Here's (Roughly) How Many Semi-Trucks Are On US Roads Each Day

Let's just be honest — drivers sometimes dread when the highway is full of semi-trucks. It can be a bit tricky to share the road with them, given how large the biggest ones are. But how many are you realistically going to run into during your commute? As of February 2025, there are 2.97 million semi-trucks registered in the United States. While not every one of these semi-trucks is on the road all at once, it's safe to say they spend a lot of time on the road. A single semi-truck drives an average of 45,000 miles a year, making them one of the more frequent trucks you'll come across on your drive. 

Semi-truck drivers spend a lot of time driving due to the long distances they must commute for work. While semi-trucks only make up 1% of registered vehicles in the United States, according to the Federal Motor Carrier Safety Administration, they are on the road far more often. The total miles traveled by vehicles every year across the U.S. is 3 trillion, but semi-trucks account for 184 billion miles alone.

It's safe to say that you're bound to run across a semi-truck during your drive due how often they're on the road, but that doesn't have to automatically mean danger. It's common for drivers to hate on semi-trucks because of their intimidating size. Compared to a car, semi-trucks also have large blind spots on every side, making it dangerous to get too close at certain angles. 

Luckily, there are laws in place to ensure semi-truck drivers are safe on the road. First, there are hours of service regulations that prohibit semi-truck drivers from being behind the wheel if they've already been driving for 15 hours. This is meant to limit the number of tired drivers behind the wheel, preventing sloppy driving and accidents. Every state has a varying version of the "left lane" law as well, which generally means semi-trucks should remain in the "slow lane" unless they are passing. This keeps semi-truck drivers from frequently changing lanes, which can be potentially dangerous due to their blind spots. To combat this, semi-trucks are outfitted with extra mirrors for better vision, but this is not a widely implemented change just yet.