GMX Mail: Features, Storage, Plans and Limits

GMX Mail is the webmail service of 1&1 Mail & Media GmbH. It is free to use on two main sites: www.gmx.com for English and www.gmx.net for German. The sites print different numbers for storage and attachments, so this guide treats them separately.

Here you will find the features, size limits, paid plans, apps, filters and the limits that catch people out. A table near the end sets GMX beside other free email providers. All GMX facts come from GMX's own websites, read in October 2026. We are not affiliated with GMX. BillionVerify is an email verification service. For a short definition of the provider, read what GMX is in our glossary. To get into a mailbox, follow our sign-in and sign-up guide.

Key facts (checked October 2026):

• GMX's Mail page for English-language accounts lists 65 GB of storage and 50 MB attachments.
• FreeMail comes with 1 GB and 20 MB attachments, per GMX's plan comparison.
• GMX ProMail costs €3.99 monthly and TopMail costs €6.49 monthly on gmx.net, after a free first month.
• GMX's alias article notes that an existing GMX address cannot be changed, and a deleted address stays blocked for at least a year.
• GMX's Help Center states that its filters compare each message with lists of servers known for junk.
• BillionVerify does not charge for unknown results.

What GMX Mail Includes

A mailbox bundles email with tools you would otherwise add yourself. The list draws on GMX's product pages and help pages.

Screenshot: the English product page for GMX Mail.

Mailbox Tools

• Folders and filter rules. You can build folders and rules that sort email by sender or subject. Templates cover common jobs, such as forwarding one sender to another account.
• Alias addresses. One mailbox can hold up to 10 sender email addresses. Aliases may use other GMX endings, such as gmx.us, gmx.co.uk or gmx.ca.
• Mail Collector. It pulls email from outside providers into your inbox. Up to 10 accounts fit.
• Contacts and Organizer. An address book and an online calendar sit in the same login.
• Search. One search bar scans email, files, appointments and contacts.

Cloud and Online Office

The cloud comes with every login. The gmx.com domain lists 2 GB of free cloud room, and gmx.net lists 4 GB. Files can be shared with a link.

Online Office opens Word, Excel and PowerPoint files in the browser. Attachments of those types open there too.

Features Listed Only on gmx.net

That site names two extras. The first is the Intelligentes Postfach, an inbox that sorts email into overviews for orders, social media, newsletters and contracts. You can switch it off at any time. The second is the E-Mail-Siegel, a seal that marks email from checked companies.

GMX Mail Storage and Attachment Limits

GMX gives two sets of numbers because the domains sell different products. No page explains the gap. Read the row for the domain you use.

Sources: GMX's Mail, Storage and Cloud pages on gmx.com, plus the tariff table on gmx.net.

Check How Much Room Is Left

Open Email Settings, then Folder Overview. The view shows the space used and the item count of each folder. A full mailbox bounces new email, so begin there.

GMX suggests three ways to free room:

1. Empty a folder from the wrench icon next to it.
2. Route unwanted senders to Spam or Trash with a filter rule.
3. Cut the time that Trash keeps items from unlimited to 30 days.

Every folder keeps items without a time limit, except Spam. It holds junk for 30 days at most, then deletes it for good.

When an Attachment Is Too Big

A file over the limit will not attach. GMX points to the cloud. Upload the file, press Share and paste the link into your email. You can set an end date, decide whether guests may edit, and add a PIN.

GMX's attachment page gives a second reason to use links. A recipient with little room may never receive a bulky attachment. Then a notice from mailer-daemon reaches you.

GMX Free Email and the Paid Plans

A GMX free email account costs nothing on either domain. Paid upgrades, ProMail and then TopMail, exist only on gmx.net. Our check of the English site found no paid tier.

Screenshot: GMX's German tariff table, one column per plan.

What Each Plan Adds

The standard endings are @gmx.net, @gmx.de, @gmx.at, @gmx.ch and @mein.gmx. GMX names @gmx.com and @gmx.org among the premium endings. So a gmx.net customer can pay for a gmx.com address.

The GMX free plan has one more limit. Help comes from a chat for simple topics and a contact form.

