Common carrier law is the body of rules that governs businesses offering transportation to the general public, imposing three duties that ordinary companies don’t face: the duty to serve anyone who reasonably asks, the duty to charge fair and non-discriminatory rates, and near-strict liability for cargo damaged in the carrier’s possession. Passenger carriers face an additional heightened standard of care. These rules apply to trucking, rail, bus, and airline operators, and in a modified form to certain telecommunications providers.
Who Qualifies as a Common Carrier
A common carrier is any business that transports goods or people for a fee and holds itself out to the general public. Railroads, airlines, bus lines, and freight trucking companies are the classic examples, but the status attaches based on function, not industry label. If you offer transportation services to anyone willing to pay, you are almost certainly a common carrier under the law.
The line that matters is between common carriers and private (or contract) carriers. A private carrier does not serve the public at large. It negotiates individual contracts with specific customers and can decide whom to work with. A furniture manufacturer running its own delivery fleet is a private carrier. A moving company that advertises to anyone who needs to relocate is a common carrier. That public-facing commitment is what triggers everything below.
The Three Core Duties
Common carrier status carries three foundational obligations, each designed to prevent the carrier from exploiting its position as a provider of essential services.
Duty to Serve
A common carrier must accept all reasonable requests for service. Under federal law, rail carriers must provide transportation “on reasonable request,” and a carrier cannot dodge this obligation by overcommitting its capacity through private contracts; commitments that leave a carrier unable to respond to public requests are themselves considered unreasonable.1Office of the Law Revision Counsel. 49 USC 11101 – Common Carrier Transportation, Service, and Rates Motor carriers face a parallel obligation: they must provide transportation on reasonable request and ensure their service, equipment, and facilities are safe and adequate.2GovRegs. 49 USC 14101 – Providing Transportation and Service
A carrier can refuse service for legitimate reasons: the cargo is hazardous and outside the carrier’s operating authority, the vehicle is full, or the passenger poses a safety threat. What a carrier cannot do is turn away business simply because it prefers not to deal with a particular customer.
Duty of Non-Discrimination
Common carriers must treat similarly situated customers alike. A trucking company cannot charge one shipper more than another for the same route and service. In the communications context, federal law makes the principle explicit: any carrier engaged in interstate communication that gives “any undue or unreasonable preference or advantage” to one customer over another is acting unlawfully.3Office of the Law Revision Counsel. 47 USC 201 – Service and Charges The same principle runs through transportation regulation, though enforcement varies by mode and regulator.
Duty to Charge Reasonable Rates
Because common carriers often operate in markets with limited competition, the law prevents them from setting exploitative prices. Rates must be “just and reasonable,” and any charge, practice, or classification that fails that standard is unlawful.3Office of the Law Revision Counsel. 47 USC 201 – Service and Charges For rail carriers, the Surface Transportation Board can review rates when a carrier has market dominance over a particular route. For interstate household goods movers, carriers must maintain a tariff (a document listing all rates, charges, and service terms) and make it available for customer review.4Surface Transportation Board. Tariff Guidance Pricing has to be visible, and a common carrier cannot spring surprise fees on captive customers.
The Higher Standard of Care for Passengers
When a common carrier transports people rather than freight, a different rule applies. Under the common law doctrine followed in most states, passenger carriers owe the “highest degree of care,” a standard well above the ordinary negligence threshold that governs most personal injury claims. The logic is direct: when you board a bus, train, or airplane, you surrender control of your safety to the carrier. The carrier knows the condition of its vehicles, the qualifications of its crew, and the hazards along the route. You don’t.
In practice, a passenger carrier can be held liable for even minor lapses. It must warn passengers about known dangers and provide extra protection for riders who are visibly incapacitated or need assistance.
Strict Liability for Cargo
The liability standard for freight is where common carrier law diverges most sharply from ordinary business law. A common carrier is strictly liable for goods that are lost, damaged, or destroyed while in its possession. “Strictly liable” means the shipper does not have to prove the carrier was careless. The shipper only needs to show that the goods were handed over in good condition and arrived damaged, short, or not at all. Once those facts are established, the carrier is on the hook unless it can prove the loss falls into one of five narrow exceptions rooted in centuries of common law:
- Act of God: an extraordinary natural event, such as a tornado, earthquake, or unprecedented flood, that no amount of preparation could have prevented.
- Act of a public enemy: losses caused by wartime hostilities or armed conflict against the nation, not ordinary theft or vandalism.
- Act of public authority: government seizure or quarantine of the goods, such as customs officials confiscating a shipment.
- Fault of the shipper: the shipper’s own actions caused the loss, typically inadequate packaging or mislabeling.
- Inherent nature of the goods: some cargo deteriorates on its own. Perishable food spoils, certain chemicals degrade, and live animals may die in transit despite proper handling.
Even when an exception applies, the carrier does not get a free pass if its own negligence contributed to the loss. A storm might qualify as an Act of God, but if the carrier ignored weather warnings and drove straight into it, the exception evaporates. The overlap between the carrier’s negligence and the excepted cause is where most disputed claims actually get litigated.
