Key takeaways
- Weigh stations check weight, credentials and safety of commercial vehicles – mostly trucks.
- Who must stop depends on the state; thresholds commonly start at 10,001 lbs gross vehicle weight rating for commercial vehicles.
- Private RVs and personal pickups usually don’t have to stop – but posted signs always apply.
- Bypass systems (PrePass, Drivewyze) and weigh-in-motion let pre-cleared trucks stay on the highway.
On this page
What is a weigh station?
A weigh station is a checkpoint next to a highway where commercial vehicles are weighed and inspected. Most are run by the state’s department of transportation, state police or a motor carrier enforcement unit – which is why drivers often call them “the DOT” or “the scales”.
We list 511 weigh stations across the US on our weigh station map.
Weigh stations exist for two reasons. Overweight trucks damage roads and bridges far more than legal ones – pavement wear grows sharply with axle weight. And weigh stations are a convenient place to check whether truck and driver are safe and legal to be on the road.
Who has to stop at a weigh station?
Each state sets its own rule, and the signs before each station say who must enter. In general:
- Commercial trucks above the state’s weight threshold must stop when the station is open. Many states use 10,001 lbs gross vehicle weight rating, the federal threshold for a commercial motor vehicle; some use higher numbers.
- Buses and vehicles carrying hazardous materials may have to stop regardless of weight, depending on the state.
- Agricultural vehicles have different rules in many states.
- Private passenger vehicles never have to stop.
If a sign says “All trucks must enter”, it means what it says – even if you’re unsure whether your vehicle counts. Pulling in when you didn’t need to costs a minute; driving past when you should have stopped can cost a fine.
Do RVs have to stop at weigh stations?
Usually not. Recreational vehicles used privately are generally exempt from weigh station stops in most states, even large motorhomes. A few states word their signs broadly, and an RV used commercially (for example, by a business) can fall under commercial rules. When in doubt, follow the sign.
Do pickup trucks have to stop at weigh stations?
A pickup used for personal purposes doesn’t have to stop. A pickup used for business – especially with a trailer, where the combination’s weight rating can exceed 10,001 lbs – may have to. Hotshot drivers and contractors with heavy trailers are the most common case.
What happens at a weigh station
- Signs: Several miles ahead, signs announce the weigh station and whether it is OPEN or CLOSED.
- Entering: If it’s open and your vehicle is covered, you take the exit ramp. Watch the posted speed – often very low on the scale.
- The scale: You roll slowly across a static scale or a weigh-in-motion scale built into the ramp. It measures the weight on each axle or axle group and the gross weight.
- The signal: A light or a loudspeaker tells you to return to the highway, or to pull around and park.
- Inspection: If you’re asked to park, an officer may check your credentials, logbook or electronic logging device, and the vehicle itself.
Most trucks spend under a minute at an open station. Inspections take longer – a full roadside inspection can take an hour.
Weight limits
On the Interstate System, federal law sets the core limits:
| Limit | Federal maximum |
|---|---|
| Gross vehicle weight | 80,000 lbs |
| Single axle | 20,000 lbs |
| Tandem axle | 34,000 lbs |
| Axle groups | Federal Bridge Formula |
States can allow more on their own roads and issue permits for oversize and overweight loads. Exceeding a limit typically means a fine based on the overage, and the driver may have to shift or remove part of the load before continuing.
What DOT officers check
Beyond weight, officers can check a driver’s license and medical certificate, hours-of-service records, registration and permits, and the vehicle’s condition – brakes, tires, lights and load securement. Inspections follow standard levels set by the Commercial Vehicle Safety Alliance; a serious defect can put the vehicle or driver out of service until it’s fixed.
Bypass systems and weigh-in-motion
Stopping every truck at every station would clog the highways. That’s why many states pre-screen trucks at highway speed. Weigh-in-motion sensors in the road estimate weight as the truck drives over them, and electronic bypass programs check the carrier’s safety record and credentials.
Drivers in these programs get a signal in the cab – a green light or tone to bypass, red to pull in. PrePass uses a windshield transponder; Drivewyze works through an app or the truck’s electronic logging device. Which stations take part in which program varies by state. A green light only applies to that station; the next one may still call you in.
Are weigh stations open 24 hours?
Some are, many aren’t. Hours depend on staffing, and states open stations at irregular times so drivers can’t plan around them. The OPEN/CLOSED sign before the station is the only reliable status. Closed stations are often used by truck drivers as a short parking spot – check the signs, since some states prohibit it.
Tips for drivers
- Weigh first on a certified truck scale at a truck stop after loading – it’s cheap and avoids surprises. See our truck scales page.
- Keep your documents and electronic logs ready before you pull in.
- Follow the speed limit on the scale exactly; going too fast can force a re-weigh.
- Know the stations on your route: our weigh station map lists them by state, with direction of travel.
Find the next rest area on your route
Every stop with direction of travel, exit and amenities.
Frequently asked questions
Do RVs have to stop at weigh stations?
Usually not. Privately used RVs are exempt in most states, even large motorhomes. If a sign says all trucks or all vehicles over a weight must stop and you’re unsure, pull in.
Do pickup trucks have to stop at weigh stations?
Personal pickups don’t. Pickups used commercially, especially with a trailer that brings the combination over the state’s threshold (often 10,001 lbs), may have to.
What does “weigh station DOT” mean?
Truck drivers often call weigh stations “the DOT” because many are run by the state’s department of transportation or its enforcement officers, who check weight, paperwork and safety.
What happens if you skip an open weigh station?
If your vehicle was required to stop, you can be pulled over and fined. Many stations watch the highway with cameras and officers can follow vehicles that bypass.
Sources
- FMCSA – What is a commercial motor vehicle (49 CFR 390.5)
- FHWA – Federal size and weight regulations (23 CFR 658.17)
- FHWA – Bridge Formula Weights
- CVSA – North American Standard Inspection Program
Rules change. If you find an error, tell us – see our editorial policy for how we check facts.
IT enthusiast · builds free data tools
Sinan is an IT enthusiast from Bad Homburg, Germany, who builds free tools that turn open data into answers for everyday problems – from bike pumps (bike-pump.com) to rest stops. He doesn’t drive a truck for a living; every rule in these guides comes from the state or federal source linked next to it.