The upcoming switch off of the Telstra 3G Network has the potential to leave 750,000 people stranded in the event of an emergency with handsets not capable of “VoLTE” unable to make triple-zero calls. For those on the Telstra network, there’s a simple tool to find out if you’ll be ok.

Thanks to EFTM Man Cave member Peter, we’ve learned of Telstra’s 3498 SMS number.

It’s quite simple – you text the number 3 to 3498 as a Telstra customer, you’ll receive a response that tells you if your phone is compatible with the VoLTE network on 4G.

Testing by other EFTM readers shows that this also works for Belong customers, and Boost Mobile customers – likely because those are subsets of the Telstra network, not independent MVNOs. Aldi Mobile customers report it does not work for them.

For what it’s worth, EFTM reached out to Optus to see if they had a similar compatibility tool – seems they don’t, as an Optus Spokesperson said “Optus is communicating directly with customers through a range of channels who may be impacted by our 3G shutdown.

In our communication, we specify which of the customer’s devices may be impacted and how to get further information and assistance to upgrade their device.

“Impacted devices may include not only handsets but also data-only devices, e.g., tablets and dongles.”

The learning here is – check. And don’t ignore messages from your Telco about 3G shutdown.