Police fielded 250,697 calls on the line last year.
Masterton road police Senior Constable Harvey Pope said the *555 line was great for tip-offs about drunk drivers, boy racers and people behaving badly.
"We get a lot of tailgaters on the Rimutakas and people passing on double yellow lines. We've apprehended a lot of drunk drivers and driving that's not acceptable."
"If it's really bad people dial 111 but [*555] does get used quite a lot."
Giving drivers the opportunity to inform on one another helped deter dangerous behaviour on the roads, he said.
At the time *555 was brought in, New Zealand had only 65,000 cellphone users. The number of cellphones in use jumped to four million by 2006.
Calls range from traffic congestion to faulty traffic signals, drunk drivers, insecure loads and surface flooding.
Police communications operations manager Inspector Mal Schwartfeger said *555 calls were lower urgency than 111 calls.
"[*555] is a handy, short-dial system for members of the public to report non-urgent issues of concern about New Zealand roads and members of the public that drive on them who put other road users at risk."
Police can use the tip-offs to intervene, and have the power to prosecute if a witness is willing to make a statement. Fines can be issued on the spot if the driver admits the offence.
New Zealand Transport Agency (NZTA) road safety director Ernst Zollner said too many Kiwi families had their holidays marred by road tragedies.
"Drivers can do their part by planning ahead to share the driving and avoid fatigue, being patient and keeping to safe speeds, driving sober, avoiding distractions and checking their tyres, indicators and lights before heading off."
The 2012/13 Christmas holiday period saw six deaths, 70 serious injuries and 283 minor injuries - compared with 19 deaths the previous summer.
The official holiday period runs from 4pm on Christmas Eve until 6am on January 3.
The highest Christmas holiday road toll was in 1972/73 when 37 people died. APNZ
