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Esim and Overcharge

  • September 5, 2026
  • 3 Antworten
  • 21 Aufrufe
Besucher:in

I have a SIM card with O2 which gives me unlimited data in Germany and a set amount of Gigabytes in the rest of Europe. For the last two weeks I have been in Thailand. I have not used my data from my SIM card with O2 in the time I have been in Thailand, but I am being charged ridiculously high amounts of money by O2. I acquired an eSIM for my travels from an app called Saily and turned off my O2 SIM. Can you help me figure out why O2 is charging me significantly more than usual even though I have not used the data outside the EU or nearly as much as I would if I was in the EU the entire month? I have checked and my O2 Sim is not activated in my mobile service settings. I have also not received any calls or given any calls whilst here on mobile, only Whatsapp. Mein O2 app says I have not spent any data abroad. 

3 Antworten

Klaus_VoIP
Legende
  • Klaus_VoIPLegende
  • September 5, 2026

Since you don’t specify whether data or phone calls are the cause of these equally unknown charges, it’s hard to assess the situation. 
People often forget that just 10 minutes of roaming is enough to rack up nearly 60 euros in charges. A SIM card that’s actually turned off can’t incur any charges. If a foreign provider is now passing on charges to o2, then data was likely used. This happens when only data is disabled, when you switched to your eSIM too late, or when calls are forwarded to voicemail via an international number ...

Meine persönlichen Meinungsäußerungen als Kunde sind NICHT gesponsert und stellen nur meine unverblümte Meinung dar! Dafür erfolgen alle Inhalte pro bono publico. ;-)
    Besucher:in
    • vickster
    • Autor
    • Besucher:in
    • September 6, 2026

    Thanks for your answer. We are as unsure about the cause of the charges, the O2 app claims I have not used any data roaming outside the EU and I have not made or received any phone calls as I have completely turned off the O2 SIM line. I had also turned off roaming once I arrived at the airport, and used WiFi to acquire my eSIM at the airport. I am really frustrated and confused as I was traveling in the same place last year with the same data plan, and did not have any issues like this. 

    Klaus_VoIP
    Legende
    • Klaus_VoIPLegende
    • September 6, 2026

    In any case, the SIM card must have been active, because otherwise no foreign provider would be able to use the SIM number to bill o2!

    The bill must clearly indicate whether (forwarded) calls or data usage are the cause.

    How much was charged additionally for roaming?

    Meine persönlichen Meinungsäußerungen als Kunde sind NICHT gesponsert und stellen nur meine unverblümte Meinung dar! Dafür erfolgen alle Inhalte pro bono publico. ;-)
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