There are 590 emergency telephones on Melbourne's freeway network, but VicRoads says they are rarely used these days because most people have mobile phones.

An evaluation of the phones' use and maintenance costs found the phones are used so infrequently these days that each call cost an average $1000. The total cost of maintaining the phones is about $370,000.

Help phones on the Eastern Freeway were each used less than once a year on average last year, VicRoads said.

The phones must be upgraded to next-generation technology next year at a cost of $320,000, so VicRoads has launched a public review of their demand and may discontinue the safety service instead, if it gains public approval to do so.

In a statement, VicRoads chief executive John Merritt said the authority recommends people use their mobile phones in a breakdown, in preference to the roadside phones, as it is safer to stay inside the vehicle.

"If you break down on any freeway we recommend that people stay in their vehicle and use their mobile phone to call for assistance," Mr Merritt said.

He said CCTV cameras and freeway data stations were also in place to detect crashes, breakdowns and hazards such as debris on the roads, and often did so before anybody made a call to report a problem.

"VicRoads has extensive monitoring systems in place on our freeway network that assist us to detect and respond to freeway incidents," Mr Merritt said.

The help phones have been part of Melbourne's freeway landscape since the 1970s and have a direct line to VicRoads' traffic management centre.

VicRoads said almost 200 help phones would remain in place on outer suburban areas, where electronic monitoring is limited, and on rural freeways. Phones in toll road tunnels on CityLink and EastLink will also stay.

Brian Negus, general manager of public policy for the RACV, backed VicRoads' decision to review the phones and encouraged motorists to contribute via an online survey.

"It's a good idea to gather the facts about the use of freeway phones both in metropolitan Melbourne and in regional Victoria, so that we can look at their effectiveness and whether other alternatives are more appropriate," Mr Negus said.