Maritime transportation cost breakdown: same frame as trucking, three differences

Maritime transportation uses the EXACT SAME ten-category frame and mindset as road freight - see the Freight transportation guide for the full structure (vessel leading, fuel next, deadhead cost included). This guide only covers the three items road freight doesn't have, to avoid repeating what's already written.

The costing unit: ONE TON-NAUTICAL-MILE (or TEU-nautical-mile for container cargo) - the maritime industry's standard unit, playing the same role ton-miles play on the road.

Three cost items specific to maritime

1. Bunker fuel - purchased very differently from road diesel

Ships buy fuel (bunkers) at ports along the route, at prices that swing widely by port and timing - unlike a trucking fleet fueling from its own depot. Divide total bunker cost for the voyage by ton-nautical-miles actually achieved, not a fixed bunker price applied to every voyage.

Where to get the number: the bunker delivery note from each port of call.

2. Port fees & pilotage - a category road freight doesn't have

Berthing fees, pilotage for guiding the vessel through the channel, tug assistance. Cost per specific port called at, not a blanket estimate - rates vary widely port to port.

3. Demurrage - the ship still costs money standing still

When a vessel waits for a berth to load or unload, daily charter cost (if chartered) or opportunity cost (if owned) accrues even though the ship isn't moving and isn't earning transport revenue. This is the maritime equivalent of a deadhead leg in road freight - a real cost that's easy to forget because it isn't tied to any voyage leg.

Everything else - identical to road freight

Vessel (equipment), labor (crew), consumables (mooring lines, anti-fouling hull paint - divided by replacement cycle the same way as tires), subcontracted capacity (chartering outside vessels), rework (re-delivery after an incident), packaging (container dunnage), overhead (P&I insurance, shipping agency fees) - apply the exact same logic described in the Freight transportation guide, just swap the unit from miles to nautical miles.