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Montana Speed Limits: What To Know

If you’re driving through Montana, you need to know the state’s speed limits.

Like other states in the U.S., Montana has multiple statutory speed limits which dictate the maximum speeds on different types of roads.

These speed limits are also known as prima facie speed limits.

While speed limits should be posted when you’re driving Montana roads, you can’t always rely on good signage along your route. (And a missing sign won’t stop you from getting a ticket if you’re speeding.)

So, if you want to avoid a ticket when driving in Montana, you might want to keep these basic speed limits in the back of your mind.

MT speed limit

Montana Freeway Speed Limit

Freeways are defined as roads with controlled-access, which means they have on and off ramps and no immediate access to businesses or residential areas.

Basically, they’re interstates.

The maximum speed limit on freeways/interstates in Montana is 80 mph in rural areas and 65 mph within city limits, unless otherwise posted.

Montana Highway Speed Limit

Highways in Montana are defined as main roads with immediate access (turn-offs and driveways) to businesses or residential areas.

These roads may be two-lane roads or multi-lane roads.

The maximum speed on highways in Montana depends on the time of day.

During daylight hours, the statutory speed limit is 70 mph on Montana highways.

At night (between sunset and sunrise), the statutory speed limit is 65 mph on Montana highways.

Drivers may legally exceed the speed limit by 10 mph on two-lane highways when passing in designated passing zones.

Montana Residential & Business District Speed Limit

Residential districts in Montana are any areas that have a majority of residential buildings, such as single-family houses or apartment blocks.

Business districts are any areas that have a majority of businesses accessed directly from the road (typically downtown streets).

The speed limit in residential neighborhoods and business districts in Montana is 25 mph, unless otherwise posted.

Neighborhoods, especially those with private-access streets, often have lower speed limits.

Montana Truck Speed Limit

The following vehicles are considered “trucks” for the purposes of speed limits in Montana:

  • Semis/trucks with 1 ton or more rated load capacity

The maximum speed limit for vehicles that meet the definition of “truck” in Montana is 70 mph on freeways/interstates and 65 mph on highways.

Follow The Speed Limit

When it comes to maximum speeds in Montana, it’s always best to play it safe.

When in doubt, in an area with homes or businesses directly next to the road, assume the speed limit is 25 mph.

In parking lots and at blind intersections, assume the speed limit is 15 mph.

By assuming the lowest maximum speed limits in most instances, you can avoid a ticket and help keep everyone safe. As long as you keep with the general flow of traffic.

It’s not safe to go 20 mph below the speed limit either.