Guides
How the U.S. Coast Guard decides what you can carry on a walk-on ferry
Walk-on ferry rules: how 46 CFR subchapter K and T, USCG screening at the gangway, and operator policies govern baggage, pets and bikes on US sailings.
What to take away
- Walk-on ferry rules in the U.S. come from two places: federal safety and security law, and each operator's own tariff, so the same duffel can be fine on one route and refused on another.
- 46 CFR subchapter K covers security, and 46 CFR subchapter T covers small passenger vessel construction and operation; together they set the floor, not the ceiling.
- USCG screening at the gangway is a security measure, not a baggage inspection, and it is usually looking for weapons, explosives and other dangerous items rather than your lunch.
- Baggage, pet and bike policies vary sharply by operator, with Washington State Ferries, the MBTA ferries and Casco Bay Lines each publishing different limits.
- You can challenge a screening decision, but the practical move is to know the rule before you reach the dock and to ask for a supervisor if you disagree.
- State and local rules fill gaps the federal rules leave open, especially for pets, bikes and lithium batteries.
What 46 CFR subchapter K and T actually cover on a walk-on sailing
When people ask what governs a walk-on ferry rules question, the honest answer is a stack of rules. At the bottom is 46 CFR subchapter T, which sets construction and operation standards for small passenger vessels under 100 gross tons.
The full text sits in the federal small passenger vessel standards, and it is the baseline that most U.S. walk-on ferries are built and run against.
Subchapter T is about the vessel, not your bag. It covers stability, lifesaving equipment, fire protection, means of escape, and the number of passengers a boat may carry. If a ferry is certified under subchapter T, that certificate is why the crew can tell you a deck is full and stop boarding.
Subchapter K is the security subchapter. It requires operators of certain vessels to have security plans, designate security officers, and conduct screening of passengers and carry-on items. That is the legal hook behind the bag check you see at some terminals.
Subchapter K does not apply to every ferry. Small, low-risk operations may fall outside its screening requirements, which is why a tiny island ferry may wave you aboard while a big commuter route runs every bag past a table.
You can find both subchapters in the eCFR titles index if you want the exact wording. The Coast Guard also appears in the eCFR agencies index, which is the fastest way to pull up current USCG rule text without hunting through titles.
One more layer: the Federal Maritime Commission governs ticketing and tariff practices for many passenger vessel operators. FMC rules are about your fare and your ticket terms, not your backpack, but they matter when an operator refuses boarding and you want a refund.
What subchapter T does not decide
Subchapter T will not tell you whether your cooler is allowed. It will not settle whether a dog can ride on the outside deck. Those are operator decisions, written into tariffs and posted policies, as long as they do not conflict with federal safety or accessibility law.
What subchapter K does not decide
Subchapter K will not tell you what a prohibited item is on a specific route. It requires a security regime, and the operator writes the list. That is why a pocket knife that passes on one system can be confiscated on another.
How USCG screening works at the gangway, and what it is looking for
USCG screening at the gangway is best understood as a security checkpoint, not a customs inspection. Crew or terminal staff may look into bags, ask you to open a cooler, or run a hand wand over a passenger. The goal is to keep weapons, explosives and incendiary devices off the vessel.
Screening is not universal. It is most common on routes that carry large numbers of passengers, serve major terminals, or operate near high-profile infrastructure. On a small seasonal ferry, screening may be nothing more than a crew member glancing at what you carry.
What screeners look for is fairly narrow. They are checking for items that could damage the vessel or hurt people, and for behavior that suggests a threat. They are not checking whether you paid the right fare, and they are usually not weighing your bag.
If you are asked to open a bag, you can ask why. The screener may not give a detailed answer, but you are entitled to know whether the issue is a prohibited item or a security concern.
Screening decisions are made at the dock, which means the appeal path is also at the dock. If a crew member refuses an item, ask for the terminal supervisor or the vessel's security officer. On larger systems, that person exists by rule.
Accessibility interacts with screening in ways riders notice. Passengers using mobility devices may be directed to a separate lane, and the accessible walk-on ferry routes article covers how those lanes work in practice.
Screening versus baggage policy
Screening can stop an item even if the operator's baggage policy allows it. A legal pocket knife is still a legal pocket knife, but a screener can refuse it if the security plan treats it as a risk. Baggage policy is about size and count; screening is about danger.
Screening versus ticketing
Ticketing is a commercial matter. If you are denied boarding for a security reason, the refund question runs through the operator's tariff and, in some cases, the FMC. Keep your ticket and ask for the denial in writing.
