We are here to help you get answers to your questions about OneSimCard phones and services.
Can eSIM be used for Data, Calls and Texts?
Yes, as of March 3rd, 2020, OneSimCard eSIM can be used for Mobile Data, Voice and Texts. However, you can still use the OneSim VOIP app option with a Personal Extra Number (PEN) for additional savings on calling and texting
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For DataMax eSIMs, only Data is available. However, you can use our OneSim VoIP app for cost effective voice and SMS communication.
Are there any additional roaming charges?
There are NO additional roaming charges. The rates you see listed on our Rates & Coverage page are the only rates you will be charged when making or receiving calls on your OneSimCard enabled cell phone. This is true for using regular cellular voice or 1SIM VoIP App.I have more than one Personal Extra Number (PEN). Can I use different PENs for OneSim VoIP?
If you have more than one OneSim VoIP enabled PEN you can switch between these PENs for the purpose of the OneSim VoIP account. This option is available in the My SIM Cards menu in your online account.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.Which phone number will be shown on the caller ID when I make a call using OneSim VoIP?
Your active OneSim VoIP Personal Extra Number (PEN) will be shown on the caller ID.I can make calls through OneSim VoIP. However incoming calls are going through my roaming SIM. What's wrong?
If your incoming calls are not being routed through the OneSim VoIP app then you are either not connected to Wi-Fi or the OneSim VoIP app is not active.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.
Is text messaging available on the OneSim VoIP App?
OneSimCard SIM VoIP users with US and Canadian numbers may now send and receive text messages over the OneSim VoIP app on iPhone and Android. The cost to sending a message is $0.05 per text to most countries. Receiving message is $0.05. Â
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OneSimCard SIM VoIP users with US and Canadian numbers may now send and receive text messages over the OneSim VoIP app on iPhone. The cost to send or receive each message is $0.05.Â
How many times can I install an eSIM, and can it be installed on different devices?
For DataMax eSIM can be installed once.I used a large amount of data  even though I barely used data, what happened?
Each mobile data session is charged for a minimum of 10kB usage. Even if you check just one 3k email you will be charged for 10kB of usage. In some countries this can be over 30¢ per session, however in Europe and elsewhere it can be as little as 1¢. Check all rates.
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Each mobile data session is charged for a minimum of 100kB usage. Even if you check just one 3k email you will be charged for 100kB of usage.
Please note: Some phones, like iPhones, Androids, and other smartphones, can access data without you even knowing it if you have data enabled. We strongly recommend checking the settings on your phone and disable mobile data roaming if you will not be needing data service. By default, all SIM cards are pre-programmed with data service enabled, once you activate your data package.
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