It is about 144.13 miles according to MapQuest.
The best-known Billings is the largest city in Montana and is located about 54 miles north of its southern border with Wyoming. The city is on U.S. Interstate 90 (which actually curves around it to the southeast) about six miles west of the I-90 / I-94 intersection. Billings is found at 45o 47' N latitude and 108o 30' W longitude. (Cities or towns named Billings can also be found in Missouri, New York, and Oklahoma, and there is a Billings County in North Dakota and a Billings Township in Michigan.)
The driving distance from Winnipeg, Manitoba, Canada to Billings, Montana is 826 miles per MapQuest. The driving time per MapQuest is 11 hours and 40 minutes.
It is 125.96 miles according to MapQuest.