Baggage limits and prohibited items on named US walk-on routes
Baggage rules on U.S. walk-on ferries are set by the operator, and they differ enough that regular riders keep a mental map. The table below compares three named systems on the points that cause the most dock-side arguments.
| Operator | Typical walk-on baggage limit | Prohibited or restricted items | Notes |
|---|---|---|---|
| Washington State Ferries (WSF) | Two pieces of hand-carried baggage plus a personal item on most routes | Weapons, flammables, compressed gas, and items that block aisles | Walk-on boarding is standard at most terminals; riders should check WSF rider information for current terminal procedures |
| MBTA ferries (Boston harbor) | Carry-on sized bags; large luggage discouraged at peak commute times | Open containers, hazardous materials, and oversized carts | Bikes and pets have separate rules from baggage |
| Casco Bay Lines (Portland, Maine) | Baggage that one person can carry in one trip; freight has its own tariff | Flammables, firearms without notice, and items that endanger the vessel | Mailboat runs and freight runs have different limits from passenger runs |
Those limits are not federal. They come from each operator's tariff, which is why a bag that fits on Casco Bay Lines may be refused on a peak MBTA commuter sailing.
Prohibited items cluster into a few groups: weapons, explosives, flammables, compressed gases, and anything that could spill or leak. Some operators also restrict large coolers, folding carts and anything with wheels that could become a projectile in rough water.
A packing list helps more than a rulebook here. The walk-on ferry routes packing list article maps what actually fits the common limits, and it is worth reading before a first trip on an unfamiliar system.
If you carry something unusual, call the operator the day before. Terminal staff can tell you whether an item is allowed, and a phone call is cheaper than a refused boarding.
Alaska and Hawaii differences
Alaska Marine Highway System sailings can run for days, so baggage limits are more generous but storage is tighter. Hawaii routes are short, and operators tend to restrict what can be carried on deck in wind and spray.
Why the same item travels differently
A folding bike is baggage on one system and a vehicle on another. A dog is a pet on one route and a service animal on another. The label determines the fee, the deck and sometimes whether you board at all.
Pets, service animals and carriers: the rules that differ by operator
Pet policy is where walk-on ferry rules diverge most. Some operators allow leashed pets on outside decks only. Some require a carrier. Some ban pets from passenger cabins entirely. A few allow small pets in carriers in indoor areas.
Service animals are different, and federal law controls. Under the ADA service animal requirements, a service animal is a dog, or in some cases a miniature horse, trained to do work or perform tasks for a person with a disability. That definition overrides blanket pet bans on walk-on ferries.
What that means in practice: a service animal must be allowed in passenger areas where the public is allowed, and an operator cannot charge a pet fee for it. An operator may ask two questions, whether the animal is required because of a disability and what work or task it performs. It may not demand documentation or a demonstration.
Under the ADA, emotional support animals do not qualify as service animals. Operators may treat them as pets, which means carrier rules, deck restrictions and fees can apply.
On WSF, pets generally travel on the car deck or in designated areas, and service animals may accompany their handlers in passenger spaces. On the MBTA ferries, pet rules vary by route and season, and carriers are often required. Casco Bay Lines publishes its own pet policy, and the mailboat runs have different constraints from the passenger runs.
If you travel with a service animal, know the two questions and be ready to answer them. That is usually the whole interaction. If a crew member asks for paperwork, you can politely explain the ADA rule and ask for a supervisor.
Carriers and crates
Carrier rules are about safety, not preference. A carrier keeps a pet from bolting on a moving deck or in a crowded terminal. If an operator requires one, arriving without it usually means you do not board.
Deck access
Outdoor deck access for pets is common but not universal. Some vessels have no safe outdoor area for animals, and the operator will require the pet to stay in a carrier at a seat or in a vehicle.
Bikes, e-bikes and lithium batteries in the vehicle deck versus the rack
Bike rules split into two questions: where the bike goes, and what powers it. A standard bicycle is usually treated as carry-on baggage if you can walk it on and park it in a rack. An e-bike is often treated as a vehicle or a hazardous item because of its battery.
On WSF, bicycles are common on walk-on sailings and racks are provided at many terminals, but e-bike batteries face restrictions tied to fire risk. On the MBTA ferries, bikes are allowed on many sailings but capacity is limited, and peak commuter runs may refuse them.
Casco Bay Lines handles bikes on passenger runs with limits, and freight runs have separate handling.
Lithium batteries are the live issue. A battery that is damaged, swollen or homemade is a fire risk on any vessel, and crews are trained to refuse them. Many operators require e-bike batteries to be removed and carried separately, or refuse e-bikes entirely on certain sailings.
The vehicle deck is not a loophole. If your bike goes on the car deck, you usually cannot access it during the crossing, and the same battery rules apply. Some operators require e-bikes to be declared at the ticket window before boarding.
For photographers and riders carrying gear, the US ferry crossing article covers what is practical to carry on deck, including how to secure a bike and a bag on a moving vessel.
If you plan to bring an e-bike, call ahead and ask three questions: is the battery allowed, must it be removed, and is there a rack or a vehicle-deck space. The answers change by route and season.
