We are here to help you get answers to your questions about OneSimCard phones and services.
Can I use OneSim VoIP over the Internet Data offered by OneSimCard SIM? Will it save me anything?
In countries where the cost of using mobile Internet Data is below 20 c/MB, the cost of using SIM VoIP over the data is comparable or less than the actual calling rate from the country.
As a rule of thumb, the SIM VoIP will use 1MB /Min of talk time. So, if the cost of Data in the country is 10 c/MB, then 1 minute SIM VoIP call will cost you 12 cents /minute. You need to have a 3G connection in order for SIM VoIP to work this way.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.
I have an Apple iPhone. When I dial following your instructions it does not work. What's wrong?
 1. Locate OneSimCard Menu.
 On iPhones it is called SIM Applications menu and is located under Settings- Phone menu
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 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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I just arrived in a foreign country and my phone is not working, what should I do?
If you left your phone on during your flight or cruise then you should fully power down and restart your phone. Once your phone powers back on it should automatically select an available roaming network.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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Can I check my Voice Mail from a phone other than my OneSimCard phone?
Yes. You can access the Voice Mail from other phones.Can I use OneSimCard service if my phone is locked?
Yes. There are a few options available if your phone is locked to the carrier that sold you the phone.
      http://www.onesimcard.com/international-cell-phones/
You can purchase a MI-FI device with aOneSimCard SIM card (Universal, Expedition or DataMax physical SIM card) at http://www.onesimcard.com/international-cell-phones/. The Mi-Fi device will provide your locked Android or iPhone with mobile data over Wi-Fi connection that you can use on your phone for Voice and Texts using SIM VOIP app, as well as data for web browsing, email, GPS navigation, etc.Does calling a mobile phone cost more than calling a landline?
It does not cost more to dial an international mobile number using OneSimCard service on traditional cellular connections. You will receive the same very low per minute rate whether calling to a mobile phone or to a land line.Â
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For OneSim VoIP, the cost of calling Mobile numbers is typically higher than calling landlines, but this method is still less than traditional voice calls in most countries..
You can find all rates listed on our Rates & Coverage page.
Is there a 911 emergency number in Europe that can be used with OneSimCard service?
Yes, in Europe the emergency number is 112. You can use 112 in Europe to report real emergencies to local authorities in the country of stay. The 3 digit number should be dialed directly without any additional digits in front of the number.
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For DataMax and DataMax eSIM SIM cards, while there is no voice calling feature without the use of 1SIM VoIP, which doesn’t support emergency calling, most cell phones ALWAYS allow you to call emergency numbers, even without a SIM inserted into the phone. In Europe the emergency number is 112. You can use 112 in Europe to report real emergencies to local authorities in the country of stay. The 3 digit number should be dialed directly using the regular phone app (NOT the OneSim VoIP App) without any additional digits in front of the number.
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