Trucking rules, explained
Updated September 28, 2026
Interstate trucking is any haul that crosses a state line, or that is one leg of a trip that starts or ends in another state or country. Intrastate trucking is everything else: freight that starts, moves and ends inside one state.
Federal safety rules follow interstate commerce. Your state writes most of the rules for intrastate trucking, inside limits that federal law sets.
This guide quotes the federal definitions word for word, shows why a trip that never leaves your state can still be interstate, and lists what changes for drivers and carriers. It is a plain-language summary, not legal advice.
The Federal Definitions
The definitions live in 49 CFR 390.5T, the list of terms for the federal motor carrier safety rules. Interstate commerce means trade, traffic, or transportation in the United States that fits one of three patterns. Here is each one, in the rule’s words and in plain words.
1
It crosses a state line
“Between a place in a State and a place outside of such State (including a place outside of the United States)”
The truck starts in one state and ends in another state or country. A load from Denver to Salt Lake City is interstate.
2
It leaves the state on the way
“Between two places in a State through another State or a place outside of the United States”
Both ends sit in one state, but the route passes through another state or country. The trip is interstate even though it starts and ends at home.
3
It is one leg of a longer trip
“Between two places in a State as part of trade, traffic, or transportation originating or terminating outside the State or the United States”
The truck never leaves the state, but the freight’s journey began or will end outside it. The dashed line is the freight’s trip before the truck picks it up.
The same section defines intrastate commerce as “any trade, traffic, or transportation in any State which is not described in the term ‘interstate commerce.’” In other words, intrastate is whatever is left over.
FMCSA’s own FAQ puts it this way: “If you perform trade, traffic, or transportation exclusively in your business’s domicile state, this is considered intrastate commerce.”
When an In-State Trip Is Still Interstate
Pattern 3 is the one that surprises people. The test is not only where the truck goes. It is also where the freight came from and where it is headed.
Car hauling runs into this pattern all the time. New vehicles often reach a port by ship or a rail ramp by train. Then a truck carries them the last miles to a dealer, sometimes without crossing a state line. The rule’s wording covers a leg like that: two places in one state, as part of transportation that began outside the state or the country.
Your own move is a question of facts. Whether a given trip is interstate depends on the whole shipment, not just the truck’s route. If you are not sure about your own freight, ask FMCSA or your state’s motor carrier office before you plan around it.
What Changes for Drivers
Some rules apply to every truck driver. Others depend on which side of the line you drive on.
| Rule | Interstate | Intrastate |
|---|---|---|
| Minimum age | 21, under 49 CFR 391.11 | Set by your state. Federal rules let states go no lower than 18. |
| Whose safety rules | The federal rules in 49 CFR parts 390 to 399 | Your state’s rules, which may differ from the federal ones only in allowed ways |
| Hours of service | The federal limits in 49 CFR part 395 | Your state’s limits. States may allow up to 12 hours of driving, and no driving after 16 hours on duty. |
| CDL rules | Part 383 applies | Part 383 applies too |
| Medical card | Needed if you certify non-excepted interstate | Set by your state’s driver rules |
One thing does not change: the CDL rules in 49 CFR part 383 apply to anyone who drives a commercial motor vehicle as that part defines it, in interstate or intrastate commerce. For the full definition, see our guide to what counts as a commercial motor vehicle.
When you apply for a CDL, you also certify which kind of driving you do. There are four choices: non-excepted interstate, excepted interstate, non-excepted intrastate and excepted intrastate. A driver who hauls freight across state lines with no exception certifies non-excepted interstate. That driver must meet the federal driver rules in part 391 and carry a medical examiner’s certificate. Our guide to the DOT physical explains the exam and the four categories.
For interstate driving hours, see our guide to hours of service for car haulers.
What Changes for Carriers
The company side changes too. Two federal registrations follow interstate work:
- A USDOT number. FMCSA says companies that run commercial vehicles hauling cargo or passengers in interstate commerce must register and have a USDOT number. Intrastate carriers that haul hazardous materials needing a safety permit must register too.
