We are here to help you get answers to your questions about OneSimCard phones and services.
Can I check my Voice Mail from a phone other than my OneSimCard phone?
Yes. You can access the Voice Mail from other phones.Is there an eSIM App for Apple iOS and Android devices?
Yes. The 1Sim eSIM app is available at:
How do I make a call using OneSimCard global cell phone service?
To make a call:
With Europe & More, Univesal and eSIM World that do not use the callback to make a call, you will just get connected.
With OneSimCard Plus SIM or Expedition (formerly Data & Roam) SIMs:
After pressing the TALK/SEND button you will see a variable message on the screen (for example 'Wait for call') which you can ignore and your phone will ring back in a few seconds. Answer this ring as you normally would answer any incoming call. Your call will then be connected.
If you are unsure about how to properly dial an international number, follow this link for detailed country by country dialing instructions.
For Physical 3-in-1 DataMax, and DataMax eSIM cards, you can place calls using our low cost OneSIM VoIP service. OneSim VoIP costs much less than traditional voice roaming.
What is the cost to make calls from a OneSimCard phone to another OneSimCard phone?
It depends on the country you're in when making the call. In many countries there is a special low rate of just $0.25/min to call another OneSimCard phone (only when dialing the other OneSimCard user's primary mobile number, not a Personal Extra Number). In other countries your cost will be our standard low outgoing call rate from that country.
Example: two OneSimCard users are in Italy and one calls the other, the cost will be $0.25/min for the caller and free for the receiver.
Visit our Rates & Coverage page and choose any country to view its current rates. Use the dropdown menus to see rates for calling to/from other countries.
PLEASE NOTE: If you activate a discount call plan, the special rate to make OneSimCard-to-OneSimCard calls will not be available. You will be charged for those calls according to the discount call plan rate.
Another great benefit of using OneSim VoIP: To call using the 1SIM VoIP App to another user on the 1SIM VoIP App, this call is free, so long as you are calling the PEN associated with their 1SIM VoIP App.
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.
Do I need to activate the SIM card when my order is received or purchased from a retail store?
Yes, you will need to activate the SIM card once the order is received.
All OneSimCard international SIM cards and international cell phones with SIM cards are shipped inactive to prevent theft and improve security. Only the person who placed the order for OneSimCard service can activate it.
Activation is very simple: When you receive the SIM, just log in to your account at www.OneSimCard.com and click the large Activate button you will see in the middle of the screen.
Retail Customers: If you purchased your SIM card through an online or brick-and-mortar retail store, you should have received activation instructions inside the product packaging. To activate retail SIM cards, go to www.OneSimCard.com/Retail enter your new OneSimCard international mobile number and fill out the form to register and activate the SIM card. You will be provided specific instructions on the registration 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
How do I check my OneSimCard balance?
For Universal, Expedition, & eSIM World ONLY: Just dial 099 "Send" from your OneSimCard phone and in few minutes the balance will be displayed on the screen of your phone. Customers with iPhones can use OneSimCard Assist app to check balances and many other things.
You can always check your current balance by logging onto your OneSimCard account at www.onesimcard.com.
Does OneSimCard offer a U.S. Military discount?
Yes! We offer a 15% discount (excluding airtime) for U.S. Military members when ordering with a verified .mil email address and entering promo code MILITARY15. This discount is only applicable for individual users, not for Corporate Accounts.
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