How to drive in a roundabout: rules and best practices

A roundabout is a circular intersection designed to improve traffic flow and safety by forcing drivers to move in one direction around a central island. Unlike traditional intersections controlled by traffic signals or stop signs, modern roundabouts rely on continuous movement, which the Federal Highway Administration reports can reduce fatal accidents by up to 90% compared to stop-controlled intersections.

Despite their safety benefits, many drivers find the transition from traditional intersections to roundabouts disorienting. By following standardized traffic protocols, you can navigate these structures efficiently without disrupting the flow of other vehicles.

Who has the right of way in a roundabout?

Drivers already circulating inside the roundabout always have the right of way. When you approach a roundabout, you must slow down and yield to traffic currently within the circle. You should not enter the roundabout until there is a sufficient gap in traffic that allows you to merge safely without forcing other drivers to brake or change speed.

To navigate this correctly:

1. Observe the yield signs and pavement markings as you approach the entrance.
2. Slow your vehicle to a speed that allows you to stop if necessary.
3. Look to your left to monitor oncoming traffic already in the circle.
4. Merge into the circle only when a safe opening appears.
5. Do not come to a complete stop if the way is clear, as this can cause rear-end collisions.

According to the Federal Highway Administration, yield-at-entry is the primary mechanism that prevents gridlock and ensures that the intersection functions as intended. If you are already inside the roundabout, you have the priority, but you should remain vigilant for vehicles entering the circle, as not every driver will perfectly time their entry.

When should you use your turn signal?

In most jurisdictions, you should use your right turn signal immediately before you exit the roundabout. While signaling requirements vary slightly by state, the general rule is to treat the roundabout like any other road: signal your intention to leave the lane you are currently occupying. Signaling helps drivers waiting at the entrance understand your path, which allows them to enter the circle more safely.

Follow these steps for proper signaling:

1. Maintain your course within the roundabout as you pass the exits preceding your intended one.
2. Activate your right turn signal as you approach the exit you plan to take.
3. Complete your exit and turn off your signal once you have merged into the lane on the exiting road.

Avoid using a left turn signal while inside the roundabout unless your specific state laws mandate it for navigation. In many cases, a left signal can confuse other drivers who may mistake your intent, potentially leading to unnecessary hesitation or dangerous maneuvers.

How do you navigate a multilane roundabout?

Navigating a multilane roundabout requires choosing your lane before you reach the entrance based on the destination you intend to reach. Pavement markings and roadside signage are designed to guide you into the correct lane for specific turns. Once you are in a lane, you must commit to it until you exit; changing lanes while inside the roundabout is dangerous and often prohibited by local traffic ordinances.

To safely navigate multiple lanes:

1. Identify your exit before entering the roundabout by observing overhead signs.
2. Position your vehicle in the designated lane as indicated by the arrows on the road.
3. Remain in your lane throughout the entire circle, following the path marked for your direction.
4. Exit the roundabout from the same lane you entered in, unless signs indicate otherwise.

Cutting across lanes to reach an exit is a common cause of accidents in multilane roundabouts. If you find yourself in the wrong lane, do not attempt to force your way over. Instead, continue around the circle until you can safely exit and find a legal way to turn around or reroute.

What are the rules for large vehicles and trucks?

Large vehicles, such as semi-trucks or vehicles towing trailers, often require more space than a standard passenger car can provide. Many modern roundabouts feature a "truck apron," which is a raised, paved area around the central island designed specifically for the rear wheels of long vehicles to track over while the front wheels stay on the main roadway.

If you are driving a large vehicle:

1. Approach the roundabout cautiously and ensure you have enough room to maneuver.
2. Utilize the truck apron if your vehicle's turning radius makes it necessary.
3. Be aware that your vehicle may take up both lanes if you are in a multilane roundabout.

If you are driving a passenger car near a large vehicle, give them extra space. Do not attempt to pull alongside a truck inside a roundabout, as they may need to swing wide to navigate the curve. Staying behind or well ahead of large vehicles prevents you from entering their blind spots or getting caught in their path of travel.

What should you never do in a roundabout?

Certain behaviors within a roundabout are universally discouraged because they disrupt traffic flow and increase the risk of collisions. Most importantly, you should never stop inside the roundabout to let someone else in; the vehicles already in the circle have the right of way, and stopping forces an unexpected hazard for drivers behind you.

Other critical "don'ts" include:

• Never drive across the center island, even if you are in a small vehicle.