Terms for GMX ProMail

One month costs nothing. After that the monthly price is collected half-yearly in advance. The contract runs 13 months, test month included. Cancel any time during the test. To end a ProMail test early, open Mein Account in your mailbox. Later, cancel up to four weeks before the contract ends.

GMX ProMail can be ordered only with a home address in Germany, Switzerland or Austria. GMX states that telephone support is exclusive to GMX ProMail and TopMail.

GMX Mail on the Web, Phone and Desktop

One account works in three ways: GMX webmail, a phone app and a desktop mail program. Each way has its own sign-in steps, covered in our login guide.

GMX Webmail in a Browser

GMX webmail needs no installation. GMX calls webmail safer than a mail program, because its filters and antivirus guard the account. You open the site for your language. The inbox, contacts, calendar, cloud and search share one window.

For alerts while you browse, GMX offers a free add-on called MailCheck for Chrome and Firefox. It shows unread items in the toolbar and can ring on arrival. It can watch several accounts, including other providers.

The Mail App

The free app runs on Android, iOS and iPadOS. GMX lists these features:

• Push alerts with a sound, vibration or LED light.
• Several GMX mailboxes in one app, plus outside ones added through the Mail Collector.
• An optional four-digit PIN lock.
• Optional encrypted messages, switched on once from a computer.
• Cloud access with automatic photo and video upload.

Old versions cannot sign in. Minimum versions are in our login guide. The app and GMX webmail reach the same mailbox.

Desktop Mail Programs

GMX describes no desktop program of its own. Outlook, Thunderbird and Apple Mail connect over POP3 or IMAP instead. GMX leaves that access switched off by default. You enable it in the account settings. Server names, ports and client steps are in our IMAP, POP3 and SMTP settings guide.

Spam Filter and Security Features

Shared and Personal Filters

GMX runs two filters at once. The shared one is tuned all the time by GMX's own team. It separates normal email from bulk mail with checksums. It looks for technical faults typical of junk, forged sender addresses, and servers or links on blocklists.

Screenshot: the shared filter article in the GMX help pages.

The second filter is yours. It learns when you press Spam or Not Spam. The sender then lands on your blocklist or allowlist. Your folder rules run first, so a rule can override those clicks.

You may also let GMX study the email you move between Inbox and Spam. The permission is optional. You can withdraw it in your settings.

Virus Protection

GMX scans all incoming and outgoing email, attachments included. Infected items are deleted, and you get a notice when mail meant for you is stopped. The protection is on by default. It can be switched off under Mail Security, though GMX advises that only in exceptional cases.

Two-Factor Sign-In

Once it is on, GMX webmail asks for your password and a six-digit code from an authenticator app. The code changes every 30 seconds. The phone app asks for the code once. A desktop program takes an app-specific password that you save once.

Encryption

The English security page advertises PGP. A Help Center article on encrypted communication carries a notice. Setting up encrypted messages and some GMX webmail settings are currently not possible. Read that article before you plan around PGP.

Where Your Mail Is Stored

The gmx.com site says data stays in Europe under European privacy standards. The FreeMail page on gmx.net says data is kept in Germany under German data protection.

Limits to Know Before You Rely on GMX Mail

• An address is final. To switch, create a new alias and delete the old one later.
• Registration needs a phone. It must be a mobile number that can receive texts. See the sign-up part of the login guide.
• Idle mailboxes are closed. The help articles describe deactivation after a long period without a login. Two articles give different periods, so sign in now and then.
• Outside access starts off. POP3 and IMAP also switch themselves off after long non-use.
• Phone help is a paid extra. TopMail and ProMail include it, while the free GMX plan has chat and a form.
• ProMail depends on residence. Ordering is open to residents of three countries only.
• FreeMail shows ads. GMX describes the German free plan as ad-funded.
• Junk vanishes after 30 days. Look through the Spam folder before then.
• Storage depends on the domain. The gmx.com side gives far more room than FreeMail.

GMX Free Email Compared With Other Free Email Services

Each number below comes from the provider's own site. Plans change often, so check before you pick a free email service.

