We are here to help you get answers to your questions about OneSimCard phones and services.
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.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.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
When I try to make a call, I get a message 'Call is modified and cannot be made'. What does that mean?
Some phone models do not allow direct dialing with older OneSimCard SIMs sold before January 1, 2017.
To get around this problem, you should try either of these methods:
* is a star character located on the keypad
Other examples of how to use the *146* dialing prefix if necessary:
The prefix *146* and # at the end can be used from any phone. However, newer OneSimCard SIM do not require it and you should be able to dial codes directly, 091, 094, 095, 099 or 098XXXX*XX Talk.
If you have an older SIM and the dialing does not work without entering *146*, please follow these simple instructions to remove the need to dial *146*:
How to activate compatibility mode:
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 1. Locate OneSimCard Menu.
 On iPhones it is called SIM Applications menu and is located under Settings- Phone menu
     On Androids it is called SIM Toolkit app and it looks like one of the apps
Newer SIM Cards: Select Compatibility option and make sure "On" is selected
Older SIM Cards: After selecting Settings:
Bear in mind that if you have powered your telephone down, and have removed and reinstalled the battery, you will need to follow the programming steps outlined above, again.
When dialed directly, some Nokia and other phones can display message: "Call is not allowed" or "Call is barred". Just ignore this message and wait for the ring-back for 10 seconds or so.
Can I use Facetime, WhatsApp, Telegram, Discord, iMessage, and other messaging Apps with eSIM?
For DataMax eSIM, you can use these Apps as you already do. Please ensure your messaging account is already setup with your primary carrier’s phone number because you cannot sign up for these services with the DataMax eSIM number.
Additionally, the eSIM data service can be used for the actual data part of your communications. So, when you are installing eSIM on phone, you can select the Primary service for Facetime and iMessage and then if your selected eSIM to be your primary data service, the communications will go over eSIM mobile data.
Do I need to have Data Roaming turned on for eSIM to work?
Yes. Data Roaming should be enabled on your phone for eSIM for data to work. Calls and texts on eSIM World should work with or without it.
What is an eSIM & how does it work?
How do I install my eSIM?
Before purchasing, please ensure you have verified that your device is unlocked and one of the supported devices. Installation is completed by using your phone to scan the QR code of the purchased eSIM. You may scan the QR code by displaying it on the computer screen, another device, or a printed copy. You can also "scan" the QR code without needing a second device using the QR code we emailed to you. You can see instructions for this here:
Install eSIM without a second device for iPhone instructions
Install eSIM without a second device for Android instructions
If you’ve already purchased OneSimCard eSIM, you can see full installation instructions and access your QR code from the Recharge menu in your online account. Make sure eSIM is selected in the Select SIM Card drop down menu.
If you have not purchased your eSIM yet, learn more about international eSIM here.
How much does it cost to receive a call with OneSimCard?
For Universal, Expedition, and eSIM World SIM cards, receiving calls is free in over 150 countries when received on your primary European phone number, including in most of Europe. To receive a call on your U.S. number or other Personal Extra Number, there is an additional per minute rate added. View all international cell phone rates.
If you receive a call through a Common Access Number or Personal Extra Number (such as a U.S. number) there is an additional charge of 20c/min. In countries with free incoming calls this would be your only charge per call.
For DataMax and DataMax eSIM card types, you can make and complete calls for a fraction of the cost of traditional cellular roaming (including on tablets) using the 1SIM VoIP App available on Google’s Play Store and Apple’s App Store:
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Apple App Store:Â http://itunes.apple.com/us/app/onesim-voip/id510371587
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For Universal, Expedition, and eSIM World SIM cards, Â all incoming SMS text messages are free to receive when received on your primary European number. Add 9 cent per SMS when receiving text on US or Canada PEN.
For DataMax and DataMax eSIM SMS messages are sent and received using the 1SIM VoIP App. The cost to receive SMS using the 1SIM VoIP App is $0.05 in most countries, The cost to send an SMS using 1SIM Voip App is $0.10 in most countries. See all rates on our international cell phone rates page.
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How do I prevent the service from expiring?
The OneSimCard phone number has no expiration, provided you made at least 1 call or sent an SMS once every 12 months.
However, the funds on the SIM expire 10 months after your last recharge. The minimum recharge amount is $25. You can keep the balance from expiring by simply recharging at least once every 10 months. If you let your balance expire, then all you need to do to get the service up and running again is to log in and add funds to your SIM card. Automatic recharge will be canceled if you let your funds expire.
NOTE: For Physical 3-in-1Â DataMax & DataMax eSIM SIM cards, if the SIM card has no balance, the SIM will expire and be removed from the account after 7 days, unless there is a data package currently active on the SIM (not a future activation). If there is no balance on the SIM and the active data package expires, the SIM will expire 7 days following the expiration of the active data package.
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An expired SIM can be restored for a $10.00 restoration fee plus a recharge of at least $25.00.
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