Delaware's general keep-right rule is found in 21 Del. C. §4114.
A vehicle traveling at less than the normal speed of traffic under the conditions then existing generally must be driven in the right-hand lane available for traffic, or as close as practicable to the right-hand curb or edge of the roadway.
This slower-traffic rule does not apply when the driver is overtaking and passing another vehicle traveling in the same direction or when preparing for a left turn at an intersection or into a private road or driveway.
Delaware also has a specific left-lane restriction in §4114A for designated portions of State Route 1 and Interstate 495. On those roadways, a vehicle generally may not travel in the left lane unless one of the statutory exceptions applies.
Those exceptions include overtaking and passing, entering or leaving the roadway, avoiding an obstruction, responding to emergency conditions, traffic congestion, or complying with another law or regulation.
In addition, Delaware law provides that a driver traveling below the posted speed limit in the left lane of a multilane roadway may be penalized when that driving impedes the ability of one or more vehicles to pass, except when making a lawful left turn or otherwise lawfully exiting to the left.
Exceptions
- Overtaking and passing another vehicle traveling in the same direction.
- Preparing for a lawful left turn.
- Entering, leaving or continuing on the roadway where left-lane use is necessary.
- Avoiding an obstruction.
- Responding to emergency conditions.
- Traffic conditions or congestion that make left-lane use necessary.
- Following another law, regulation, traffic-control device or lawful direction.
Penalties
For a violation of Delaware's special left-lane restriction under §4114A, the civil penalty is not less than $25 and not more than $75 for a first occurrence.
For a subsequent occurrence, the civil penalty is not less than $57.50 and not more than $95.
Other keep-right or passing violations may be subject to different penalties depending on the specific section charged.
Official Source
21 Del. C. §§4114 and 4114A - Driving on Right Side of Roadway and Left-Lane Restrictions
Last verified: October 10, 2026