via I-90
The drive from Billings to Boise takes approximately 7h 45min, covering 540 miles via I-90. Under normal conditions, expect to spend around $63 on gas.
Travel time can vary — during peak hours, weekends, or holidays, the journey may take 10–11+ hours. For the fastest trip, leave early morning (before 7 AM) or travel on weekday evenings.
Traffic is usually worst during weekday rush hours (7–9 AM, 4–7 PM) and holiday weekends.
Plan rest stops every 2-3 hours on longer drives. Check traffic conditions before departure and keep your tank above quarter-full.
This trip can typically be done on a single tank of gas.
For a long drive like Billings to Boise, plan to depart early in the morning. This lets you cover most of the distance before afternoon traffic builds up. Consider breaking the trip with a lunch stop midway.
✈️ Flying is faster when you factor in airport time. Flight time is ~1h 5m but add ~2.5 hours for check-in, security, and boarding.
Estimated times and prices. Bus/train availability varies by route. Driving gives the most flexibility for stops and schedules.
Popular cities along the route for rest, food, or fuel:
The long road trip from Billings to Boise follows I-90 for 540 miles, with an estimated travel time of 7h 45min under normal conditions. Fuel costs run approximately $63 at current prices, assuming average fuel efficiency of 30 MPG. Early morning (6-8 am) is generally the best window to depart for the smoothest ride.
This is a serious 540-mile road trip that spans multiple states and regions. Plan for at least one overnight stop, pack emergency supplies, and make sure your vehicle is road-trip ready with fresh oil and properly inflated tires. Popular stopping points include Big Sky, Yellowstone, Grand Teton — great options for grabbing a meal, fueling up, or stretching your legs.