Staying connected while traveling no longer needs to involve swapping tiny SIM cards or visiting local carrier stores.
With eSIM technology, your Galaxy S21 Ultra 5G can activate a mobile plan digitally in just a few minutes.
Whether you're preparing for an international trip or setting up mobile data before arrival, installing an iRoamly eSIM is a fast and convenient solution.
This guide will walk you through the complete setup process on the Samsung Galaxy S21 Ultra 5G, including QR code installation, manual activation, and how to confirm everything is working correctly.
Preparations Before Setting Up iRomly eSIM
Before starting the installation process, make sure you have the following ready:
A stable internet connection (Wi-Fi is recommended)
A valid eSIM QR code or activation code provided by your carrier
Your Galaxy S21 Ultra 5G powered on and unlocked
The device updated to the latest available One UI version for better eSIM compatibility
The carrier account activated and eligible for eSIM service
Method 1: Install eSIM Using a QR Code
Step 1: Open SIM Card Manager
Open Settings.
Tap Connections.
Tap SIM card manager.
This menu manages both physical SIM cards and eSIM profiles.
Step 2: Start Adding an eSIM
In SIM card manager, tap Add mobile plan.
Wait while the phone searches for available plans.
If no automatic plan is found, proceed to the QR scanning option.
Step 3: Select the QR Code Option
Tap Scan carrier QR code.
The camera scanner screen will open automatically.
Step 4: Scan the Carrier QR Code
Hold the QR code in front of the camera.
Keep the QR code centered inside the scanning frame.
Wait for the phone to recognize the code.
Once detected, the device displays the carrier profile information.
Step 5: Download the eSIM Profile
Tap Add or Download when prompted.
Wait while the Galaxy S21 Ultra downloads the eSIM configuration from the carrier.
This process may take several minutes.
Do not:
Close the Settings app
Turn off the phone
Disconnect from Wi-Fi
Step 6: Activate the eSIM
After the download completes, tap Settings if prompted.
Return to Settings → Connections → SIM card manager.
Locate the newly installed eSIM.
Toggle the switch next to the eSIM to On.
The eSIM is now active.
Method 2: Install eSIM Using Manual Input
Step 1: Open SIM Card Manager
Open Settings.
Tap Connections.
Tap SIM card manager.
Step 2: Start eSIM Setup
Tap Add mobile plan.
Wait for the search process to finish.
Step 3: Open Manual Entry
Tap Scan carrier QR code.
On the QR scanner screen, tap Enter activation code.
Some One UI versions may display:
Enter code manually
Need help?
Manual activation
Select the manual entry option displayed on your device.
Step 4: Enter the Activation Code
Tap the Activation code field.
Enter the activation code provided by your carrier.
Tap Connect.
Step 5: Download and Install the eSIM
Wait while the Galaxy phone connects to the carrier server.
The device will automatically download and install the eSIM profile.
The installation process may take several minutes.
Step 6: Enable the eSIM
Return to Settings → Connections → SIM card manager.
Locate the installed eSIM profile.
Toggle the eSIM switch to On.
The eSIM is now activated.
How to Confirm the eSIM Was Installed Successfully
Check SIM Status
Open Settings.
Tap Connections.
Tap SIM card manager.
You should now see:
The carrier name
An active eSIM toggle
Signal bars for the eSIM network
Check Mobile Network Connectivity
Swipe down from the top of the screen.
Verify that mobile signal bars appear.
Look for:
4G
LTE
5G
near the signal indicator.
Test Calling and Data
Perform the following tests:
Open the Phone app.
Make a test call.
Note: Some eSIM plans may not include voice calling support, so this feature might not be available depending on your plan.
Then:
Open a web browser.
Disable Wi-Fi temporarily.
Confirm mobile data works correctly.
Conclusion
Now that your iRoamly eSIM is installed on the Galaxy S21 Ultra 5G, you can enjoy the convenience of digital mobile activation without needing a physical SIM card.
The setup process only takes a few minutes, and Samsung’s eSIM support makes managing mobile plans simple and flexible. If needed, you can always return to the SIM card manager to adjust settings or manage additional eSIM profiles later.