We are here to help you get answers to your questions about OneSimCard phones and services.
Does OneSimCard offer a U.S. Military discount?
Yes! We offer a 15% discount (excluding airtime) for U.S. Military members when ordering with a verified .mil email address and entering promo code MILITARY15. This discount is only applicable for individual users, not for Corporate Accounts.What are the advantages of using OneSim VoIP?
The main advantages are significant cost savings and the ability to call from countries where there is no voice roaming coverage available, or for DataMax or DataMax eSIMs
OneSim VoiP can be used from any Android or Apple ( iOS) device to make international LD calls even when you are not traveling. OneSim VoIP does not require having OneSimCard SIM being installed in the phone. OneSim VoIP can be used with Wi-Fi or 3G/4G - no difference. You just need to have OneSimCard account with the SIM VoIP capable PEN. Calling using OneSim VoIP will cost most of the time less than any other way of calling.
OneSim VoIP is available with the following SIM cards: Plus, Expedition (formerly Data & Roam),  Europe & More, DataMax, and DataMax eSIM.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.
How do I enable roaming on my Android Phone?
This is very simple!ÂDoes iPhone Hotspot work with OneSimCard?
Yes. All unlocked iPhones' Hotspot feature works with OneSimCard SIM.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
What is an eSIM & how does it work?
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.When I dial following your instructions it does not work. What's wrong?
This answer applies to SIM cards purchased before January 1, 2017.
Some phones, such as Samsung, some Motorola, Android and Apple iPhones, require special dialing instructions or simple OneSimCard settings menu changes in order to make calls.
It is possible to make almost any phone entirely compatible, so you can call directly without using the OneSimCard menu or *146* by following these simple programming instructions below.
How to activate compatibility mode:
 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 or OneSimCard app and it looks like one of the apps.
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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.
If for any reason after entering compatibility code, you still do not get a ringback or you get the ringback the first time you make a call, but second time it would not work, please enter code 802 into the Service Code window instead of 1101 as provided above.
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iPhone users can download OneSimCard Assist App from iTunes that will takes care of the iphones compatibility issues, except for removing the ringback.
For example, calling to USA:Â Dial *146*0016175551212# and press the TALK (or SEND) button
The sequence *146* and # at the end can be used from any phone. However, most phones do not require it.
We strongly recommend you to watch very short video tutorials that will help you to understand how to make calls, SMS and data on your OneSimCard Phone.
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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.© 2006-2025 Belmont Telecom Inc., DBA OneSimCard.com. All rights reserved