Domain lookup

    t-online.de email verification

    Check whether an email address at the t-online.de domain is valid, deliverable and safe to send. Free single checks, no signup required.

    5 of 5 free checks left today — no signup required.

    Syntax check

    Confirms the address follows the correct format for t-online.de.

    MX & domain validation

    Verifies that t-online.de has active mail exchange records.

    SMTP mailbox test

    Checks the mailbox existence without sending an email.

    About the t-online.de mail provider

    Deutsche Telekom customer mail with strict inbound reputation checks.

    Provider
    Telekom
    Type
    Regional provider
    Catch-all
    no

    New to verification? Read the complete email verification guide or browse the full domain directory.

    Frequently asked questions

    How do I check if an email address at t-online.de is valid?

    Enter the address in the verifier above. VeriMailX checks the syntax, resolves the MX records for t-online.de, opens an SMTP conversation with the receiving mail server and reports whether the mailbox accepts mail — without sending an email.

    Is t-online.de a catch-all domain?

    Catch-all configuration is set by whoever administers t-online.de, and it can change at any time. A live verification tells you whether the server accepted the specific address or accepts everything, which is why catch-all status is reported per check rather than stored as a fixed value.

    Can I verify a bulk list of t-online.de addresses?

    Yes. Upload a CSV of up to 50,000 rows per file, or call the API for real-time checks at signup. Results include deliverability status, disposable and role-based flags, and a confidence score for each address.

    Verify email lists at scale

    Upload a CSV, connect via API or set up auto-revalidation for t-online.de and any other domain.

    Start free verification