A first DUI conviction in Montana carries a mandatory minimum of 24 hours in jail, a $685 fine, completion of ACT (Assessment, Course, and Treatment), and a six-month driver’s license suspension. You may be eligible for a probationary license during this suspension. Penalties – including jail time, fines, treatment requirements, and license suspension – become more severe with each subsequent DUI conviction. A DUI conviction also results in 10 points on your driving record; accumulating 30 points within three years designates you as a habitual traffic offender.