We are here to help you get answers to your questions about OneSimCard phones and services.
I used a large amount of data  even though I barely used data, what happened?
Each mobile data session is charged for a minimum of 10kB usage. Even if you check just one 3k email you will be charged for 10kB of usage. In some countries this can be over 30¢ per session, however in Europe and elsewhere it can be as little as 1¢. Check all rates.
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Each mobile data session is charged for a minimum of 100kB usage. Even if you check just one 3k email you will be charged for 100kB of usage.
Please note: Some phones, like iPhones, Androids, and other smartphones, can access data without you even knowing it if you have data enabled. We strongly recommend checking the settings on your phone and disable mobile data roaming if you will not be needing data service. By default, all SIM cards are pre-programmed with data service enabled, once you activate your data package.
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Can I get rewarded for referring friends to OneSimCard?
Yes, you can! Our Refer a Friend program is available to all OneSimCard active account holders. For each friend you refer that purchases new service, you will receive $10 ($5 for rentals) deposited into your 1SIM Money Fund. The referral bonus will be received once the order for new service is placed, shipped and the 30-day return window has closed. You can then use these bonus awards to recharge your airtime or use toward any other purchases. There are no limits to the number of friends you can refer or the bonuses you can receive!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.
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 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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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.How do I prevent the service from expiring?
The OneSimCard phone number has no expiration, provided you made at least 1 call or sent an SMS once every 12 months.
However, the funds on the SIM expire 10 months after your last recharge. The minimum recharge amount is $25. You can keep the balance from expiring by simply recharging at least once every 10 months. If you let your balance expire, then all you need to do to get the service up and running again is to log in and add funds to your SIM card. Automatic recharge will be canceled if you let your funds expire.
NOTE: For Physical 3-in-1Â DataMax & DataMax eSIM SIM cards, if the SIM card has no balance, the SIM will expire and be removed from the account after 7 days, unless there is a data package currently active on the SIM (not a future activation). If there is no balance on the SIM and the active data package expires, the SIM will expire 7 days following the expiration of the active data package.
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An expired SIM can be restored for a $10.00 restoration fee plus a recharge of at least $25.00.
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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.
How can I contact customer support?
There are a number of ways you can contact customer support.Can I be notified of missed calls when my phone is off or outside of a coverage area?
Yes, for Universal, Expedition, and eSIM World Sim Cards, you will receive SMS or email notifications when you miss a call due to your phone being off or out of coverage. SMS notifications are sent when the phone is unavailable for a period up to 4 hours. Email notifications are sent, regardless of the time period, to the email address you have entered into your online voicemail profile. Notifications will be sent when you make/receive a call or enter a new roaming country. NOTE: if the caller leaves a voicemail message then you will not receive this extra missed call notification.
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