Your construction company is probably a motor carrier.

A construction company is a motor carrier under federal rules if it uses a truck, trailer, or combination rated at 10,001 pounds or more to haul its own equipment or materials across state lines. FMCSA calls this a private motor carrier, and most of the same safety rules apply.

This is not a small group. In FMCSA’s 2024 Pocket Guide to Large Truck and Bus Statistics, 197,563 active carriers registered as private only, and another 67,667 as both private and for-hire. That is about one in three carriers on the federal books. Many of them are contractors, utilities, and distributors who would never describe themselves as trucking companies.

What makes a company a motor carrier?

A motor carrier is any person or business that transports property by commercial motor vehicle, either for pay or for its own business. The federal definition in 49 CFR 390.5T splits motor carriers into two kinds:

• For-hire motor carrier: moves goods or passengers for compensation.
• Private motor carrier: moves property or passengers by commercial motor vehicle and is not for-hire.

There is no minimum fleet size and no test of what your main business is. A paving company with one tandem dump truck and a pickup pulling an equipment trailer meets the definition the same way a 40-truck freight hauler does.

The practical difference between the two is operating authority. A private carrier hauling its own equipment and materials needs a DOT number but not an MC number. That changes the day you haul for someone else. Moving another contractor’s mini excavator to their job for a fee is for-hire transportation, and for-hire work across state lines requires operating authority and federal insurance filings.

When does a construction truck become a commercial motor vehicle?

A truck or combination becomes a commercial motor vehicle in interstate commerce when its weight rating or actual weight, whichever is greater, is 10,001 pounds or more. Under 49 CFR 390.5T, it also qualifies at any weight if it carries hazardous materials in a quantity that requires placards, or if it is designed or used to carry more than 15 people including the driver, not for pay.

The detail that catches contractors is the combination rating. When a pickup tows a trailer, the rule looks at the pickup’s rating plus the trailer’s rating. An empty trailer still counts, because the rating is what matters, not what is on it today.

One exception helps here. A pickup’s own combination rating does not count when it is not towing anything. A truck sticker that says it can tow 20,000 pounds does not make the bare truck a commercial motor vehicle. For a breakdown of whether you need a DOT number by vehicle type, see our full guide.

Does staying in one state get you out of it?

Staying in one state takes you out of most federal rules, but usually not out of the rules themselves. Most states adopt the federal safety regulations for their own intrastate carriers, and many issue DOT numbers to them.

Two things decide where you land:

1. Whether any trip crosses a state line. Under 49 CFR 390.5T, interstate commerce includes any move between a place in one state and a place in another. A Kansas City contractor who takes one job across State Line Road is an interstate carrier for that work.
2. Your state’s intrastate threshold. Some states apply their rules at 10,001 pounds, the same as the federal line. Others start at 26,001 pounds. The difference decides whether your pickup and trailer setups are regulated at all inside your state.

If your company works near a state line, plan as an interstate carrier. It is easier to set up the files once than to rebuild them after a roadside inspection on the wrong side of the border.

What does a construction company have to do once it is a motor carrier?

At 10,001 pounds in interstate commerce, a private carrier takes on driver files, vehicle maintenance records, hours-of-service rules, and registrations. At 26,001 pounds the driver also needs a CDL, which brings drug and alcohol testing with it.

A few of these surprise contractors more than others. Unified Carrier Registration applies to private carriers of property, not only trucking companies. For the 2027 registration year, which opened October 1, 2026, the fee for a fleet of zero to two vehicles is $55, up from $46 (49 CFR 367.50). Federal minimum insurance levels in Part 387 apply to for-hire carriers and to carriers hauling placarded hazardous materials, so a private carrier hauling ordinary equipment is not on that federal schedule. Your state, your insurer, and your general contractor will still set their own limits.

Vehicles over 26,000 pounds or with three or more axles also bring IRP apportioned plates and IFTA fuel tax reporting when they run in more than one state. Those are handled by your base state, not FMCSA. For the full set of requirements for fleets between 10,001 and 26,000 pounds, see our non-CDL fleet guide.

Are there rules written specifically for construction?

Yes. Drivers who mainly haul construction materials and equipment can restart their 60-hour or 70-hour weekly clock with 24 hours off duty instead of 34, under 49 CFR 395.1(m). The definition in 49 CFR 395.2 sets three conditions:

1. The load is construction or paving materials, construction equipment, or construction maintenance vehicles.
2. It is going to or from an active construction site, meaning a site between mobilization and final completion.
3. The driver stays within 75 air miles of their normal work reporting location. A state may set its own limit between 50 and 75 air miles for moves entirely inside that state.

