Drivers who fail to indicate at roundabouts or stop for pedestrians at crossings will soon face big fines if they're caught.

Land Transport New Zealand is toughening up the way some road rules are policed in a bid to reduce fatal crashes. Every year 250 people are injured and three die on roundabouts. And in a bid to make them safer, failing to indicate is to become illegal.

Andy Knackstedt from Land Transport NZ says failing to indicate causes confusion. "When people fail to indicate...other drivers don't know what they're doing, it can cause crashes."

From the end of the month, if people don't indicate and get caught they will receive a $150 fine.

Under the rules a driver must indicate if turning left or right at a roundabout, but when wanting to exit the roundabout drivers must signal which exit they will take. If going straight ahead, there's no need to indicate but drivers must indicate as they leave the roundabout.

Knackstedt says it has been a long-standing rule in the road code, but most people don't do it.

On average three pedestrians are killed at crossings each year and over 100 are injured. So tough new laws will also apply at pedestrian crossings. Drivers must give way to pedestrians on both sides of a crossing unless the crossing is divided by a raised traffic island. The penalty for not complying is another $150 fine.

The new rules come into force on February 27.