We are here to help you get answers to your questions about OneSimCard phones and services.
Can I call using OneSim VoIP from countries where OneSimCard does not offer roaming coverage?
Yes. You can call from absolutely anywhere as long as you have a good Wi-Fi connection.I just activated my SIM card and can't make a successful test call. What's wrong?
If you just activated your SIM card and can not make a test call by following the instructions in the user manual, you will likely just need to power off the phone and power it back on again. The phone should automatically re-register with one of our partner networks. Remember, if you answer the test call when it rings you will be charged for the call.Do I need to have a OneSimCard SIM card installed in my phone to use OneSim VoIP?
No. OneSimCard SIM is not required to be installed in the phone for OneSim VoIP to be used. However, you do need to have OneSimCard account with a VoIP capable PEN.Do you offer an eSIM option for iPhones, Androids or Tablets?
Yes. The OneSimCard eSIM option is available for use with iOS and Android phones, smart watches and even Windows tablets.
eSIM is not a physical SIM, but rather a program that can be downloaded to eSIM compatible phones and device.
The list of supported devices includes:
iOS:
Apple iPad models with an eSIM:
Learn more about eSIM compatibility on the eSIM page.
 Note: iPhonesmanufactured for the Chinese Market have 2 physical SIM card slots and are not eSIM capable. Pixel 3a can't use eSIM if the phone was purchased in Japan, or if bought with Verizon or Charter service.What should I do if my OneSimCard phone or SIM card is lost or stolen?
If your phone or SIM card is lost or stolen and automatic recharge is on, this could be a serious problem.
To prevent this, log in to your account and activate the option to block your service immediately after you notice your phone or SIM card is missing. You can find this option in the My SIM Cards menu. Your OneSimCard service for this SIM card number will be instantly blocked. The remaining balance on your lost SIM can be transferred to another SIM card on your account or you can order a replacement SIM card if you would like to keep your phone numbers from the lost SIM. However, the existing data package can’t be transferred to the new SIM card.
Alternatively, you can contact customer service online or call 001-617-313-8888 for assistance.
When I make a call using OneSim VoIP the quality of the call is not as good as the quality of the regular roaming connection. Can this be improved?
The quality of a OneSim VoIP call is only defined by the quality of your Wi-Fi connection. This is the part of the connection that we can not control. Quality of the Wi-Fi connection is defined by many parameters, rather than just by the speed of the connection. With a good Wi-Fi connection the quality of the call will be similar to using our regular roaming network.Does voicemail work with OneSim VoIP?
Yes. If you are not available to answer the OneSim VoIP call or if the OneSim VoIP app is turned off, the call will be routed through our standard roaming network. If the call is not answered it will be sent to your OneSimCard voicemail box.Â
NOTE: Voicemail is not available for DataMax or DataMax eSIM cards with OneSim VoIP.
How does OneSim VoIP work when the call is received?
When someone dials your OneSim VoIP enabled Personal Extra Number (PEN), the system will first check if your OneSimCard phone is registered with the OneSim VoIP app on a Wi-Fi network. If it is registered, the call will be sent using VoIP. If the OneSim VoIP app is not running or it is not registered on a Wi-Fi network, then the call will be sent using the standard OneSimCard roaming network and charged our standard roaming rates.When making an outgoing call how do I select which way the call should go: through regular roaming or through OneSim VoIP?
To make an outgoing call using OneSim VoIP, you need to be registered on a Wi-Fi network and have the OneSim VoIP app running on your phone. You should make the call using the OneSim VoIP app dial pad. To make a call the regular roaming way,you should make a call from your regular phone dial pad.Â
NOTE: Regular roaming calling is NOT available on DataMax or DataMax eSIM cards. To use voice you will need to use the OneSim VoIP app
Can I move balances from one SIM card to another?
We allow moving balances from one SIM card to another in the following cases:
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