O2 Mail Login: Sign In, Webmail Addresses and Password Reset

The O2 mail login sits at mail.o2online.de. You type your name and your password into O2 Webmail and press "Anmelden". If the password is gone, a reset link starts the recovery.

This guide lists each login we could open and the current state of the service. It covers the password reset, mail program settings and login errors. Every fact about O2 comes from O2's own pages, read in October 2026. We did not register or sign in, and we are not affiliated with O2 or Telefónica. BillionVerify is an email verification service. For a short definition of mailbox hosting, read what email hosting is in our glossary.

Key facts (checked October 2026):

• The O2 Webmail sign-in at mail.o2online.de asks for "E-Mail" and "Passwort" and offers a "Passwort vergessen?" link.
• O2 staff member o2_Emanuel writes on the help site that the service is only available with contracts concluded before 13 December 2012.
• O2's service page says the domains alice-dsl.net, alice-dsl.de and alice.de were switched off on 15 January 2023, while each mailbox stays reachable under its @o2mail.de name.
• A pinned community post, edited by moderators, warns that 180 days without use can lead to deactivation.
• The same post names admin.o2mail.de as the control panel for landline and DSL addresses, and mailadmin.o2online.de/portal/ for mobile contracts.
• BillionVerify's account gives 20 free credits on each day you use it, with no card needed, for checking addresses ahead of a send.

Is the Service Still Running?

We found no notice that O2 closed the service. O2 Webmail still loads, and O2 still publishes server settings, last updated in October 2024.

The offer is old and small. Each account was tied to the original contract. O2 email accounts under the names Alice, loop, o2mail and o2online all came from earlier providers that O2 took over.

The pinned post's author adds a personal view. Keep a backup of your mail, and pick a provider whose core business is email for anything important.

Every O2 Webmail Login Address

Several hosts lead to the login or to the admin panel. The table lists what we opened.

The two panels look identical, says the pinned post, yet each works only with matching accounts. Older community replies also mention gomail.o2online.de for mobile contracts. We opened it from outside Germany, and it answered "Not Authorized to View This Page".

The O2 Webmail Login Page

The form is plain. It has the title "Webmail", a box for "E-Mail", a box for "Passwort" and a blue button. Under the button sits the reset link. A language menu and the links "Impressum" and "Datenschutz" finish it.

Screenshot: O2's Webmail form, opened without signing in.

Which Name to Type

The server settings page explains the name. For an @o2online.de mailbox, it is the contract's phone number. Some landline contracts use a self-chosen name. A typical entry reads 01761234567@o2online.de, and @o2mail.de works alike.

So your O2 email login is the full name with its ending, paired with the mailbox password. Webmail can also reveal your settings.

Alice Mail Login After the Switch

The service page "Abschaltung der Alice E-Mail-Domains" explains the Alice change. Senders can no longer reach an Alice alias. For the Alice mail login, use the @o2mail.de name instead. The password did not change.

Screenshot: O2's notice about the Alice domains.

O2 asks Alice users to do four things:

1. Open the Webmail settings and switch sender and reply name to the @o2mail.de one.
2. Tell your contacts, for example with an automatic reply.
3. Update every online account that still uses the old one.
4. Change the entry in Outlook, Thunderbird or Apple Mail, and in your password manager.

In September 2025, an O2 moderator wrote that sign-in limits for @alice-dsl.net, @alice.de and @hanse.net were fixed. Owners of @genion.de and @loop.de can try the @o2online.de ending, the moderator added. That tip helps when an old ending refuses your password.

O2 Mail Sign Up

We found no registration page for new accounts, on o2online.de or in the community. The cutoff above explains why. A newer contract does not come with an O2 email box.

If your contract is newer, this guide cannot give you one. Other German providers publish their own sign-up pages. See our guides to the WEB.DE login and the mail.de login.

Password Reset for O2 Mail

The reset starts on the login form, one click away.

1. In O2 Webmail, choose "Passwort vergessen?".
2. Under "Schritt 1: Kontoanmeldung", enter your full name.
3. Type the characters shown in the picture. An "Audio" button reads them out.
4. Click "Weiter". "Abbrechen" takes you back.

The admin panel has its own reset link. We followed it from admin.o2mail.de, and it opened the same form on webmail.o2mail.de.

