We are here to help you get answers to your questions about OneSimCard phones and services.
Will a OneSimCard international SIM card work with my mobile phone?
OneSimCard will work with almost any unlocked GSM tri-band or quad-band cell phone. A partial list of compatible cell phones that we have tested can be viewed here.
If you need to unlock the phone, we suggest contacting your carrier or phone manufacturer for unlocking information or services.
If your phone is not a quad-band phone, please make sure that the bands of your phone are those required in the country of your travel. You can look it up here.
If you are still unsure whether your cell phone is compatible, contact support or purchase an international cell phone and SIM card bundle from us, which all come preloaded with our international SIM card, $10 balance and OneSimCard Apps Installed.
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.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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What is the cost of calling between two OneSim VoIP phones?
Calls between two OneSim VoIP phones are absolutely free.Do I need to have a OneSimCard SIM card installed in my phone to use OneSim VoIP?
No. OneSimCard SIM is not required to be installed in the phone for OneSim VoIP to be used. However, you do need to have OneSimCard account with a VoIP capable PEN.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:
How can I dial '+' on my phone when making call?
Note: You can always dial 00 instead of + when making outgoing calls. For example, to reach OneSimCard customer service in the USA you can just dial 001 617 3138888.
You should consult the phone manual for this info. Different manufacturers have specific ways to access the '+' key, so make sure you know yours.
Here are few known ways:
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Do I need to have Data Roaming turned on for eSIM to work?
Yes. Data Roaming should be enabled on your phone for eSIM for data to work. Calls and texts on eSIM World should work with or without it.
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.
How do I recharge using 1SIM Fund?
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