How far should you stop behind the car in front?

At an intersection, set of traffic lights or in a queue of vehicles, how far should you stop behind the car in front?

There are two options:

Park far enough behind so that you can see the tyres of the vehicle in front
Park reasonably close.

Let’s look at each one.

Stopping leaving a decent gap

You have a better view of the road ahead, especially if the vehicle in front is a truck or bus
If the vehicle in front stalls or breaks down then you can easily get around them without having to reverse
If another vehicle hits you from behind you are less likely to hit the vehicle in front
Less fumes will enter your vehicle or helmet – this is good if it’s an old diesel-powered vehicle ahead which is likely to create more fumes
As you are preparing to stop earlier, it gives you more margin for error, which is particularly useful on a motorbike when you might need to avoid a slippery patch on the road
If you stop facing uphill the vehicle in front might roll back slightly which could cause a minor crash
Leaving a gap allows pedestrians to walk through safely
Leaving a gap allows motorbikes and cyclists to filter more safely as it gives them a space to stop. They will get to their destination before you anyway, so there’s no point in deliberately preventing them from doing this
If you notice someone behind might not stop, you can move forward to give them more space

Stopping close to the vehicle in front

Allows more vehicles to fit in that stretch of road, which minimises the impact of rush hour congestion
Modern vehicles are much less likely to stall or break down, so that’s not a risk
You can close your air vents if the vehicle ahead produces a lot of exhaust fumes.

As you can see in this diagram, there are two lanes of traffic that have stopped at a pedestrian crossing. The left lane fits 6 vehicles in, while the right lane fits only 5.

Which one should you use?

If heavy traffic is moving slowly and consistently, and the road is not uphill, stopping close to the vehicle in front poses little risk; leaving a lot of room between you and the vehicle in front means that less vehicles can fit in that stretch of road, and that prolongs rush hour. However, if you are approaching a T intersection, traffic lights or a pedestrian crossing and traffic is light, try to leave enough gap to see where the tyres touch the tarmac in the vehicle ahead.