.

What Proton Mail emphasizes is privacy.

That’s a little different from anonymity.

Proton’s general policy is not to permanently store IP addresses tied to accounts, but information such as IP addresses may be handled in connection with:

• Abuse prevention
• Spam prevention
• Cases where the user has enabled authentication logs
• Formal Swiss legal orders

Proton Mail’s transparency report also states that it may comply with disclosure orders that go through formal Swiss legal processes.

However, Proton can’t decrypt the body of encrypted email itself, so even with a legal order, it can’t decrypt the body and hand it over.

“Anonymous” and “Private” Are Different

For example, even if you use Proton Mail, you aren’t fully anonymous if you:

• Write your real name in the body of an email
• Pay with your own credit card
• Use the same information as your usual social media accounts
• Log in from your own IP address

If you truly need anonymity, you’ll need to think about things like:

• A VPN
• Tor
• Running accounts without personal information

Most regular users don’t need to go that far, but

the belief that “using Proton Mail makes you untraceable no matter what you do”

is wrong.

It’s Not Suited to Newsletters or Bulk Email

One more point, which matters depending on your use case.

Proton Mail is not a newsletter sending tool.

The free plan has a sending limit of 150 emails per day.

Paid plans also have sending limits that depend on factors such as account reputation, and the maximum number of recipients per email is 100.

Proton itself says the service isn’t intended for bulk email or spam.

So if your goal is things like:

• Newsletters
• Mass mailings
• Marketing automation
• Newsletters to thousands of people

you’re better off using a dedicated service such as Benchmark Email, Brevo, Mailchimp, or Klaviyo.

Proton Mail is a service for regular email, one-to-one or with a small number of people.

Some Downsides Mentioned in Older Articles Have Been Fixed

Proton Mail has added a lot of features over the past few years.

So if you’re reading forum posts or comparison articles from a few years ago, pay attention to the dates.

“You Can’t Auto-Forward from Proton Mail” Is Outdated

On paid plans, you can now automatically forward email that arrives in Proton Mail to an external address.

You can also set conditions, such as

“only forward email from this sender.”

“It’s Hard to Migrate from Gmail” Has Also Improved a Lot

Now there are Easy Switch and the Gmail connection, which let you:

• Import your Gmail email
• Send new Gmail email to Proton
• Send from Proton Mail using your Gmail address

You don’t have to abandon Gmail all at once.

“You Can’t Search Message Bodies” Is No Longer Accurate Either

With the local index approach explained earlier, you can search encrypted message bodies in the web version.

It isn’t as simple as Gmail, but

it isn’t true that you can’t search message bodies at all.

If you judge by articles from a few years ago, Proton Mail will look less convenient than it is today, so be careful.

Is There Still a Benefit to Using Proton Mail?

After reading this far, you may be thinking,

“There are more downsides than I expected.”

Even so, I think Proton Mail is still well worth recommending.

That’s because most of the downsides I’ve covered here are the flip side of a design that

“keeps the email provider from freely processing your email bodies.”

Proton Mail offers:

• Zero-access encryption for stored email
• End-to-end encryption between Proton users
• No ads
• Email tracker blocking
• Open-source apps
• Operation based in Switzerland
• Hide-my-email aliases
• Password-protected email
• Integration with Proton Pass, VPN, Drive, and more

It helps to think of it this way: Proton isn’t trying to build email that’s more convenient than Gmail.

It’s building email with different priorities from Gmail.

Who Won’t Mind the Downsides of Proton Mail

If you fit the following, I think the downsides covered here won’t be a big problem:

• You mainly use email through the official web and mobile apps
• You don’t need as many third-party integrations as Gmail offers
• You don’t run full-text searches on old email every day
• You’d put privacy slightly ahead of convenience
• You don’t want your email data used for advertising
• You want to run custom domain email securely
• You also want to use Proton VPN and Proton Pass

In particular, if you’re someone who thinks,

“For email, being able to send, receive, search, and sort into folders in the usual way is enough,”

you’ll probably have little trouble moving to Proton Mail.