Three details stand out. GMX and mail.com list the same storage, yet their attachment caps differ. FreeMail and WEB.DE show identical numbers. Proton's free tier also limits sending to 150 messages a day.

Emailing GMX Mailboxes? Verify Before You Send

Not every reader of this guide uses GMX. Some of you write to people who do. If your email list holds addresses at gmx.com, gmx.net, gmx.de or gmx.at, check them first.

GMX explains the two kinds of bounce in its Help Center. An error in the 500 range means the email can never be delivered. Typical texts are "mailbox unavailable" and "Unknown user". A "Mailbox full" notice sits in the same range. An error in the 400 range is temporary, and the email often arrives later.

Screenshot: the returned-mail article in GMX's help pages.

The same article advises its own senders against bulk mailings to addresses that are no longer valid or are unknown to them. Too many complaints can get a sending address flagged, and even deactivated. A check beforehand cuts that risk.

BillionVerify's email verifier tests one email or a whole list. Here is what to know:

• valid and invalid results cost 1 credit each, and unknown results are free
• a free re-check is available within 24 hours
• catch-all addresses get their own label and are not counted as valid
• the free tier adds 20 credits per active day, up to 600 a month, and they never expire
• a REST API, an MCP server and 25+ integrations are available
• the servers are in France (EU), and a DPA can be signed

BillionVerify checks an address in steps, from syntax to mail routing to the provider.

For a big list, use bulk email verification. Our reverse email lookup shows the domain and public profiles tied to an email, which helps when a GMX sender looks odd. If you collect phone numbers next to addresses, our phone checker shows whether a number is valid for its country. We make no claim about how GMX answers checks. Verify first, then send.

FAQs

Is GMX free email really free?

Yes. GMX free email carries no fee on either domain, though FreeMail is funded by ads. The gmx.com side is free too, and no paid tier showed up in our check.

How much storage does a GMX mailbox have?

An English-language mailbox has 65 GB, and FreeMail has 1 GB. GMX ProMail has 5 GB. TopMail has 10 GB plus 100 MB each month. GMX does not say why the domains differ.

What is the largest attachment GMX allows?

GMX caps attachments at 50 MB on gmx.com and 20 MB in FreeMail. ProMail also takes 50 MB, and TopMail takes 100 MB. For bigger files, GMX advises sharing a cloud link.

Can I use GMX webmail on a phone?

Yes, GMX webmail works in a phone browser. According to GMX, webmail runs on any device with an internet connection. The free app is the other route.

Does GMX Mail have a desktop program?

The GMX pages we checked mention none. Outlook and other mail programs can connect, once you switch on outside access in your settings.

Which apps does GMX Mail have?

GMX publishes a free app for Android phones, iPhones and iPads. It supports push alerts, several mailboxes, an optional PIN lock and cloud access.

What does GMX ProMail add to the free plan?

GMX ProMail adds 5 GB of mail room, a 50 MB attachment cap and 10 addresses. It also removes outside banners and brings support by email or telephone.

How much do the paid plans cost?

In October 2026, GMX ProMail is €3.99 per month and TopMail is €6.49 per month. Both start with a free month. Billing is every six months in advance, and the contract lasts 13 months with the test.

Can I get a gmx.com address with a gmx.net account?

Yes, but only with a paid plan. GMX lists @gmx.com among its premium endings.

What does the GMX spam filter do?

GMX's filters move unwanted email to the Spam folder. They check for known bulk mail, spam-like technical faults, forged senders and listed servers. Junk stays for 30 days.

Why is my GMX inbox full?

A GMX account is full when its storage is used up. Open Folder Overview to see the usage. Empty folders, add filter rules for unwanted senders, or lower the Trash retention time.

Can GMX Mail collect mail from other accounts?

Yes, the Mail Collector brings email from other providers into a GMX mailbox. GMX says up to 10 accounts can be connected. They also show in the app.

Should I verify GMX addresses before a campaign?

Yes, a check before sending finds typos and dead mailboxes in GMX addresses. A verifier such as BillionVerify labels each address valid, invalid, catch-all or unknown, and unknown results cost nothing.