We are here to help you get answers to your questions about OneSimCard phones and services.
Are there any additional roaming charges?
There are NO additional roaming charges. The rates you see listed on our Rates & Coverage page are the only rates you will be charged when making or receiving calls on your OneSimCard enabled cell phone. This is true for using regular cellular voice or 1SIM VoIP App.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.
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 to activate and set up the mobile data service on your mobile device or tablet?
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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Will my order require a signature upon delivery?
Yes, please assume that your order will require a signature if it contains a cell phone.
The  eSIM World, eSIM Asiania, OneSimCard Europe & More and Universal SIM cards do not use the callback to make an outgoing call in over 70 countries.
Currently, the mobile application to remove the callback on other SIM cards is not available.
How should I send an SMSÂ to get charged only 15 cents per text message?
There are two ways for SMS message to be sent:
Bear in mind that sending SMS messages to the abbreviated special SMS destinations like voting, music downloads, etc. will cost you $9.00 per message.
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This does not apply to DataMax SIM cards.
How many times can I install an eSIM, and can it be installed on different devices?
For DataMax eSIMÂ can be installed once.How can I contact customer support?
There are a number of ways you can contact customer support.© 2006-2026 Belmont Telecom Inc., DBA OneSimCard.com. All rights reserved