If you are an O2 customer with a pay as you go SIM card lodged in your phone, you might soon notice two changes coming to your handset. Luckily they should both prove helpful.

As spotted by ISPreview and members of its forums, some customers of O2 (which is owned by Virgin Media O2) are beginning to notice their phones are becoming compatible with Wi-Fi Calling and 4G Calling, also known as VoLTE, which stands for Voice over LTE. LTE is another term for 4G network technology.

Both Wi-Fi calling and VoLTE are technologies that allow smartphones and other mobile phones to send and receive traditional voice calls over Wi-Fi and 4G respectively, as opposed to the older 2G network. Calls placed over Wi-Fi and 4G widely result in much better call quality when both participants of a call are using one of the technologies.

Though Wi-Fi Calling and 4G Calling have been available to O2’s pay monthly customers for some time, the modern features had been lacking for pay as you go customers.

O2 had previously confirmed the change was coming on an information page on its website, but the new reports from users seem to confirm the compatibility is now rolling out across the UK.

“4G & WiFi calling will be available for Pay As You Go customers by the end of 2025,” O2 said on its website. “To access it before then, you’ll need to switch to Pay Monthly.”

Virgin Media O2 did not respond to a request for comment from Express.co.uk.

The technologies will be welcome to O2’s pay as you go customers given the operator is shutting down its 3G network by the end of the year. It is the last UK operator to do so after EE, Vodafone and Three all completed this on their own networks. 3G was first introduced in the UK in 2003 but has been replaced with 4G and 5G networks with enough bandwidth to allow data-hungry services such as online gaming and video calling.

However, O2’s pay as you go customers could have still been relying on 3G to place voice calls, especially if they live in an area with patchy 2G signal. With the shutdown of 3G, relying solely on 2G for phone calls is now considered out of date.

Access to calls over Wi-Fi should mean a much more reliable and higher quality phone call experience. Calls are also increasingly more commonly placed over the 4G network by modern handsets to give better quality calls on the go, with the older 2G network there merely as backup.

If you are an O2 pay as you go customer with an iPhone or Android phone, you may need to toggle on Wi-Fi Calling or 4G Calling in your smartphone’s settings menu.