From Monday it will be illegal for children under seven years old to be strapped solely in a seatbelt.

The new Victorian rules also cover mobile phones, parking, crossing single lines, motorcyclists, cyclists and pedestrians.

RACV chief engineer of traffic and transport, Peter Daly, said the rules upgrade removed some grey areas that had allowed road users to "get away with dangerous behaviour".

"These rules... clarify mobile phone use including drivers not being able to text a message on their phone, read or send emails," Mr Daly said.

"Parents who prematurely put their children in an adult seatbelt are taking a great risk as research has found that children up to seven years old are at least four times more likely to sustain a head injury in a crash when sitting in an adult seatbelt.

"By putting your child in an appropriate restraint you are reducing that risk of death or serious injury to your child by a significant 70 per cent."

Insurer AAMI predicted the new mobile phone rules would have the biggest impact based on a survey that showed one in two Victorian drivers admit to using their phone for calls or texting without using a hands-free kit.

According to AAMI's corporate affairs manager, Yves Noldus, about 1.5 million Victorians would risk breaking the law after November 9 unless they learned to resist the temptation of texting while behind the wheel.

The new rules also cover GPS and other visual display devices which must be secured in a holder fixed to the vehicle.

Drivers cannot cross a continuous white dividing line unless turning from or onto the road, pedestrians walking on a road must face the traffic direction and motorcycle pillion passengers must be aged over eight.

A full list of the new rules is on the VicRoads website.