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.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.Can I keep receiving calls made to my regular cell phone or landline numbers while traveling abroad?
Yes, you can easily forward calls from your regular cell phone number, home phone, office, etc. to your OneSimCard phone while you're abroad!
Your OneSimCard international Universal and Expedition SIM card comes with both a European and U.S. number. To forward your regular U.S. numbers to the SIM, just set them to forward to the U.S. number that's included with your SIM card. For eSIM World and DataMax eSIM, you can order Personal Extra Numbers (PENs) as needed for an additional cost.
You can also order unlimited Personal Extra Numbers (PEN) - Local or Toll Free - in many different countries, including USA, Canada, UK, France, Italy and Spain. For example, if you work or live in the UK and want to keep receiving calls made to your regular UK numbers, just add a UK PEN to your SIM card and set up call forwarding to that new number.
Calls received through a PEN will be charged an additional 20c/min to the incoming rate of the country you are in. The exception is calls received through a UK-Mobile PEN which is only charged an additional 25c per call.
Please Note:Â Your subscription to a Personal Extra Number starts the moment your order is shipped. If you do not need your PEN to be active right away, you can always wait and order a PEN later at any time by logging in to your account.
You can forward your calls to your 1SIM VoIP PEN. Simply forward all calls from your phone number to your 1SIM VoIP PEN using the directions below. Normal charges will apply for receiving calls to your 1SIM VoIP number (there will be NO extra $0.20, or $0.25 for UK PEN, cost to receive a call on OneSim VoIP).
Different carriers use different ways of programming call forwarding. Below are instructions to setup call forwarding with various US wireless carriers. We urge you to test the call forwarding a few days prior to your trip, and to call your wireless carrier for assistance if needed.
Alltel, , Verizon Wireless, Cricket Wireless
To activate Call Forwarding:
* is a star character located on the keypad
To deactivate Call Forwarding:
T-Mobile and AT&T Wireless GSM phones
To activate Call Forwarding:
To deactivate Call Forwarding:
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Can I install my OneSimCard eSIM more than once?
You can re-install the eSIM World and Asiana on the same phone up to 10 times. These eSIMs can be installed only on one device. Once installed, it's not possible move that eSIM to another device. If you need to install eSIM on another phone, please order a new eSIM. Balance and PEN(s) from the old eSIM can be moved to a new eSIM at your request.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.
What is an eSIM & how does it work?
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.
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.
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.
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