We are here to help you get answers to your questions about OneSimCard phones and services.
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 can I add airtime to my OneSimCard service?
In order to add airtime instantly, simply register a credit card with us on our website.
There are several ways to add airtime to your OneSimCard service.
Automatic Recharge - recommended:
From the phone using your credit card (Universal, Expedition and eSIM World only):
 For example, if you need to add $50 and the last 4 digits of the credit card registered with us is 8654:
You would dial 0988654*50 and press TALK. In few seconds you will get a confirmation message with your new balance.
* is a star character located on the keypad
From the phone using 1SIM Fund:
 a) From the phone dialpad dial 098YYYY*XX. Talk. YYYY -  4 digits PIN you created in 1SIM FUND menu. YY Amount from 25 to 99 USD
 For example, if you need to add $50 and the 1SIM FUND PIN is 8654:
You would dial 0988654*50 and press TALK. In few seconds you will get a confirmation message with your new balance.
* is a star character located on the keypad
From the OneSimCard.com web interface:
If you purchased a recharge PIN from OneSimCard Authorized dealer, you can recharge your account from OneSimCard handset from OneSimCard - Add Credit menu. When the Add Credit menu is selected, enter the 10-digit PIN and press the Talk (Send) button.Â
How long will it take for my OneSimCard to be delivered?
Your order will be shipped the next business day.
We offer several delivery options for shipments to the USA:
Your order should arrive in 1-5 business days,Tracking is available for US deliveries. It is not available for international deliveries.
Next day delivery to most locations in the USA
1-2 business days
For orders shipped outside of USA:
You will get more detailed information about the delivery to your destination when you start placing your order.
Any eSIM order does not require any shipping so this is a great way to avoid shipping costs and time. Just download and go!
Can I call using OneSim VoIP from countries where OneSimCard does not offer roaming coverage?
Yes. You can call from absolutely anywhere as long as you have a good Wi-Fi connection.What should I do if my OneSimCard phone or SIM card is lost or stolen?
If your phone or SIM card is lost or stolen and automatic recharge is on, this could be a serious problem.
To prevent this, log in to your account and activate the option to block your service immediately after you notice your phone or SIM card is missing. You can find this option in the My SIM Cards menu. Your OneSimCard service for this SIM card number will be instantly blocked. The remaining balance on your lost SIM can be transferred to another SIM card on your account or you can order a replacement SIM card if you would like to keep your phone numbers from the lost SIM. However, the existing data package can’t be transferred to the new SIM card.
Alternatively, you can contact customer service online or call 001-617-313-8888 for assistance.
Do international cell phones purchased from OneSimCard come with a warranty?
Unless otherwise noted, all phones sold on OneSimCard.com come with our standard 90-day replacement warranty. This warranty covers any mechanical defects, but does not include damage due to Acts of God, neglect, water damage, or other intentional or unintentional abuses of the phone. OneSimCard does offer extended warranties available for purchase.
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 a micro-SIM or Nano-SIM version of OneSimCard available for the Apple iPhone 4/4S, 5/5C,5S, 6, 6S, 7, 8, X, iPads and other devices?
We now offer SIM cards in universal sizes, where the SIM card contains all 3 sizes - Mini, Micro and Nano. Simply select the needed SIM version in the shopping cart.
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What are the advantages of using OneSim VoIP?
The main advantages are significant cost savings and the ability to call from countries where there is no voice roaming coverage available, or for DataMax or DataMax eSIMs
OneSim VoiP can be used from any Android or Apple ( iOS) device to make international LD calls even when you are not traveling. OneSim VoIP does not require having OneSimCard SIM being installed in the phone. OneSim VoIP can be used with Wi-Fi or 3G/4G - no difference. You just need to have OneSimCard account with the SIM VoIP capable PEN. Calling using OneSim VoIP will cost most of the time less than any other way of calling.
OneSim VoIP is available with the following SIM cards: Plus, Expedition (formerly Data & Roam),  Europe & More, DataMax, and DataMax eSIM.Can I use OneSimCard service if my phone is locked?
Yes. There are a few options available if your phone is locked to the carrier that sold you the phone.
      http://www.onesimcard.com/international-cell-phones/
You can purchase a MI-FI device with aOneSimCard SIM card (Universal, Expedition or DataMax physical SIM card) at http://www.onesimcard.com/international-cell-phones/. The Mi-Fi device will provide your locked Android or iPhone with mobile data over Wi-Fi connection that you can use on your phone for Voice and Texts using SIM VOIP app, as well as data for web browsing, email, GPS navigation, etc.© 2006-2026 Belmont Telecom Inc., DBA OneSimCard.com. All rights reserved