Screenshot: the panel at admin.o2mail.de.

Set Up Recovery First

Each address needs its own security question. You store it in Webmail, and only then does the reset work. Without one, the pinned post points you to the hotline.

The same post says the panel can show the passwords of single accounts. That is a second way back, if the panel still opens.

If Nothing Is Stored

Then the service team takes over. The hotline is 089 78 79 79 40 0, open Monday to Friday 7 to 20 hours and Saturday 10 to 18 hours on working days. Calls follow your plan's rates.

In one help thread, a moderator wrote that the specialist department had mailed a letter with a new password. Keep your postal details current in your customer account, or the letter goes astray.

Choose a Safe New Password

Server setups differ, so stay with ASCII characters. Umlauts can cause trouble in passwords and in names, the post warns.

Mail Programs and Server Settings

O2 recommends IMAP for any program, because it keeps mail on the server. You can, for instance, move spam without downloading it. The program must support SMTP authentication. Switch on "Server erfordert Authentifizierung".

The username is the full name, such as your number plus @o2online.de or @o2mail.de.

Screenshot: O2's help page for program settings.

The page also lists plain ports for POP3 (110) and SMTP (25 or 1025). Choose the encrypted ports where you can.

A client may still show Alice server names after the change. O2 says it must be updated to mail.o2mail.de.

When the Login Fails

Helpers on the community site ask the same questions first. They narrow the cause quickly:

• When did you last sign in? Some accounts run on, but none is safe.
• Does the original contract exist, and is it DSL, mobile or prepaid?
• Can you reach the admin panel for your contract type?
• Does the Webmail login open?
• Does a program fail, or only the browser? If the Webmail login works, the account is fine and the program is at fault.

Check the Ending

Some endings had trouble in 2025. If an old ending fails, try @o2mail.de or @o2online.de with the same password. Moderators named that route in the help threads.

Where to Ask O2

O2 offers hotlines, a live chat, a contact form, a WhatsApp service and the O2 Community. Moderators can file fault reports, adds the pinned post, and both routes need patience.

Emailing O2 Mail Users? Verify Before You Send

Not everyone reading this guide owns an O2 email inbox. Some of you send to people who do. These accounts belong to old contracts, so a list with @o2mail.de, @o2online.de or Alice entries can hold dead ones.

The Alice case is documented. A moderator post says mail to those addresses is no longer delivered, and senders learn that the mailbox does not exist. Each one ends up as a bounce in your report.

BillionVerify cleans a whole list and reports one result per entry.

BillionVerify's email verifier works on single entries, and bulk email verification works on lists. 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 entries get their own label and are not counted as valid
• the free allowance is 20 credits per day of use, up to 600 a month, and credits never expire
• our servers are in France (EU), and a DPA can be signed

We make no claim about how O2's servers answer checks. If your signup form collects phone numbers, our phone number checker shows whether a number is valid for its country. To trace the owner of a suspicious sender, use our reverse email lookup. Another operator that moved old addresses is covered in our guide to the Vodafone, Arcor and Kabelmail login.

FAQs

What is the O2 mail login page for?

It takes a name and its password, and lives under the host name mail.o2online.de. The same account also works in mail programs.

Can I still open a new O2 email address?

New accounts are not offered, as far as O2's pages show. We found no sign-up page, and O2 ties the service to old contracts. Customers with newer contracts need another provider.

Which username does O2 mail use?

For an @o2online.de account, O2 names the contract's number. Programs want the full name, and the web form asks for it in the first box.

What if I forgot my O2 mail password?

Click "Passwort vergessen?" and follow the steps, which need a stored security question. Without one, the hotline must help, and a new password may come by letter.

Do Alice email addresses still work?

Alice addresses stopped working in January 2023, because O2 switched off those domains. The mailbox lives on under its @o2mail.de name with the same password. Sign in with that name.

Does O2 mail work in Outlook or Thunderbird?

Yes, O2 describes setups for any mail program and recommends IMAP. The host differs by ending, as the table above shows. Sending needs authentication switched on.

Does O2 delete an unused account?

A long pause risks deactivation, though some accounts keep running. Sign in now and then, and keep a copy of important mail elsewhere.