State law page

New Mexico Booster Seat Laws & Requirements (2026)

Under 1 yrs in rear-facing seat, in rear seat, if available | 1-4 yrs or under 40 lbs in child safety seat | 5-6 yrs or under 60 lbs in booster seat

Field	New Mexico snapshot
Age requirement	Under 1 yrs in rear-facing seat, in rear seat, if available \| 1-4 yrs or under 40 lbs in child safety seat \| 5-6 yrs or under 60 lbs in booster seat
Height requirement	No height threshold listed in GHSA summary.
Weight requirement	See child-restraint rule; includes weight language where listed.
Fine / penalty	Verify fine with state source; GHSA notes first-offense fines vary by state.
Last checked	GHSA reviewed by SHSOs June 2025; extracted 2026-07-23
Verification level	Index source; official state verification pending
Child restraint required	Under 1 yrs in rear-facing seat, in rear seat, if available \| 1-4 yrs or under 40 lbs in child safety seat \| 5-6 yrs or under 60 lbs in booster seat
Adult safety belt permissible	7-17 yrs
Verification level	Index source; official state verification pending

Sources

Law and source links

Safety guidance

Even when New Mexico law allows a seat belt, NHTSA, CDC, and AAP guidance may still recommend a booster until the vehicle belt fits properly.

Understand age, height, weight, and seat belt fit.

See when children typically start and stop using boosters.

Know when to move from harnessed seat to booster.