We are here to help you get answers to your questions about OneSimCard phones and services.
How do I install my eSIM?
Before purchasing, please ensure you have verified that your device is unlocked and one of the supported devices. Installation is completed by using your phone to scan the QR code of the purchased eSIM. You may scan the QR code by displaying it on the computer screen, another device, or a printed copy.
If you’ve already purchased OneSimCard eSIM, you can see full installation instructions and access your QR code from the Recharge menu in your online account. Make sure eSIM is selected in the Select SIM Card drop down menu.
If you have not purchased your eSIM yet, learn more about international eSIM here.
How does eSIM works?
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:
1. For Standard and Plus OneSimCard SIM: +3725099000 for all countries except:
a. China: +85290296747
2. For the Expedition (former Data & Roam) SIM as well as for Europe & More SIM: +37256100041
Special instructions for Apple Phones:
With Apple iPhones to check SMSC:
From the phone dialer Dial *#5005*7672#
You will see the SMSC set currently on the phone.
To change the SMSC on Iphone dial:
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: **5005*7672*+37256100041#
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
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:
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.
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.
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.
Do I need to change any settings on my phone when going abroad?
Not Really. If you are planning to use Mobile Data, you will need to enable Data Roaming on your phone. Everything else in modern phones get done automatically. However, you should ensure that the APN on the device is correctly updated when the SIM card or eSIM card is enabled.Universal, Expedition, & eSIM World SIM card types:
Name: 1SIM
APN: send.ee
Leave all other settings alone
DataMax, DataMax eSIM, & IoT Track SIM card types
Name: 1SIM (NOTE: Most IoT devices do NOT have a setting/field for “Name”)
APN : OSC (NOTE: The “O” is the LETTER O, NOT the number 0)
Leave all other settings alone
I can make calls through OneSim VoIP. However incoming calls are going through my roaming SIM. What's wrong?
If your incoming calls are not being routed through the OneSim VoIP app then you are either not connected to Wi-Fi or the OneSim VoIP app is not active.Which phone number will be shown on the caller ID when I make a call using OneSim VoIP?
Your active OneSim VoIP Personal Extra Number (PEN) will be shown on the caller ID.How does OneSim VoIP work when the call is received?
When someone dials your OneSim VoIP enabled Personal Extra Number (PEN), the system will first check if your OneSimCard phone is registered with the OneSim VoIP app on a Wi-Fi network. If it is registered, the call will be sent using VoIP. If the OneSim VoIP app is not running or it is not registered on a Wi-Fi network, then the call will be sent using the standard OneSimCard roaming network and charged our standard roaming rates.© 2006-2025 Belmont Telecom Inc., DBA OneSimCard.com. All rights reserved