Setup
How to activate an eSIM: from installed profile to working internet
Activate an installed eSIM by turning on the line, selecting it for mobile data, and configuring roaming correctly. Includes checks for iPhone and Android.
In this guide
An eSIM is active for internet when the profile is turned on, selected as the mobile-data line, and connected to a permitted network. With a travel eSIM, data roaming usually needs to be enabled. Installation only downloads the profile; activation is the step that actually puts the line into use.
HolySim advice: check your order email to see when the validity starts. It may begin at installation, on a fixed date, or at the first network connection.
First determine whether the eSIM is already installed
Open your phone’s SIM manager. On iPhone, this is under Settings > Cellular. Samsung uses Settings > Connections > SIM manager. On a Google Pixel, go to Settings > Network & internet > SIMs.
If the new line appears in the list, do not scan the QR code again. Give it a recognizable label and continue with the activation settings. If the profile is missing, use the installation instructions for your device. The complete steps are already available for Samsung Galaxy and Google Pixel.
Turn on the line
Tap the eSIM profile and enable the line. On iPhone, this is usually called Turn On This Line. Pixel uses Use SIM. Samsung shows a switch beside the eSIM in SIM manager.
The phone may briefly search for a network. If you are still outside the plan’s coverage area, a network name does not have to appear. A regional travel eSIM for Asia, for example, may not fully register while you are still at home in the Netherlands.
Select the eSIM for mobile data
A phone can have several SIMs enabled, but normally uses one line at a time for mobile data. Select the HolySim eSIM as the data line:
- on iPhone through Settings > Cellular > Cellular Data;
- on Samsung through Settings > Connections > SIM manager > Mobile data;
- on Pixel through Settings > Network & internet > SIMs > Mobile data.
Keep your regular SIM active for calls and SMS if you want to remain reachable on your own number. A data-only eSIM does not take over your WhatsApp account or change your existing number.
Turn off automatic mobile data switching if you want to prevent the phone from using the regular SIM when eSIM coverage is weak. On iPhone, this setting may be called Allow Cellular Data Switching. Android manufacturers use different names.
Turn on data roaming
A travel eSIM often connects through a local partner network. Data roaming therefore usually needs to be enabled on the travel eSIM. Open the settings for that specific profile and turn on Data Roaming.
Then check the regular SIM. If the country is not included in your home plan, leave data roaming off there. This distinction matters more than only looking at a general roaming switch.
Network selection and APN
Leave network selection on automatic at first. The eSIM then chooses a partner permitted by the plan. Only select a network manually when the order details list several supported networks or HolySim support advises it.
Do not change the APN in advance. Many profiles supply the correct setting automatically. If you see reception and a data icon but nothing loads, compare the APN with the plan instructions before changing it.
Test activation
Turn off Wi-Fi. Open a new page and check whether 4G, LTE, or 5G is visible. If in doubt, follow this order:
- Confirm that the eSIM line is on.
- Confirm that mobile data is assigned to that line.
- Check roaming on the travel eSIM.
- Turn Airplane Mode on for ten seconds and off again.
- Restart the phone.
- Test outdoors or near a window.
Do not delete the profile. A network issue is not solved by undoing a potentially one-time installation.
Match the error to the next check
If the system status remains literally on Activating, keep the profile installed and collect a screenshot of the SIM manager. If you see No service, Searching, or SOS only, first verify the coverage area, selected line, and automatic network selection. If there is reception but no data traffic, check roaming and APN.
Take screenshots of SIM manager, the selected data line, and the error message before contacting support. Hide the QR code and full activation code.
Sources and editorial review
The general activation process was checked against documentation from Apple, Samsung, and Google Pixel. Menu names and carrier features change between software versions. Content last reviewed on July 15, 2026.
Frequently asked questions
Is installing the same as activating?
No. Installation downloads the profile. Activation means that the line is on and connects to a network for calls or data.
When does my HolySim plan start?
That is listed with the plan. Check whether the validity starts at installation, on a fixed date, or at the first network connection.
Does roaming need to be enabled?
Usually, yes, for a travel eSIM. Only enable it on the travel eSIM and check the regular SIM separately.
Why does the eSIM not work at home yet?
A destination-specific profile may only register on a supported network in the valid country or region.
How can I be sure mobile data uses the eSIM?
Explicitly select the eSIM as the data line, turn off Wi-Fi, and load a new web page. Then check usage by SIM if your phone displays it.
