Montana Tire and Chain Laws

When the department of transportation determines tire chains or traction equipment are required, it applies to all towing units on the driver wheels of one axle. Autosocks are an approved alternative to tire chains. Where tire chains may be required, designated chain-up and chain removal areas are provided. Ref: MCA 61-9-406

Studded winter tires are permitted in Montana from October 1 to May 31 of the following year, except that one of those tires may be used for a spare in case of tire failure. School buses equipped with such tires are permitted from August 15 to June 15 of the following year. Ref: MCA 61-9-406

Between October 1 and April 30 of the following year, towing units 26,001 GVW or greater must carry tire chains or an approved traction device when traveling in an area where tire chains may be required. Ref: MCA 61-9-436

Current Signs in Use

Signs with flashing beacons affixed

road sign that reads: when flashing, chains required for towing units

Signs that flip open

road sign that reads: chains required for towing units

Locations Where Tire Chains May Be Required

Tire chains may be required for both directions of travel unless specified in the table below.

Route Mile Post Name County
I-15 Southbound 148 - 143 Elk Park Jefferson
I-15 168 - 175 Boulder Hill Jefferson
I-90 Westbound 4 - 0 Lookout Pass Mineral
I-90 228 - 241 Homestake Pass Silverbow - Jefferson
I-90 256 - 262 Cardwell Hill Jefferson
I-90 319 - 323 Bozeman Pass Gallatin - Park
I-90 Eastbound 548 - 554 Aberdeen Hill Big Horn
US-2 Westbound 7 - 4 Yaak Hill Lincoln
US-2 Eastbound 179 - 192 Goatlick Hill Flathead
US-2 Eastbound 192 - 199 Marias Pass Flathead - Glacier
US-12 Westbound 4 - 0 Lolo Pass Missoula
US-12 12 - 30 Deep Creek Canyon Broadwater - Meagher
US-12 23 - 35 MacDonald Pass Powell - Lewis and Clark
US-20 Westbound 2 - 0 Targhee Pass Gallatin
US-87 86 - 95 Lewistown Divide Fergus
US-89 25 - 33 Kings Hill Meagher - Cascade
US-89 Northbound 71 - 75 Belt Hill Cascade
US-93 Southbound 8 - 0 Lost Trail Pass Ravalli
US-93 Northbound 4 - 7 Evaro Hill Missoula
US-191 10 - 13 Fosters Hill Fergus
US-191 14 - 18 Judith Gap Hill Wheatland
US-191 84 - 91 Missouri Breaks Fergus - Phillips
US-212 46 - 54 Lame Deer Divide Rosebud
US-212 80 - 83 Home Creek Divide Powder River
US-287 56 - 64 Norris Hill Madison
MT-43 Southbound 4 - 0 Chief Joseph Pass Beaverhead - Ravalli
MT-200 86 - 93 Rogers Pass Lewis and Clark
MT-287 4 - 14 Virginia City Hill Madison
S-278 30 - 35 Big Hole Pass Beaverhead

Montana Codes Annotated

Motor Vehicles
Restrictions As To Tire Equipment
Violation of Tire Chain Or Traction Device Use
Certain Vehicles To Carry Tire Traction Devices During Winter Months