Every ship in Captain & Company has a hold measured in units, and a trade is refused the moment the load would exceed it. The numbers below are the ones the live server checks against. They come out of SHIP_CARGO_CAPACITY in the backend's trade service, not from a wiki or a patch note, so they are what the game will actually enforce when you press buy.
| Hull | Capacity, in units | How you get it |
|---|---|---|
| Raft | 5 | Free. Everyone has one. |
| Dinghy | 32 | Bought |
| Freeblade Sloop | 80 | Bought |
| Clockwork Brig | 160 | Bought |
| Wraith Brig | 200 | Bought |
Two entries in that table are easy to miss.
The Wraith Brig is not a round number by accident. It is the Clockwork Brig plus a quarter, floored, and that relationship has held through every retune: 160 times 1.25 is 200.
The raft is the only hull that did not grow when the others did. It sits at 5 deliberately. It is the free hull, and its smallness is the argument for buying a better one.
If the server cannot match your ship against that table, it falls back to a default capacity of 5, which is a raft's load. This matters more than it sounds. The match is done by substring, so a hull has to be listed before any more generic name it contains, and a ship added to the catalog without a matching entry silently sails with a raft's hold rather than raising an error.
This is the part most players work out the hard way. Doubloons in the hold are cargo. Every 250 aboard fills one unit, rounded up, so a 250 doubloon chest costs you exactly one unit of space and a 1,000 doubloon chest costs four.
The rounding is a ceiling, not a nearest. One doubloon occupies a whole unit.
A worked example on a Dinghy, which holds 32:
20,000 doubloons -> ceil(20000 / 250) = 80 unitsThat is two and a half times a Dinghy's entire hold, in coins alone, before a single crate of goods. It is the reason a profitable run can leave you unable to pick anything else up, and it is why hull size is an economic decision rather than a cosmetic one.
Worth being precise, because the two halves of the game behave differently.
The capacity check runs when you buy goods at an island, and when you load cargo in before setting sail. It does not run on loot picked up at sea. Combat rewards and chest pickups are not weighed against your hold, which is why a ship can come back heavier than its own stated capacity.
Delivery missions are more conservative again. They only ever offer quantities up to three quarters of your hold, so a mission cannot fill your ship to the brim and leave you no room to trade on the way.
Wraith Brig 200.
These figures are current as of 28 August 2026 and are quoted from the code running in production on that date. They are tuned between rounds, so treat the date as part of the number.