How to find the right APN settings for your carrier
Thomas Rutter

In order to use cellular data on a device with a SIM card (using the cellular network, as opposed to a local Wi-Fi network), your device needs to know the correct APN (Access Point Names) settings to use.

When you need APN settings

In almost all normal situations where you buy or obtain a smartphone, it will already have APN settings for your chosen provider already. You will normally not have to input any APN configuration.

There are various mechanisms whereby your smartphone may automatically get APN settings for your carrier:

Pre-installed on the device

Android phones come pre-installed with a large database of APN configurations for many different carriers around the world. You probably won't be able to view them all in the APN settings, since the settings screen only shows APN configurations for your current network, based on the MCC and MNC fields provided by the network.

Pushed to your device by the network

Often, simply inserting a SIM card from your provider is enough. Upon seeing your device for the first time, the network will push (via SMS) some configuration options to your device.

When you need to set up an APN configuration manually

In rare cases where you cannot already use mobile data out of the box, the best option is often to conduct a Google search for your provider's APN settings.

For example if your carrier is "Telstra", search Google for the terms Telstra APN settings and you may find what you're after. Try looking in the search results for something official-looking from the company first, but if that fails there are often many Google results that lead to people who have compiled and collected relevant APN settings themselves.

Alternatively, you can also contact the customer support for your carrier. Good luck.

Keep in mind that many (but not all) carriers require separate APN settings for Internet data and MMS, and some might require different APN settings depending on other details such as:

What type of contract or plan you are using
What type of device you are using

Other carriers will be very much "one size fits all", allowing you to simply use the same settings no matter who you are or what you're doing.