Standard bikes
Standard bikes are usually the easy case. Walk them on, park them in the rack, and keep the aisle clear. Some systems charge a small bike fee, and some include it in the walk-on fare.
E-bikes and batteries
E-bikes are the hard case. Treat the battery as the item being screened, not the bike. A battery that fails a visual check will end your boarding regardless of the bike's condition.
Where state rules end and federal walk-on ferry rules begin
Federal rules set the safety and security floor. State and local rules fill in the rest, and they can be stricter. A state can require life jackets for children, set speed limits in a harbor, or regulate pets on public docks.
Federal accessibility law runs across all of it. The ADA applies to ferry terminals and vessels, which is why boarding ramps, gangways and assistance policies are not optional. Operators must provide accessible boarding, and riders can ask for it.
USCG rules apply on the water. The Coast Guard inspects vessels, enforces safety equipment requirements, and responds to incidents. The National Transportation Safety Board investigates serious accidents and issues recommendations that can change how operators run.
State ferry systems, such as WSF and the Alaska Marine Highway System, are state agencies, so their policies are a mix of state administrative code and federal requirements. Private operators, such as Casco Bay Lines, are governed by their tariffs plus the same federal floor.
The Federal Maritime Commission sits in the middle for ticketing and service terms on many routes. If you have a fare dispute or a denied boarding with a refund question, the FMC is one place to look.
NOAA tide and current data matters more than most riders expect. A low tide can change the gangway angle and slow boarding, and a strong current can cancel a sailing. Neither is a rule, but both decide whether the rule gets applied that day.
When state rules are stricter
A state can require a permit for a commercial bike tour group, limit alcohol on a public ferry, or ban smoking on open decks. Those rules stand as long as they do not conflict with federal safety or accessibility law.
When federal rules control
Service animal access, vessel safety equipment and security screening are federal domains. An operator cannot use a state or local rule to refuse a service animal that meets the ADA definition.
How to challenge a screening decision without missing the boat
The first rule of challenging a screening decision is timing. A ferry leaves on schedule whether or not you are on it, so the practical goal is to resolve the issue in minutes, not hours.
Start by asking what specifically is the problem. A screener who says "this item" can often be satisfied by a different packing arrangement, a carrier, or a checked bag. A screener who says "no" to a category is a different conversation.
If you disagree, ask for the terminal supervisor or the vessel's security officer. On systems operating under subchapter K, that role exists by rule, and the person can overrule a front-line decision or explain it.
If the decision stands and you miss the sailing, ask for the denial in writing. Note the time, the vessel, the item and the name or badge of the person who refused it. That record is what you need for a refund request or a complaint.
Complaints go to different places depending on the issue. Safety and security screening complaints go to the Coast Guard. Fare and service complaints on many routes go to the FMC. Accessibility complaints can go to the operator and to the relevant federal agency.
If you are a frequent walk-on rider, the better strategy is prevention. Keep a small bag that fits every operator's limit, carry a carrier for your pet, and check the battery rule before you leave home. The walk-on ferry routes suit article helps match your typical load to a route that will accept it.
A short checklist for the dock
- Know your operator's baggage limit before you pack.
- Check whether your route screens bags at the gangway.
- Carry a carrier if you travel with a pet that is not a service animal.
- Confirm the e-bike battery rule by phone if you plan to bring one.
- Keep your ticket and note the time if an item is refused.
- Ask for a supervisor if you believe the decision is wrong.
- Know the two ADA service animal questions and be ready to answer them.
If you have time before the sailing
Use it to call the operator. A five-minute call about a cooler, a dog or a battery prevents the dock-side argument entirely. Terminal staff would rather answer the question on the phone than at the gangway.
If you do not have time
Pack to the strictest common limit: one carry-on sized bag, a personal item, and nothing that looks like a weapon or a hazard. That combination boards almost everywhere.
Common questions
Do federal walk-on ferry rules set a baggage weight limit? No. Subchapter T sets vessel and safety standards, not a passenger bag weight. Weight and size limits come from each operator's tariff and posted policy.
Can a ferry refuse my service animal? No, if the animal meets the ADA definition of a service animal. An operator may ask the two permitted questions but cannot require documentation or charge a pet fee.
Are e-bikes allowed on U.S. walk-on ferries? It depends on the operator and the battery. Many systems allow standard bikes easily but restrict or refuse e-bike batteries because of fire risk, so call ahead.
Where do I complain about a screening decision? Start with the operator and ask for the decision in writing. Safety and security complaints go to the Coast Guard, and fare or service complaints on many routes go to the Federal Maritime Commission.
Does subchapter K apply to every ferry? No. It applies to vessels and operations that meet its thresholds. Small, low-risk ferries may not conduct formal screening, which is why policies differ by route.
Can I bring a cooler on a walk-on sailing? Often yes, if it is hand-carried and does not block an aisle. Some operators restrict large coolers at peak times, so check the tariff for your specific route.
