We are here to help you get answers to your questions about OneSimCard phones and services.
Will I get a bill for using OneSimCard service?
No. DataMax, DataMax eSIM, OneSimCard Universal, Expedition and eSIM World service is a prepaid service. You will not be able to spend more than you put on the SIM, except when you set the automatic recharge of the SIM. There are three simple ways to add funds to the balance of the SIM: from on-line, from the mobile phone and by setting up an automatic recharge. This pertains to both - purchased SIM cards.
For funding the 1SIM VoIP App, there are three simple ways to add funds to the balance of the account: from on-line, from the mobile phone and by setting up an automatic recharge.
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.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 should I send an SMS to get charged only 15 cents per text message?
There are two ways for SMS message to be sent:
Bear in mind that sending SMS messages to the abbreviated special SMS destinations like voting, music downloads, etc. will cost you $9.00 per message.
This does not apply to DataMax SIM cards.
How much does it cost someone in the US or Canada to call to my OneSimCard cell phone?
For Universal, Expedition, and eSIM World SIM cards, many U.S. and Canadian carriers can charge more than $3/minute to connect to an Estonian mobile number, the primary mobile number for a OneSimCard global SIM card. Your SIM card includes a U.S. number which will be much less expensive for people to call.
Callers can also use one of the Common Access Numbers (CAN) that we provide to you free of charge in more than 10 countries. Your OneSimCard account will simply be charged an additional 20c/min to the incoming rate in the country you are in to receive those calls. There is also the option of ordering a dedicated Personal Extra Number (PEN) in Canada and many other countries that will forward all calls directly to your OneSimCard cell phone. You can see the list of countries where PENs are available here:
You can order a Personal Extra Number when placing your order or later at any time by logging in to your account. Visit our Rates & Coverage page and choose any country to view all rates.
If you would prefer for the caller to pay for calls made, we recommend they buy Peanuts Prepaid. Using this service would guarantee a connection to your OneSimCard mobile phone from the U.S and Canada for 20c/min and it is very easy to use without switching your LD carrier.
For Physical 3-in-1 DataMax and DataMax eSIM, if you chose to use SIM VOIP app, your friends and family will call the PEN number you are assigned, so in most cases, there will be no tariff for them to call you, and the cost to receive the call is only $0.01/Minute.
Do I need to change any settings on my phone when going abroad?
Not Really. If you are planning to use Mobile Data, you will need to enable Data Roaming on your phone. Everything else in modern phones get done automatically. However, you should ensure that the APN on the device is correctly updated when the SIM card or eSIM card is enabled.Universal, Expedition, & eSIM World SIM card types:
Name: 1SIM
APN: send.ee
Leave all other settings alone
DataMax, DataMax eSIM, & IoT Track SIM card types
Name: 1SIM (NOTE: Most IoT devices do NOT have a setting/field for “Name”)
APN : OSC (NOTE: The “O” is the LETTER O, NOT the number 0)
Leave all other settings alone
Yes. Your Universal, Expedition and eSIM World OneSimCard mobile number can currently be forwarded to EU, Canada, USA, Russia, Ukraine and Belarus numbers. It's 100% free to forward your OneSimCard phone number to many countries including to U.S. or Canadian numbers. Forwarding to some countries, as well as to satellite phones, will carry a forwarding charge as listed in the Rates & Coverage page on OneSimCard.com.
To enable/disable call forwarding from your online account:
Log in at OneSimCard.com and go to the My SIM Cards menu. Select your SIM card number and enable/disable Call Forwarding on this screen.
To enable/disable call forwarding from your phone:
Dial *146*081*XXXXXXXXXXXXX# and press Send/Talk (where XXXXXXXXXXXXX is the forward-to number in international format: 00+countrycode+number)
Newer SIM cards use *81* instead of *081*
Example: to forward to U.S. number 1-617-555-1212, dial *146*081*0016175551212# and press Send/Talk.
If you get an "Unknown Format?" message, dial *146*81*0016175551212#
To disable call forwarding, dial *146*080# and press Send/Talk. If you get an "Unknown Format?" message dial *146*80# and press Send/Talk.
I can make calls through OneSim VoIP. However incoming calls are going through my roaming SIM. What's wrong?
If your incoming calls are not being routed through the OneSim VoIP app then you are either not connected to Wi-Fi or the OneSim VoIP app is not active.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
Where can I find the settings required to be entered into the OneSim VoIP app?
Once you create the OneSim VoIP account, you will be emailed settings and instructions. You can also see the settings in the My SIM Cards menu of your online account.© 2006-2025 Belmont Telecom Inc., DBA OneSimCard.com. All rights reserved