Passengers are 100% legal on ATVs factory designed to carry them and side-by-side (ORV) vehicles.
For on-road riding, an ATV/ORV driver must:
- be at least 16 years old
- hold at least a valid G2 or M2 licence
- wear an approved motorcycle helmet, securely fastened under the chin with a chin strap
- wear a seat belt, where provided
- travel at speeds less than the posted speed limit, as outlined below
For on-road riding, a passenger on an ATV/ORV:
- cannot be under the age of eight
- must wear a seat belt or use foot rests, when applicable
- must wear an approved motorcycle helmet, securely fastened under the chin with a chin strap
More information can be found here.