We are here to help you get answers to your questions about OneSimCard phones and services.
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.
What is an eSIM & how does it work?
Can I install my OneSimCard eSIM more than once?
You can re-install the eSIM World and Asiana on the same phone up to 10 times. These eSIMs 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.Is text messaging available on the OneSim VoIP App?
OneSimCard SIM VoIP users with US and Canadian numbers may now send and receive text messages over the OneSim VoIP app on iPhone and Android. The cost to sending a message is $0.05 per text to most countries. Receiving message is $0.05. Â
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OneSimCard SIM VoIP users with US and Canadian numbers may now send and receive text messages over the OneSim VoIP app on iPhone. The cost to send or receive each message is $0.05.Â
How do I set up SMS text messaging on my phone?
SMS messaging usually works without any additional setup of the phone.
In rare cases when there are issues sending or receiving text messages, please look at the following:
Problem with Sending SMS:
SMSC number should be set as follows:
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1. For Standard  and Plus OneSimCard SIM: +3725099000 for all countries except:
a. China:  +85290296747
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2. For the Expedition (former Data & Roam) SIM as well as for Europe & More SIM: +37256100041
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Special instructions for Apple Phones:
With Apple iPhones to check SMSC:
From the phone dialer Dial *#5005*7672#Â
You will see the SMSC set currently on the phone.Â
To change the SMSC on Iphone dial:Â
Plus and Standard SIMs: **5005*7672*+3725099000# for all countries except China and **5005*7672*+85290296747# if in China.
Expedition (formerly Data & Roam) and Europe & More SIMs in any country:Â **5005*7672*+37256100041#
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If your phone requires the name of Message Center Name enter: SMSC
SMS lifetime is short - must be at least 2 hours or set to Maximum settings.
Try sending SMS from OneSimCard menu
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 Problem with Receiving SMS:
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.
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.
What is your Return/Refund policy?
We do not give refunds for airtime.
You may return an unused phone or OneSimCard SIM card within 30 days after our shipment of the item to you, provided you never placed a call to or from the mobile phone issued, all airtime is intact and the phone or OneSimCard SIM card is in new condition, in the original factory carton, including all packaging materials, inserts and manuals, warranty cards (not filled-out) and all related accessories. A 25% restocking fee will be applied, and shipping charges will not be refunded. Returned merchandise will not be accepted unless a Return Merchandise Authorization (an RMA) has been requested and issued by our Customer Support department. The RMA number must be clearly written on the outside of the box in order to be processed.
We will not refund airtime used on mis-dialed calls. If you are not sure how to dial a number in a specific country, please request support from customer service.
There are no refunds for sent SMS messages - either it was delivered to the recipient or not. Not all SMS messages can be or will be delivered.
We will not refund minutes used for calls to Customer Service. A call made to Customer Service will be billed at the same rate as a regular call made from the country in which you are located.
There will be no refunds for expired SIM Cards, even if, at the time of expiration, your SIM Card Account had a positive balance.
There will be no refunds for expired SIM Card Account balances should you fail to recharge your account with at least a $25 payment within ten (10) months of your preceding $25 recharge.Â
There will be no refunds of your account balance if you terminate the Service.
There will be no charge to your prepaid account if you do not answer the call back. Contact OneSimCard Customer Support for more help.
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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.
Can I keep receiving calls made to my regular cell phone or landline numbers while traveling abroad?
Yes, you can easily forward calls from your regular cell phone number, home phone, office, etc. to your OneSimCard phone while you're abroad!
Your OneSimCard international Universal and Expedition SIM card comes with both a European and U.S. number. To forward your regular U.S. numbers to the SIM, just set them to forward to the U.S. number that's included with your SIM card. For eSIM World and DataMax eSIM, you can order Personal Extra Numbers (PENs) as needed for an additional cost.
You can also order unlimited Personal Extra Numbers (PEN) - Local or Toll Free - in many different countries, including USA, Canada, UK, France, Italy and Spain. For example, if you work or live in the UK and want to keep receiving calls made to your regular UK numbers, just add a UK PEN to your SIM card and set up call forwarding to that new number.
Calls received through a PEN will be charged an additional 20c/min to the incoming rate of the country you are in. The exception is calls received through a UK-Mobile PEN which is only charged an additional 25c per call.
Please Note:Â Your subscription to a Personal Extra Number starts the moment your order is shipped. If you do not need your PEN to be active right away, you can always wait and order a PEN later at any time by logging in to your account.
You can forward your calls to your 1SIM VoIP PEN. Simply forward all calls from your phone number to your 1SIM VoIP PEN using the directions below. Normal charges will apply for receiving calls to your 1SIM VoIP number (there will be NO extra $0.20, or $0.25 for UK PEN, cost to receive a call on OneSim VoIP).
Different carriers use different ways of programming call forwarding. Below are instructions to setup call forwarding with various US wireless carriers. We urge you to test the call forwarding a few days prior to your trip, and to call your wireless carrier for assistance if needed.
Alltel, , Verizon Wireless, Cricket Wireless
To activate Call Forwarding:
* is a star character located on the keypad
To deactivate Call Forwarding:
T-Mobile and AT&T Wireless GSM phones
To activate Call Forwarding:
To deactivate Call Forwarding:
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