Vehicle Controls and Ergonomics
Increasing Speed Smoothly and Appropriately
Last reviewed: 2026 · Driviology Road Safety Education Team
Quick Answer
Increasing speed appropriately - such as when merging onto a highway - means accelerating smoothly and early enough to match traffic flow, distinct from the legal issue of speeding beyond the posted limit.
Increasing speed is sometimes a necessary, legitimate technique, not automatically the same issue as speeding.
When Increasing Speed Is the Right Call
Merging onto a highway or safely completing an overtake both call for a deliberate, timely increase in speed to match surrounding traffic.
Doing It Smoothly
A smooth, progressive increase in speed is easier to control and less jarring for passengers than an abrupt burst of acceleration.
Where the Line Is Crossed
Increasing speed becomes speeding once it exceeds the posted limit or what is reasonable for conditions, regardless of the original reason for accelerating.