- Operating authority. In general, a company that hauls federally regulated freight owned by others, for pay, in interstate commerce also needs operating authority, often called an MC number. Private carriers hauling their own cargo do not.
Staying intrastate does not always mean no USDOT number. Some states require one from their own intrastate carriers. FMCSA’s list, last updated September 3, 2025, names 38 states plus Puerto Rico. Check with your state’s agency. For the federal steps, read our guide to getting your own trucking authority.
Is There an Intrastate CDL?
There is one CDL, issued by your home state under the same federal part 383. There is no separate federal intrastate license. What differs is the self-certification you make, and any restriction printed on the license. Federal rules give states a code for that: K means “Intrastate only.”
Age is where most drivers feel the split. The federal minimum for interstate driving is 21. So a CDL holder under 21 generally cannot drive a commercial motor vehicle across state lines. Your state decides whether younger drivers can drive intrastate, and the federal floor for intrastate drivers is 18.
Moving from intrastate to interstate work means meeting the federal driver rules first, including the age and the medical certificate. Your state’s licensing agency can tell you how to change your certification.
Already 21 or older, with years of CDL-A miles and 9-car experience? Contract with Accelerated.
Where Car Haulers Fit
At Accelerated, our contract drivers operate over the road and follow the freight. Over-the-road work takes drivers across state lines, which makes it interstate commerce under the first pattern above. Before you can contract with us, we ask for:
You also need a valid Class A CDL, an acceptable MVR, a clean safety history and a current DOT medical certificate.
Run your own truck instead? Our sub-haulers work under their own authority, with their own MC and DOT numbers, and pull the freight we post. See the sub-hauler requirements.
Interstate vs Intrastate FAQs
What is the difference between interstate and intrastate trucking?
Interstate trucking crosses a state line, passes through another state, or is one leg of a trip that starts or ends outside the state. Intrastate trucking stays inside one state from start to finish. Federal safety rules cover interstate trucking, and states set most intrastate rules.
Can a trip inside one state be interstate commerce?
Yes. The federal definition counts a haul between two places in one state as interstate when it is part of transportation that began or ends outside the state or the country. Whether your own trip qualifies depends on the facts of the shipment.
How old do you have to be to drive a truck interstate?
At least 21, under 49 CFR 391.11. For intrastate driving, your state sets the age, and federal rules do not let it go below 18.
Is an intrastate CDL different from an interstate CDL?
It is the same license, issued by your state under the same federal rules. The difference is the self-certification you made when you applied, and any restriction on the license, such as the K code for intrastate only. To drive across state lines, you must meet the federal driver rules, such as the age of 21 and the medical certificate.
Do intrastate trucking companies need a USDOT number?
Federal rules require one for interstate carriers and for intrastate carriers hauling hazardous materials that need a safety permit. Many states also require a USDOT number from their own intrastate carriers, so check with your state.
Ready to Run Interstate Car-Haul Freight?
If you have 3 years of CDL-A driving and 1 year of verifiable 9-car experience, Accelerated wants to talk. Contract drivers get a $5,000 sign-on bonus, paid within your first month of activation.
Sources
Last checked September 28, 2026. States set their own intrastate rules within federal limits, so check with your state before you rely on them. This guide is a plain-language summary, not legal advice.
- 49 CFR 390.5T, definitions: interstate and intrastate commerce, commercial motor vehicle
- 49 CFR 390.3T, who the federal safety rules cover
- 49 CFR 391.11, driver qualifications (minimum age 21)
- 49 CFR 383.71, CDL applications and self-certification
- 49 CFR 383.153, what a CDL shows (restriction code K, intrastate only)
- 49 CFR 350.305, allowed state variances for intrastate commerce
- 49 CFR 390.19T, carrier identification reports
- FMCSA, What is the difference between interstate commerce and intrastate commerce?
- FMCSA, Do I Need a USDOT Number? (with the list of states)
- FMCSA, Get Operating Authority (Docket Number)