We are here to help you get answers to your questions about OneSimCard phones and services.
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.
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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What Is the Difference Between "Direct Dial" and "Callback Dial" calling?
Direct Dial calling allows the caller to enter the international call prefix, country calling code and telephone number and then be directly connected to the person they are calling. This is how you dial when using your regular mobile service. Direct Dial Calling is standard on the OneSimCard Europe & More, OneSimCard Universal and eSIM.
Callback calling also allows the caller to enter the international call prefix, country calling code and telephone number. After the called number is entered, the user immediately receives an incoming call connecting the user to person called. Callback is very simple to use and allows for low cost calling on the OneSimCard Plus and OneSimCard Expedition (formerly Data & Roam). Callback does not increase the connection time. It is the same as with Direct Dial.
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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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 am traveling in Saudi Arabia and can receive calls, but I can't make an outgoing call. What should I do?
Local carriers in Saudi Arabia sometimes block standard OneSimCard outgoing calls. If this happens you need to either (a) enter a compatibility code into the settings of your phone or (b) initiate your call by sending an SMS message from the regular SMS menu (not the OneSimCard menu) of your phone.
How To Activate Compatibility Mode:
Bear in mind that if you have powered your telephone down and removed and reinstalled the battery, you will need to follow the programming steps outlined above again.
How To Deactivate Compatibility Mode:
How To Dial Without Activating Compatibility Mode:
Initiate your call by sending an SMS message from the regular SMS menu (not the OneSimCard menu) of your phone.
For example, to call from Saudi Arabia to Boston USA you should go to the SMS menu of the phone and send a message:
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There are no special instructions to receive calls in these countries.
Will a OneSimCard international SIM card work with my mobile phone?
OneSimCard will work with almost any unlocked GSM tri-band or quad-band cell phone. A partial list of compatible cell phones that we have tested can be viewed here.
If you need to unlock the phone, we suggest contacting your carrier or phone manufacturer for unlocking information or services.
If your phone is not a quad-band phone, please make sure that the bands of your phone are those required in the country of your travel. You can look it up here.
If you are still unsure whether your cell phone is compatible, contact support or purchase an international cell phone and SIM card bundle from us, which all come preloaded with our international SIM card, $10 balance and OneSimCard Apps Installed.
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.Can I be notified of missed calls when my phone is off or outside of a coverage area?
Yes, for Universal, Expedition, and eSIM World Sim Cards, you will receive SMS or email notifications when you miss a call due to your phone being off or out of coverage. SMS notifications are sent when the phone is unavailable for a period up to 4 hours. Email notifications are sent, regardless of the time period, to the email address you have entered into your online voicemail profile. Notifications will be sent when you make/receive a call or enter a new roaming country. NOTE: if the caller leaves a voicemail message then you will not receive this extra missed call notification.I have a OneSimCard SIM and my phone will not register on a roaming network, what's wrong?
Sometimes when moving from the USA, Canada or Mexico to another country, the SIM card will need to be reset to properly register on a new country roaming network.
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