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.
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 it free for someone to call my OneSimCard number using Viber?
Through a unique partnership with Viber, your primary OneSimCard number (+372) can be called free of charge for any Viber user! (requires activation and special dialing instructions, see below)
HOW: When this feature is activated, Viber users can call OneSimCard numbers for free by using a special dialing format +372800XXXXXXXX, where XXXXXXXX is the rest of the OneSimCard phone number after 372. For example, a OneSimCard user with the phone number +37212345678 should be called by dialing +37280012345678.
TO ACTIVATE: Log in to your OneSimCard account and go to the My SIM Cards menu. Scroll down to where it says "Incoming Viber Calls" and click Enable to activate this option.
COST: The call is free for the Viber user. The cost of receiving the Viber call is the same as receiving a call through a Personal Extra Number (PEN), i.e. the regular incoming call rate in the country you are in plus 20c/min. In countries with free incoming calls, like Italy or Japan, the cost will be just 20c/min.
PLEASE NOTE:
PLEASE NOTE: Viber is not available for the DataMax or DataMax eSIM
Do you offer an eSIM option for iPhones, Androids or Tablets?
Yes. The OneSimCard eSIM option is available for use with iOS and Android phones, smart watches and even Windows tablets.
eSIM is not a physical SIM, but rather a program that can be downloaded to eSIM compatible phones and device.
The list of supported devices includes:
iOS:
Apple iPad models with an eSIM:
Learn more about eSIM compatibility on the eSIM page.
Note: iPhonesmanufactured for the Chinese Market have 2 physical SIM card slots and are not eSIM capable. Pixel 3a can't use eSIM if the phone was purchased in Japan, or if bought with Verizon or Charter service.What is the cost of calling between two OneSim VoIP phones?
Calls between two OneSim VoIP phones are absolutely free.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.
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.
Is there a way to send a SMS to a short code number?
The SIM card does not offer SMS service to short code numbers
Can I send an SMS to or from a Common Access Number or Personal Extra Number?
You can't send SMS to a Common Access Number (CAN). Common Access Numbers and majority of Personal Extra Numbers are for Voice Calls only.
We recommend that SMS senders use our free online SMS or email-to-SMS functions as described in the user manual and our FAQs.
Note: US and Canada PEN can receive only actual mobile SMS from mobile phones. Alert and verification SMS sent from web sites like Google, Yahoo or your bank will not be delivered to US or Canada PENs due to the way these web sites send their messages.
If you require some alerts SMS sent from banks and other institutions, we offer special US-SMS Bank Verification PEN that will be able to receive SMS from mobile numbers as well as from institutions used for 2 step verification processes.
What is required to use the OneSim VoIP mobile application?
OneSimCard VoIP requires you to order a compatible Personal Extra Number (PEN). Most of the PENs we offer are OneSim VoIP enabled. You also need to have an Android phone with software version 8 or higher, or Apple device (iPhone, iPad, iPod Touch) with iOS 6.1 or higher.
Once you have an active OneSim VoIP enabled PEN, you will be able to see the option to create a OneSim VoIP account in the My SIM Cards menu of your online account. NB: YOU MUST create the 1SIM VoIP account in your account online on the "My SIM Cards" menu. Simply purchasing a PEN and downloading the mobile app DOES NOT create the VoIP account.
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.
There is no OneSimCard Menu (SIM Toolkit) in my Android phone. How can I fix this?
Some recent Android upgrades to versions 4.2.1 and 4.2.2 have a bug causing the OneSimCard Menu, labeled as SIM Toolkit, to be disabled.
If you do not see the SIM Toolkit app in your Android phone, please try doing the following:
Go to Settings>Security>Other Security Settings>Setup SIM Card Lock>Lock SIM Card. It will ask for the default SIM PIN. Enter 0000. Power off the phone and turn it back on. The SIM Toolkit app will then become available, though it might take 1-2 minutes for the phone to display it.
On Android version 5.1 go to Settings > SIM Cards > SIM Toolkit
Once you have access to the SIM Toolkit, select it, scroll down to Settings, enter 1101 and press confirm. Your phone will now be able to dial normally.
For eSIM cards, make certain that your eSIM is enabled.
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