New data from Telstra and YouGov shows that over half of Australians can't remember a single mobile or landline number by heart especially in an emergency situation.

Memory expert Anastasia Woolmer said this "number recall crisis" was a growing problem.

"This is concerning, but not surprising actually, given what I've learned with a lot of students struggling to remember basic information like numbers," she said.

"Many of us rely on our smartphones to store contacts."

As phones become more advanced and the process of calling people becomes more automated, Australians aren't memorising numbers in the way they used to.

In the survey, 47 per cent said if they found themselves in an emergency situation without their smartphone they wouldn't know what to do.

Ms Woolmer is now encouraging Australians to commit to remembering a useful phone number in case of an emergency.

"Most of Australians, 78 per cent of us, want to be able to remember phone numbers better," she said.

Using the "chop, swap, don't stop" technique Australians can break down a number into smaller, more memorable blocks.

Ms Woolmer says Australians should "chop" the 04 before mobile numbers leaving only eight numbers to remember split into three chunks.

For the remaining numbers "swap" the number with a word based of the corresponding letters on the keypad to create a short phrase.

Ms Woolmer then said "don't stop". Australians should repeat the number phrase every time they see a particular object such as a payphone to commit it to memory.