# Montana Highway 3

Montana Highway 3 (MT 3) is a highway in central Montana extending north from Billings to Great Falls.

## Route description

At its southern end, MT 3 begins at I-90 in Billings and travels northwest 47 miles (76 km) to US 12 near Lavina – this is the only section of MT 3 that is not concurrent with a US highway. MT 3 joins US 12 and travels 45 miles (72 km) west to Harlowton, where it leaves US 12 and joins US 191, and travels north for 39 miles (63 km) to Eddie's Corner (near Moore). At Eddie's Corner, MT 3 turns west, leaving US 191 and joining the US 87 / MT 200 concurrency, and travels west 65 miles (105 km) to Armington where US 89 joins the highway. The four highways continue 23 miles (37 km) to Great Falls, where it follows a 0.8-mile (1.3 km) concurrency with I-315 and ends at I-15.
MT 3 is part of the Camino Real Corridor (Corridor 27), a High Priority Corridor that connects El Paso, Texas to the Canada–United States border at Sweet Grass, Montana. The corridor is anchored by Interstate 25 and is part of the larger Ports-to-Plains Alliance. MT 3 is connected to the Canadian border via I-15, and is connected to I-25 in Buffalo, Wyoming via I-90.

## Major intersections

| County | Location | mi | km | Destinations | Notes |
| Yellowstone | Billings | 0.000 | 0.000 | I-90 / US 212 to I-94 – Butte, Sheridan | I-90 exit 450; US 212 is unsigned |
| Yellowstone | Billings | 1.298– 1.369 | 2.089– 2.203 | I-90 BL (Montana Avenue / 1st Avenue North) | One-way couplet |
| Yellowstone | Billings | 3.499 | 5.631 | Main Street to US 87 – Billings Logan International Airport | Roundabout |
| Golden Valley | ​ | 47.010 | 75.655 | US 12 east – Roundup, Forsyth | Southern end of US 12 concurrency |
| Golden Valley | Ryegate | 63.285 | 101.847 | S-238 north / S-300 south – Ryegate Airport | |
| Wheatland | Shawmut | 76.929 | 123.805 | S-297 north | |
| Wheatland | Harlowton | 92.188 | 148.362 | US 12 west / US 191 south – Harlowton, Big Timber | Northern end of US 12 concurrency; southern end of US 191 concurrency |
| Wheatland | Judith Gap | 109.990 | 177.012 | S-297 south | |
| Fergus | Eddies Corner | 131.421 | 211.502 | US 87 south / US 191 north / MT 200 east – Lewistown | Northern end of US 191 concurrency; southern end of US 87/MT 200 concurrency |
| Judith Basin | ​ | 137.574 | 221.404 | S-239 west – Hobson, Utica | |
| Judith Basin | Moccasin | 141.350 | 227.481 | S-426 north | |
| Judith Basin | ​ | 146.367 | 235.555 | S-207 north – Benchland | |
| Judith Basin | ​ | 153.314 | 246.735 | S-541 south | |
| Judith Basin | ​ | 159.419 | 256.560 | MT 80 north – Stanford, Fort Benton | |
| Judith Basin | Geyser | 174.711 | 281.170 | S-551 north – Geyser | |
| Judith Basin | ​ | 185.591 | 298.680 | S-427 south – White Sulphur Springs | |
| Cascade | Armington Junction | 196.118 | 315.621 | US 89 south – Monarch, White Sulphur Springs | Southern end of US 89 concurrency |
| Cascade | ​ | 199.721 | 321.420 | S-331 north – Belt | |
| Cascade | ​ | 212.577 | 342.110 | S-227 north / S-228 south – Sand Coulee, Highwood | |
| Cascade | Great Falls | 215.596 | 346.968 | US 87 Byp. north (57th Street) – Malmstrom AFB | |
| Cascade | Great Falls | 218.696– 218.776 | 351.957– 352.086 | US 87 north (14th Street S / 15th Street S) – Black Eagle, Havre | Northern end of US 87 concurrency; one-way couplet |
| Cascade | Great Falls | 219.429– 219.514 | 353.137– 353.274 | I-15 BL north (5th Street S / 6th Street S) | Southern end of I-15 Bus. concurrency; one-way couplet |
| Cascade | Great Falls | 220.942 | 355.572 | I-315 begins / Fox Farm Road, 6th Street SW | Eastern terminus of unsigned I-315; southern end of I-315 concurrency; southern end of freeway |
| Cascade | Great Falls | 221.435 | 356.365 | 14th Street Southwest | I-315 exit 0 |
| Cascade | Great Falls | 221.770 | 356.904 | I-15 / US 89 north / MT 200 west – Helena, Shelby I-315 ends / I-15 BL ends | MT 3 / I-315 / I-15 BL northern terminus; I-15 exit 278 |
| 1.000 mi = 1.609 km; 1.000 km = 0.621 mi Concurrency terminus ||||||