The restart does not apply to vehicles placarded for hazardous materials, and the federal rule says it does not override state law. Georgia’s Department of Public Safety, for example, still posts a construction flyer quoting the pre-2015 figure of 50 air miles. When your state’s guidance and the federal text disagree, ask the state enforcement agency which number it applies.

Most construction drivers also qualify for the short-haul exceptions in 49 CFR 395.1(e). A driver who stays within 150 air miles (172.6 road miles) of the normal work reporting location, returns there each day, and is released within 14 hours can keep a time record instead of logs or an ELD. Drivers who do not need a CDL get extra room: they can drive up to the 16th hour on two days in any seven, as long as they return to the same location at the end of each day.

These exceptions change hours and logging. They do not remove the driver file, the medical certificate, or the vehicle inspection rules.

Who at the company is responsible?

The company is the motor carrier, and so are the people who run its trucks. The definition in 49 CFR 390.5T includes employees responsible for hiring, supervising, training, assigning, or dispatching drivers, and employees who inspect and maintain vehicles.

In a construction company, that is usually the superintendent who decides who drives the lowboy tomorrow, the office manager who keeps the files, and the shop mechanic who signs off on the trailer brakes. None of them may think of themselves as a trucking safety manager. Under the regulation, each of them is part of the motor carrier.

The records also have to live somewhere. Federal rules let FMCSA ask for your driver, hours, and maintenance records at your principal place of business, and you have 48 hours, not counting weekends and federal holidays, to produce them. A folder in a superintendent’s truck does not meet that standard.

How does a construction company get a DOT number now?

New DOT numbers are issued through Motus, FMCSA’s registration system at motus.dot.gov. Motus replaced the old Unified Registration System in May 2026, and it now handles new applications, updates, and biennial filings (FMCSA registration).

1. Confirm you need one. The Dotra USDOT checker walks through weight, interstate travel, and your state’s threshold.
2. Apply in Motus as a private carrier of property. Expect an identity verification step. The DOT number itself is free.
3. Skip operating authority unless you also haul for pay.
4. Register for UCR at ucr.gov before you run interstate.
5. Mark every qualifying truck with your company name and DOT number.
6. Set up driver qualification files and maintenance records before the first trip, not after the first inspection.

FMCSA has temporarily paused enforcement of missed biennial updates while carriers move into Motus. Treat that as a grace period, not a waiver.

The work is already trucking work.

Most contractors find out they are a motor carrier the hard way: at a weigh station, at a roadside inspection, or when a general contractor’s insurer asks for a DOT number they do not have. The rules did not change that day. They applied from the first time the trailer crossed 10,001 pounds and a state line.

The companies that handle this well treat their trucks the way they treat their jobsites. Someone owns safety, the paperwork is current before the work starts, and nobody is guessing when an inspector asks. We are building Dotra for the people behind every load, and that includes the crew hauling a mini excavator to a jobsite at six in the morning.

Frequently asked questions

Does my work truck and trailer need a DOT number?

Yes, if the truck and trailer ratings add up to 10,001 pounds or more and the combination ever crosses a state line for your business. The trailer’s rating counts even when the trailer is empty. If you only work in one state, your state’s own threshold decides.

Do small dump trucks need a DOT number?

Most do. Nearly every single-axle dump truck is rated well above 10,001 pounds, so it needs a DOT number for interstate work and, in most states, for in-state work as well. Once the rating reaches 26,001 pounds, the driver also needs a CDL.

Does a truck towing an equipment trailer need a CDL?

Only when the combined rating is 26,001 pounds or more and the trailer itself is rated over 10,000 pounds. That combination calls for a Class A CDL. A heavy-duty pickup pulling a large gooseneck can reach that line, so check both door stickers before you assign the driver.

Do construction company pickups need DOT inspections?

A pickup that is part of a commercial motor vehicle, alone or with its trailer, needs a documented annual inspection under 49 CFR 396.17. It can also be stopped for a roadside inspection like any other commercial vehicle. A pickup rated under 10,001 pounds that never tows a trailer is not covered by these rules.

Can my employees drive the company truck without a medical card?

Not in interstate commerce when the truck or combination is rated 10,001 pounds or more. Federal rules require those drivers to carry a current medical certificate, and the company must keep a copy in the driver’s qualification file. For in-state-only work, your state’s rules decide.

Do non-CDL drivers have to take a DOT drug test?

No. Federal drug and alcohol testing under 49 CFR Part 382 applies to drivers who are required to hold a CDL. You can still test non-CDL drivers under your own company policy, but they cannot be placed in the DOT testing program.

What is the difference between a DOT number and an MC number?

A DOT number identifies your company to FMCSA and tracks your safety record. An MC number is operating authority to haul other people’s goods for pay across state lines. A construction company hauling only its own equipment and materials needs the DOT number and not the MC number.