We are here to help you get answers to your questions about OneSimCard phones and services.
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 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.
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.Do I need to have a OneSimCard SIM card installed in my phone to use OneSim VoIP?
No. OneSimCard SIM is not required to be installed in the phone for OneSim VoIP to be used. However, you do need to have OneSimCard account with a VoIP capable PEN.Can I install my OneSimCard eSIM more than once?
You can re-install the eSIM on the same phone up to 10 times. eSIM 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.Can I transfer my phone numbers and balance from my standard OneSimCard SIM when I upgrade to a OneSimCard Plus SIM or other SIM card?
Is there an eSIM App for Apple iOS and Android devices?
Yes. The 1Sim eSIM app is available at:Is there a monthly or 30-day credit card spending limit for OneSimCard service?
Yes. To reduce fraud and to protect you from over-spending, there is 30-day credit card spending limit set for each individual account. You will only be able to charge up to a certain amount during any 30-day period. You can see your current limit by logging in to your OneSimCard account and going to the Purchase History menu. There, you will find a Credit Card Authorization form available for download. If you would like to increase your monthly credit card spending limit, please download the Authorization form and submit it back to OneSimCard as instructed on the form.
We strongly suggest that you set your monthly credit card limit before going overseas as dealing with the form on the road can be much more difficult.Â
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.
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.
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