Decatur, Illinois to Great Falls: Road Trip Guide & Distance

How far is Decatur, Illinois from Great Falls?

The distance from Decatur, Illinois to Great Falls is 1229.9 miles (1979.4 km) as the crow flies. Great Falls is located WNW of Decatur, Illinois. By car, the driving distance is approximately 1475.9 miles, taking about 29h 41min. A direct flight would take roughly 2h 58min. Both are located in United States — Decatur, Illinois in Illinois and Great Falls in Montana.

This is a serious multi-day road trip! We strongly recommend breaking this journey up with an overnight stay to ensure you arrive safely and refreshed. Since you'll be heading mostly West, pack a good pair of sunglasses if you plan to drive during the late afternoon to avoid the harsh sun glare. For a trip of this distance, flying is significantly faster. However, driving offers the flexibility to explore stops along the way.

Coordinates come from public place data for Decatur, Illinois and Great Falls. The driving distance is estimated from straight-line distance with a road-factor model, so confirm the route in your navigation app. Fuel, flight, bus, and train values are planning estimates and can change by date, provider, road closures, and border rules.