What is the social cost of a car crash?

In a vehicle crash the obvious cost is the damage to the vehicle but there is a social cost, too, as many other people are affected by the crash. The Ministry of Transport publishes social cost figures every year.

New drivers are at the most risk of crashing and they have the most potential value over their lifetime.

Here are the key highlights from the spreadsheet, based on June 2024 prices using 2021–2023 crash data:

Cost per fatality: $14,983,800 (roughly $15 million): This breaks down as: the value of the life lost ($14.93 million), medical costs ($8,600), legal and court costs ($35,300), and vehicle damage ($9,000). The human cost (the loss of life component) dwarfs everything else.

Cost per serious injury: $808,400 (all roads): On a reported injury basis, this rises to $1,511,000 — because not all serious injuries are reported, so the figure is scaled up to account for the real-world total. The bulk of this is the permanent disability component ($776,400), with medical costs adding $19,000 on top.

Cost per minor injury: $91,500 (all roads): On a reported injury basis: $280,200. Again, the scaling reflects the fact that many minor injuries never make it into the official crash data.

The total social cost of road crashes in New Zealand runs to roughly $13–16 billion per year across the dataset, with fatalities consistently accounting for the largest share; often more than serious and minor injuries combined.

Rural crashes cost significantly more than urban ones. A fatal crash in a rural area carries an average cost of around $18 million, compared to roughly $16.3 million in urban areas, reflecting higher severity outcomes on open roads.

The most expensive crash type by movement is head-on collisions (not overtaking) at $3.25 million per incident.

Why are the social costs so high?

The costs are high because they contain five elements:

Loss of life and life quality

When a life is lost, it cannot be productive, and therefore, there is a cost. That person would have worked for a number of years, and the value now can’t be realised.

When life quality is lost, e.g. a person is permanently disabled, their enjoyment of life is affected, and they are not as productive in the long term.

Loss of output due to temporary incapacitation

If a person is temporarily incapacitated, they will be unable to contribute productively to society. They may need retraining (often supplied by the government)

Medical costs

Hospitals and medical care are paid for by the government unless the person has private health insurance. Ambulances and other emergency services might attend the accident. Trauma counselling may be required.

Legal costs

Police and crash investigators must find out the cause of the accident and who is at fault. This can involve a number of investigative agencies. Prosecutions by the crown may be brought against the person at fault. Any fines must be followed up, as will insurance claims. If a driver goes to prison, those costs are borne by the government.

For example, if the fatality was caused by road rage, then the investigation and prosecution could be expensive. The person who caused it will go through the court system and may end up in jail.

Property damage costs

In serious crashes there can be damage to road infrastructure such as the road surface, power poles, fences and traffic lights. Private property might also be damaged. Vehicles may need to be towed away. There may be health costs for local air pollution.

There is also the cost to other people – loss of business and increase in fuel use due to road delays, loss of time to people who stop and render first aid, for example.

The total social cost of road accidents

The total amount is around $4.45 billion per year. 91% of this is social cost, 5% vehicle cost and other costs are 4%.