Utah is about 1.8 times smaller than Montana.

Montana is approximately 376,979 sq km, while Utah is approximately 212,751 sq km, making Utah 56.44% the size of Montana. Meanwhile, the population of Montana is ~989,415 people (1.8 million more people live in Utah).
Tip: This to-scale comparison of Montana vs. Utah uses the Mercator projection, which distorts the size of regions near the poles.