40% of us suffer bill shock, with the $59 plan delivering the biggest shockers.

Aussies spend 50% more on phone bills than expected each month, new research out today has shown, with the popular $59 plan delivering the biggest bill shocks of all.

And it’s an expensive shock – costing Aussies an eye watering $557 million every year, according to research by Macquarie University with the support of amaysim, which examined over 200 mobile phone bills.

A massive 40% of phone users on contract suffer bill shock and signing up to a (seemingly) generous $129 or $60 plan leaves us just as exposed to bill shock as those who sign up for cheaper plans.

Read: Which Telco Is Bill-Shock King?

But the highest bill shock was incurred by those on $129 plans ($155.58 worth of a shock) followed by those on $59 plans ($34.58 shock), $60 plans ($24.40 shock) and $49 plans ($16.84 shock), on average.

‘Standard’ call charges (costing us $43.12), excess Internet data charges ($22.18) and international calls ($21.20) were the biggest causes of unexpectedly high mobile bills.

Excess data charges caused 43% of all occurrences of bill shock, the study called ‘The Anatomy of Bill Shock’, showed.

Dr David Gray, Senior Lecturer in Marketing from Macquarie University’s Faculty of Business and Economics faculty, said, “Recent changes adopted by the industry since this bill analysis are a step in the right direction, but the bills we’ve viewed even in the past few weeks still left us scratching our heads.”

“Despite a concerted effort to change the composition of the bill andadvertisements, it’s the concept of ‘included value’ in mobile plans that needs to be more clearly communicated to the consumer.

“This very big and real issue has still been left unaddressed by the industry,” he added.

There has also been warnings the new faster 4G LTE network may also cause a new round of bill shocks.

However, from next year telcos will be required by law to send user alerts no later than 48 hours after users hit thresholds of 50, 85 and 100 per cent on their plan, with some already doing so. 

The most popular mobile phone plans are the $59, $49 and $79 plans the study showed.

Females have a higher average incidence of bill shock and the 25-39 age group, followed by 40-49 are the biggest sufferers.

A total of 7 million phone users suffered bill shock last year.