# Net Tonnage

*Last updated: 2026-06-26*

> Ship operators, port authorities, and customs bodies rely on Net Tonnage (NT) to measure a vessel's usable cargo or passenger space – it is the primary basis for port dues, canal tolls, and certain taxes.

Ship operators, port authorities, and customs bodies rely on Net Tonnage (NT) to measure a vessel's usable cargo or passenger space – it is the primary basis for port dues, canal tolls, and certain taxes. Whereas Gross Tonnage captures the total enclosed volume of a ship, NT deducts all spaces that serve no revenue-earning purpose: engine rooms, crew quarters, the wheelhouse, and bunker compartments. Calculation follows the International Convention on Tonnage Measurement of Ships (London, 1969), which prescribes uniform formulas across all flag states. A large container ship may therefore show a net tonnage figure well below its gross tonnage. For freight forwarders, NT is most relevant when estimating port costs or comparing route options where dues are levied on a tonnage basis, such as transits through the Suez Canal.

**Source:** [https://www.imo.org/en/OurWork/Safety/Pages/TonnageMeasurement.aspx](https://www.imo.org/en/OurWork/Safety/Pages/TonnageMeasurement.aspx)

## Quick Facts

| Property | Value |
|---|---|
| Term | Net Tonnage |
| Language | EN |
| Word count | 130 |
| Last updated | 2026-06-26 |
| Source | https://www.imo.org/en/OurWork/Safety/Pages/TonnageMeasurement.aspx |

---

*Logistics Glossary — Freight Academy: [https://www.freight-academy.com/en/glossary/net-tonnage](https://www.freight-academy.com/en/glossary/net-tonnage)*

*Markdown mirror: [https://www.freight-academy.com/api/md/glossary/en/net-tonnage](https://www.freight-academy.com/api/md/glossary/en/net-tonnage)*

*JSON summary: [https://www.freight-academy.com/api/v1/glossary/net-tonnage/llm-summary?lang=en](https://www.freight-academy.com/api/v1/glossary/net-tonnage/llm-summary?lang=en)*