The Carmack Amendment and Interstate Freight
For interstate shipments of goods by motor carrier or rail, the Carmack Amendment provides the governing liability framework. Codified in Title 49 of the U.S. Code, it establishes a uniform federal standard that preempts the patchwork of state laws that would otherwise apply. Under the Carmack Amendment, both the carrier that picks up the shipment and the carrier that delivers it can be held liable for actual loss or injury to the property.5Office of the Law Revision Counsel. 49 USC 14706 – Liability of Carriers Under Receipts and Bills of Lading A parallel provision applies to rail shipments.6Office of the Law Revision Counsel. 49 USC 11706 – Liability of Rail Carriers Under Receipts and Bills of Lading
The Federal Motor Carrier Safety Administration handles licensing, safety oversight, and enforcement for interstate movers, while the Surface Transportation Board oversees tariffs and liability rules, particularly for household goods.7Surface Transportation Board. Household Goods Moving
What the Shipper Has to Prove
To recover under the Carmack Amendment, a shipper must establish three things: the goods were delivered to the carrier in good condition, the goods arrived damaged or never arrived at all, and the shipper suffered a specific dollar amount in damages. Once those elements are shown, the burden shifts to the carrier to prove an exception. This is where thorough documentation at pickup and delivery becomes critical. If you did not note damage on the delivery receipt at the time of handoff, you have made the carrier’s defense much easier.
Limiting Liability by Released Value
Carriers do not always bear unlimited exposure. Under the Carmack Amendment, a motor carrier may limit its liability for non-household-goods shipments to a declared value agreed on in writing with the shipper, so long as that value is reasonable under the circumstances.5Office of the Law Revision Counsel. 49 USC 14706 – Liability of Carriers Under Receipts and Bills of Lading In practice, a carrier offers two rate tiers: a lower shipping price with capped liability, and a higher price with full coverage. The shipper picks. If you have ever seen a moving estimate that asks you to declare a shipment value, that is the released-value system at work. A liability cap buried in boilerplate that you never had a chance to review may not hold up.
Household Goods: Full Value by Default
Household goods shipments get extra protection. Unless the shipper signs a written waiver choosing a lower coverage level, the carrier’s maximum liability equals the replacement value of the lost or damaged items, up to the total declared value of the shipment.5Office of the Law Revision Counsel. 49 USC 14706 – Liability of Carriers Under Receipts and Bills of Lading This “full value protection” is the default. A carrier cannot apply reduced liability rates unless the shipper affirmatively waives the full-value standard in writing.
Filing a Cargo Claim
Federal regulations set minimum standards for how freight claims must be handled. A valid written claim needs three components: enough information to identify the shipment, a statement that the carrier is liable for the loss or damage, and a demand for a specific dollar amount.8eCFR. 49 CFR Part 370 – Principles and Practices for the Investigation and Voluntary Disposition of Loss and Damage Claims The claim must be filed within the time limit stated in the bill of lading or contract of carriage. For many shipments, that window cannot exceed nine months from delivery, or from the expected delivery date if the goods never arrived.
Once a carrier receives a properly filed claim, it must acknowledge receipt in writing within 30 days. The carrier then has 120 days to pay, deny, or offer a compromise. If it cannot resolve the claim within 120 days, it must send the claimant a written status update and continue doing so every 60 days until the matter is settled.8eCFR. 49 CFR Part 370 – Principles and Practices for the Investigation and Voluntary Disposition of Loss and Damage Claims
Damage that isn’t visible at the time of delivery, known as concealed damage, is harder to claim. Industry standards call for notification within five business days of discovering the problem, and the damaged freight should stay in the same condition and location where it was found until the carrier inspects it. Missing that window doesn’t automatically bar a claim, but it shifts the evidentiary burden heavily against you. Timestamped photographs of the damage are the single most useful piece of evidence in concealed damage disputes.
Where Common Carrier Rules Do Not Reach
The common carrier concept extends beyond physical transportation. Title II of the Communications Act imposes common-carrier-style obligations on qualifying communications providers, requiring just and reasonable charges and prohibiting unjust discrimination.3Office of the Law Revision Counsel. 47 USC 201 – Service and Charges Traditional telephone companies have long operated under these rules, and commercial mobile radio services (essentially cellular voice providers) must comply with key Title II provisions.9eCFR. 47 CFR 20.15 – Requirements Under Title II of the Communications Act
Broadband internet is a different matter. As of 2026, broadband internet providers are not subject to common carrier obligations under federal law, following the Sixth Circuit’s January 2025 decision that broadband is an “information service” rather than a “telecommunications service.”10United States Court of Appeals for the Sixth Circuit. In Re MCP No. 185 – Federal Communications Commission The court also held that mobile broadband does not qualify as a “commercial mobile service” and cannot be regulated as a common carrier on that basis. If you are looking at a dispute with an internet service provider, the common carrier duties described above are not the framework that governs it.