We are here to help you get answers to your questions about OneSimCard phones and services.
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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How do I top up my data with eSIM?
There are two ways you can do this:
Simply go onto your web account or eSIM app and purchase a new data package appropriate to your travel needs.
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.
What is time validity of OneSimCard SIM?
All SIM types are valid for 1 year after the last billable use - phone call, sent SMS or data use.
The SIM balance for all types of OneSimCard SIMs is valid for 10 months after the last recharge. Each recharge extends the balance for the next 10 months period. If you do not recharge within the 10-month period, any remaining balance will be forfeited.
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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. Additionally, if a data package is purchased, and set for future activation, the inactive data package will expire after 6 months from the date of purchase.
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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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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.
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.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.How often do I need to recharge my OneSimCard account?
For Universal E, Expedition E, eSIM World E, eSIM Asiania, Plus, Europe & More, & Standard SIM Cards, the international SIM card phone number and account will expire if no outgoing usage is made for 12 months. The outgoing usage could be any of the following: Call made from the phone, SMS sent from the phone or any Data Usage.
Personal Extra Numbers will stay active as long as they have been funded properly.
The SIM card balance is valid for 10 months. The balance will continuously roll over to the next 10 month period provided that at least $25 is added within 10 months after the last recharge.
If the balance expires, the service can still be used after a new recharge of the SIM card.
For Physical 3-in-1Â DataMax & DataMax eSIM SIM Cards, the SIM card and account will expire if no outgoing usage is made for 12 months. The outgoing usage could be any of the following: Call made from the OneSIM VoIP App, SMS sent from the OneSim VoIP app or any Data Usage.
Personal Extra Numbers will stay active as long as they have been funded properly and the SIM hasn’t expired. If the SIM card expires, but then is restored ($10 Restoration Fee applies), the PEN will be re-attached to the SIM card, as long as the PEN hasn’t expired based on the time period for which the PEN was purchased.
The SIM card balance is valid for 10 months. The balance will continuously roll over to the next 10-month period provided that at least $25 is added within 10 months after the last recharge.
If the SIM card balance expires, 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. So, to keep the SIM active you need to either keep a balance on the SIM or an active data package.Â
NOTE:Â If there is balance on the SIM card, but no data is used for 15 consecutive days, the SIM card will be blocked/suspended. To unblock the SIM card, simply go to your account portal and in the "My SIM cards" tab, click on "Unblock" on the "SIM Type" line.
An expired SIM can be restored for a $10.00 restoration fee plus a recharge of at least $25.00.
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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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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.
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