Telstra and Optus have pushed back the closure of their 3G networks to 28 October to make "one last" public awareness push before they pull the plug.

In a joint release on Wednesday 14 August, the telcos said they will invest in a "public safety campaign" to ensure Australians still depending on the older network to know how to switch to 4G and 5G.

The telcos say the closure is necessary to free spectrum for the newer networks, which are faster than 3G.

“We have been communicating to customers about the need to prepare and make the move for almost five years. This has included multiple letters, bill messages, SMS, public awareness campaigns, advertising – even door knocking and sending free phones to people in vulnerable circumstances, and our support for customers won’t end the day the network closes,” Telstra CEO Vicki Brady said.

Telstra had already extended its shutdown date from 31 June this year to 31 August, while Optus had planned to began its shutdown from September.

Telstra and Optus customers can check where their respective coverage maps online to see if their area should be covered under the 3G, 4G and 5G networks.

Telstra customers can also text '3'to '3498' to check if their phone is 4G-compatible.

Warren, like many Western Plains shire centres, is covered by 4G and 5G. PHOTO: River McCrossen

Warren Motor Inn manager Gwyn Davis said his business is already prepared for the end of 3G, although he's concerned that guests may not be.

"We always have a lot of problems with people getting reception for booking accommodation," Gwyn said, also a member of the local Chamber of Commerce.

"I'm a bit sceptical that it's going to be a bit of a problem for when the 4G actually comes in."

 The Warren township is currently covered by Telstra and Optus according to their coverage maps.

Gwyn said the deadline should be pushed further than October, although he did not give a precise date.

"I would like to see it extended as long as people have the opportunity for their sets to actually be replaced at no charge, irrespective of their income," he said.

National Farmers Federation President David Jochinke welcomed the move, although he warned people not to leave the switch to the last minute.

“This is not the time to take a ‘she’ll be right’ attitude. I urge people to check their devices urgently and make sure they are compatible with the 4G and 5G networks,” Mr Jochinke said.

“If you don’t know whether your device runs on the 3G network, you must contact the manufacturer to find out. Make sure this is on the top of your priority list.

“We can’t keep prolonging the inevitable. Let’s use this time wisely and then start focusing on how we move forward and address the systemic issues facing rural connectivity.”

The delay announcement comes after telco representatives fronting a federal parliamentary hearing in July faced concerns the 4G and 5G footprints won't match the current 3G service area.

READ MORE: Telstra front inquiry ahead of 3G closure