Curb extensions (sometimes called curb bumpouts, neckdowns or bulbouts) are a [[traffic-calming]] intervention at street crossings, deployed to increase intersection safety.
By shrinking the width of a street at its crossing, bumpouts decrease the street crossing distance, increase pedestrian visibility and driver awareness at the crossing, prevent high-speed turning or through traffic at the crossing, and assure street users that crossing the street is an intended use of the location.
The most effective type of bumpout is a permanent extension of the curb, but paint, or alternative materials such as jersey barriers, bollards, or planters, function as quick impermanent solutions.