Who Might Not Want Proton Mail

On the other hand, if you fit the following, you may find it more convenient to keep using Gmail or Google Workspace:

• Your company’s work is built around Google Workspace
• You use a large number of Google account integrations
• You frequently use Gmail’s powerful search
• You want large-capacity email that’s completely free
• You want to use Outlook or Apple Mail while staying on a free plan
• You want to send newsletters in bulk
• You’re looking for “completely anonymous email”

I don’t think you need to force a move to Proton Mail for these use cases.

You Don’t Have to Switch Completely from Gmail Right Away

Even if you’re interested in Proton Mail, many people probably feel, “It’s scary to give up the Gmail I’ve used for over 10 years.”

In that case, you don’t need to switch completely all at once.

Here’s what I’d recommend:

1. Create a Proton Mail Free account
2. Gradually move your everyday email to Proton
3. Set up the Gmail connection or Easy Switch
4. Use it for a few weeks to a few months
5. If there are no problems, consider Mail Plus or Proton Unlimited

Since Proton Mail has a free plan, there’s little risk of ending up thinking “I subscribed and it didn’t suit me.” And in the first place, you can never have too many secondary email addresses, so keeping Gmail as your main and managing Proton Mail as a secondary address is perfectly fine too.

Frequently Asked Questions About Proton Mail’s Downsides

Is Proton Mail hard to use?

It has the usual features, including sending and receiving, folders, labels, filters, scheduled send, and snooze, so it isn’t especially hard to use for general email.

That said, compared with Gmail, you may find integrations with outside services and full-text search less convenient.

Can’t Proton Mail search message bodies?

It can now.

In the web version, you can search message bodies by creating an encrypted search index on your device.

However, it isn’t a system where the server instantly searches everything as Gmail does, so the initial index build and similar steps can take time.

Can I use Proton Mail in Outlook or Apple Mail?

Yes.

However, you need Proton Mail Bridge.

Bridge is a feature for paid Proton Mail plans.

Is the free version of Proton Mail enough?

If you only use email lightly for personal use, the free version is enough to try it out.

On the other hand, a paid plan is better suited if you want to:

• Increase your storage
• Use a custom domain
• Use Bridge
• Create many folders
• Set up auto-forwarding

Are Proton Mail subject lines encrypted?

Subject lines aren’t end-to-end encrypted.

This is to maintain compatibility with email standards.

I recommend putting confidential information in the body, not the subject line.

Is email sent to Gmail end-to-end encrypted?

If you send to Gmail or other external email services in the usual way, it won’t be automatically E2EE.

If you want to send with E2EE to external users, you can use Proton Mail’s password-protected email or PGP.

Is Proton Mail completely anonymous?

It isn’t a service that guarantees complete anonymity.

Proton Mail is an email service that emphasizes privacy.

If you need anonymity, you’ll need to combine it with other measures such as a VPN or Tor.

Isn’t Proton Mail a suspicious service?

Proton is a Swiss company that has provided its services since 2014, and it publishes its apps’ source code and undergoes third-party audits.

That said, with any cloud service you can’t use it without trusting the operating company at all.

With Proton Mail, the design that even Proton can’t decrypt your email bodies keeps the scope of that trust as small as possible.

Can I use Proton Mail in my own language?

Yes. Proton Mail supports multiple interface languages, and you can pick yours in the language settings. You can use it in your language without awkward translations.

Summary: Proton Mail’s Downsides Are Mostly “Trade-Offs for Privacy”

Proton Mail does have downsides.

In particular, you should understand these before subscribing:

• Fewer third-party integrations than Gmail
• Full-text search takes extra effort
• Bridge and custom domains are paid
• The free version has limits on storage and features
• Subject lines aren’t E2EE
• Email to external recipients isn’t automatically E2EE

Personally, though, I don’t think any of these is a reason not to recommend Proton Mail.

Rather, Proton Mail’s philosophy is to give up a little of

“the convenience of an email provider being able to freely process your content”

in order to

“keep your email as much your own as possible.”

If you need the convenience of Gmail or Google Workspace, there’s no need to force a switch.

On the other hand, if you’re someone who wants to

put more weight on email privacy than you do now,

I think Proton Mail is worth choosing even after you understand a few constraints.

Fortunately, there’s a free plan for personal use.

I recommend first trying Proton Mail while keeping your usual Gmail, and moving over for real once you feel, “These differences are no problem.”