New Mexico's primary keep-right rule is found in New Mexico Statutes §66-7-308.
On roadways of sufficient width, vehicles generally must be driven on the right half of the roadway unless a statutory exception applies.
A vehicle traveling at less than the normal speed of traffic at the time, place and under the conditions then existing 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.
The 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.
New Mexico also prohibits driving a motor vehicle at such a slow speed that it impedes the normal and reasonable movement of traffic unless the reduced speed is necessary for safe operation or required by law.
Official signs may also direct slow-moving traffic to use a designated lane, and drivers must obey those lane-use signs.
New Mexico therefore follows the traditional slower-traffic keep-right model rather than a statewide rule making the far-left lane exclusively a passing lane on every multilane highway.
Exceptions
- Overtaking and passing another vehicle traveling in the same direction.
- Preparing for a lawful left turn at an intersection or into a private road or driveway.
- The right half of the roadway is closed because of construction or repair.
- Traveling on certain three-lane roadways under applicable lane rules.
- Traveling on a roadway designated and posted for one-way traffic.
- Driving at a reduced speed when necessary for safe operation or required by law.
Penalties
Violations of New Mexico's keep-right, minimum-speed or lane-use rules may result in a traffic citation and penalty assessment.
The exact amount due depends on the specific section charged and applicable assessments. Drivers should verify the amount shown on the citation or with the court handling the case.
Official Source
New Mexico Statutes §§66-7-308 and 66-7-305 - Keep Right and Minimum Speed Rules
Last verified: October 11, 2026