Boat Shipping Glossary

Maritime Transport & Hauling Terminology by Category

50 terms you'll actually run into when getting a boat transport quote — from beam and oversize permits to RoRo freight and cargo insurance.

Dimensions & Regulations

Beam

The width of a boat at its widest point. Critical for determining if a transport requires oversize load permits.

A shipment that exceeds a state's standard legal width, height, or length limits — for boats, this is triggered once beam exceeds 8.5 ft. Oversize loads require permits, and sometimes escort vehicles, in every state they cross.

Draft

How deep a boat's hull sits below the waterline. Relevant for in-water and RoRo transport, since it determines which marinas, ramps, and loading berths a vessel can use.

Freeboard

The height of a boat's hull above the waterline. Along with air draft, it factors into clearance calculations for bridges and low-hanging obstacles during in-water moves.

Air Draft

The total height of a boat from the waterline to its highest fixed point, including towers, antennas, and outriggers. Determines whether a route's bridges and power lines can be cleared without dismantling.

Height Pole

A pole mounted on a lead escort vehicle to physically check overhead clearance ahead of an oversize load, used when a loaded trailer approaches 13.5–14 ft.

Wide-Load Permit

A state-issued permit authorizing a vehicle and its cargo to travel at a width beyond the standard legal limit. Boat haulers typically need one per state once beam passes 8.5 ft, at roughly $50–$250 apiece.

Axle Weight

The portion of total load weight resting on each axle of the trailer. States cap axle weight independently of gross weight, which can force a heavier boat onto a trailer with more axles even if the total weight seems reasonable.

Gross Vehicle Weight (GVW)

The combined weight of the tow vehicle, trailer, and boat. Exceeding federal or state GVW thresholds can require additional permits and route restrictions beyond those triggered by width alone.

DOT Number

A unique identifier issued by the Federal Motor Carrier Safety Administration (FMCSA) to any commercial carrier operating across state lines. Always confirm a hauler's DOT number before booking.

FMCSA

The Federal Motor Carrier Safety Administration, the agency that regulates and licenses commercial trucking companies in the US, including boat haulers operating interstate.

MC Number

A Motor Carrier number issued by the FMCSA to carriers authorized to transport regulated freight for hire across state lines. Distinct from a DOT number, which every commercial vehicle needs.

Transport Methods & Equipment

Roll-on/Roll-off (RoRo)

A shipping method where the boat (usually on a trailer) is driven on and off the transport vessel. The most common way larger boats and yachts cross oceans.

Lift-on/Lift-off (LoLo)

An ocean freight method where the boat is lifted by crane onto and off the cargo ship, rather than driven aboard. Used when a port lacks RoRo ramps or the vessel can't be trailered.

Flat Rack Container

An open-sided shipping container with a flat base and collapsible end walls, used to ship boats too large for a standard container but that don't need a full RoRo berth.

Break-Bulk Cargo

Freight shipped as an individual unit rather than in a container — the category most boats and yachts fall into for ocean freight, since they're loaded and secured on the vessel's deck or hold individually.

Lowboy Trailer

A semi-trailer with two drops in deck height, used to transport taller boats while avoiding bridge clearance issues.

Step-Deck Trailer

A trailer with a single drop in deck height behind the gooseneck, sitting lower than a standard flatbed but higher than a lowboy. A common middle-ground choice for mid-size boats.

Removable Gooseneck (RGN) Trailer

A hydraulic trailer whose front section detaches and lowers to the ground, allowing a boat on its own cradle or trailer to be driven or winched straight on without a crane.

In-Water Transport (Wet Tow)

Moving a boat under its own power or under tow between marinas, rather than trailering it overland. Typically about 15% cheaper than overland hauling but limited to boats that are seaworthy and can be crewed.

Dry Stack Storage

A storage system where smaller boats are racked indoors on shelving and launched by forklift, common at marinas that also handle transport drop-off and pickup.

Boat Cradle

A custom-built support frame that holds a boat's hull in place during transport or storage, distributing weight evenly to avoid stress cracks.

Blocking and Cribbing

Wood or synthetic supports placed under a boat's hull to keep it stable and evenly supported on a trailer or in dry storage.

Tie-Down Straps

Rated straps or chains used to secure a boat to its trailer or cradle, positioned to avoid damaging the hull while withstanding highway-speed forces.

Escort Vehicle (Pilot Car)

A vehicle that accompanies an oversize boat transport to ensure road safety and compliance with state regulations.

Costs & Fees

Fuel Surcharge

A variable add-on, typically about 8% of the base rate, that carriers apply to pass fluctuating diesel prices on to the customer instead of constantly reprinting rate sheets.

CBM (Cubic Meter)

The unit ocean freight carriers use to price RoRo and LoLo shipments — length × width × height of the boat in meters. Unlike overland trucking, international rates are usually quoted per CBM, not per mile.

Terminal Handling Charges (THC)

Fees a port charges to move cargo on and off the dock and through the terminal, billed separately from the ocean freight rate. THC applies at both the origin and destination port on an international boat shipment.

Linear Foot Rate

A pricing method, mostly used in RoRo and flat-rack quotes, that charges by the boat's length in feet or meters rather than by weight or per-mile distance.

Deadhead Miles

The distance a carrier's truck has to drive empty to reach your pickup location or after dropping off your boat. Remote pickup points can raise a quote because the carrier prices in this unpaid mileage.

Accessorial Fees

Extra charges beyond the base transport rate — things like winching, extra labor for tight access, storage while waiting on a connecting leg, or after-hours pickup.

Permit Fee

The cost of the oversize or overweight load permit a state charges per trip, typically $50–$250 per state crossed for a wide-beam boat.

Preparation

Shrink-wrap

A plastic cover tightly sealed over a boat to protect it from weather and debris during overland or sea transport.

Winterizing

Draining water systems and adding antifreeze to a boat's engine and plumbing before it travels through or sits in freezing temperatures, preventing cracked blocks and burst lines.

Mast Unstepping

Removing a sailboat's mast before transport, usually required for overland hauling and container shipping where height or container dimensions won't allow it to stay stepped.

Haul-Out

Lifting a boat out of the water, typically with a travel lift or crane, so it can be placed on a trailer or into storage ahead of transport.

Splash (Relaunch)

Lowering a boat back into the water at the end of a haul-out or transport, the counterpart to hauling out.

Commissioning

Reversing winterization and prep work after transport — reinstalling batteries, rigging the mast, and checking systems before a boat goes back in the water.

Booking & Insurance

Freight Broker

A company that doesn't own trucks itself but posts your shipment to a load board and matches you with an independent carrier. Most boat transport listings online are brokers, not carriers.

Owner-Operator Carrier

A carrier who owns their truck and trailer and drives the load themselves, rather than dispatching it through a broker. Booking direct with a carrier can cut out the broker's markup.

Central Dispatch

A load board where brokers and shippers post transport jobs and carriers bid on them — the main marketplace boat and vehicle haulers use to find work.

Certificate of Insurance (COI)

A document from a carrier's insurer confirming their cargo insurance coverage and policy limits. Always request one directly from the agent, not just from the carrier, before handing over your boat.

Cargo Insurance

Insurance a carrier holds specifically to cover freight while in transit. A personal boat insurance policy typically does not cover damage caused by a third-party hauler — that's the carrier's cargo policy's job.

Bill of Lading (BOL)

The legal document a carrier signs at pickup and delivery recording the boat's condition, confirming the shipment, and serving as the basis for any damage claim.