Product classification
HS code for Marine steam turbines: 8406.10
Turbines, steam and other vapour turbines, for marine propulsion.
Classification of marine steam turbines under HS 8406.10
Marine steam turbines are classified under HS code 8406.10. Heading 84.06 covers steam turbines and other vapor turbines. The classification system differentiates these turbines based on their primary application. Subheading 8406.10 is specifically designated for turbines used for marine propulsion. These machines convert the thermal energy of steam into mechanical work to drive the propulsion system of a ship. The classification is determined by the intended use and the specific design features that make the turbine suitable for marine environments, such as specialized bearings, casing designs, and integration with marine gearboxes. This distinguishes them from steam turbines used in land-based power plants for electricity generation, which are classified under subheadings 8406.81 or 8406.82 depending on their power output. Accurate classification requires technical specifications showing the turbine's rated power and its configuration for marine use. It is also important to distinguish these from gas turbines, which fall under heading 84.11. The presence of specialized marine features, such as reversing stages or specific lubrication systems for sea conditions, helps confirm the classification under 8406.10. The turbine may be imported as a single unit or as part of a complete propulsion set.
- Covers
- Main propulsion steam turbines for ships
- Steam turbines for naval vessels
- Vapor turbines for marine propulsion
- High-pressure marine turbine units
- Low-pressure marine turbine units
- Also under 8406.10
- GE Marine steam turbines
- Siemens Energy marine turbines
- Mitsubishi Heavy Industries marine propulsion systems
- Kawasaki Heavy Industries marine turbines
Codes often confused with 8406.10
Common mistake. Marine steam turbines are often confused with turbines used for electrical generation, which are classified under HS codes 8406.81 or 8406.82. They are also sometimes misclassified as gas turbines, which fall under heading 84.11, or as parts of boilers under heading 84.02.
Top exporters and importers of HS 840610 (the code used for marine steam turbines), 2025
In 2025, the largest exporter of HS 840610 (the code used for marine steam turbines) in UN Comtrade data was the United States, with 69% of world exports; the largest importer in UN Comtrade data was Finland, with 45% of world imports. Countries that did not report 2025 data are estimated from partner records, which can understate them.
Figures cover everything classified under HS 840610, not only marine steam turbines.
Top exporters 2025 · share of world exports
- 1 United States $8.5M 69% of world exports
- 2 Singapore $851K 6.9% of world exports
- 3 Faroe Islands* ~$818K 6.6% of world exports · partner records ↗
World total: $12M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 Finland $9.7M 45% of world imports
- 2 Singapore $4.4M 21% of world imports
- 3 Malaysia $1.9M 9.0% of world imports
World total: $21M Reported figures on UN Comtrade ↗
How these figures are built
109 countries reported 2025 trade to UN Comtrade in HS 2022, and their own totals are used. Countries marked * did not, so their figures add up what other countries recorded trading with them, and their exports are valued at buyers' CIF prices. Those estimates miss trade with other non-reporting countries, so they can be low, and a non-reporting country can rank higher than shown or be missing from the list. World totals add both and leave out trade between two non-reporting countries. Figures are in current US dollars; reported imports are mostly valued CIF and exports FOB, and exports include re-exports. The UN Comtrade links show the underlying records; they can also list a few reporters left out here (regional groups and older HS editions).
Source: UN Comtrade (United Nations Statistics Division), 2025 annual data.
Brazil NCM code for marine steam turbines
Brazil classifies marine steam turbines under NCM 8406.10.00: HS 8406.10 with 00 added.
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about marine steam turbines
What is the HS code for Marine steam turbines?
The HS code for Marine steam turbines is 840610 (Turbines; steam and other vapour turbines, for marine propulsion). The HS code for steam and other vapor turbines for marine propulsion is 8406.10.
How do I classify Marine steam turbines for customs?
Marine steam turbines is classified under HS code 840610 — Turbines; steam and other vapour turbines, for marine propulsion. This is a 6-digit subheading level code.
Does this code include the gearbox?
Generally, no. While the turbine is 8406.10, the reduction gears used in marine propulsion are typically classified under HS code 8483.40.
Which countries are the top exporters of marine steam turbines (HS 840610)?
In 2025, the top exporters of HS 840610 (the code used for marine steam turbines) in UN Comtrade data were the United States ($8.5M, 69% of world exports), Singapore ($851K) and the Faroe Islands (about $818K). World exports came to about $12M, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
Which countries are the top importers of marine steam turbines (HS 840610)?
In 2025, the top importers of HS 840610 (the code used for marine steam turbines) in UN Comtrade data were Finland ($9.7M, 45% of world imports), Singapore ($4.4M) and Malaysia ($1.9M). World imports came to about $21M, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
Is the HS code for Marine steam turbines the same in all countries?
The base HS code 840610 for Marine steam turbines is internationally standardized for the first 6 digits across 200+ countries. Individual countries may add additional digits for national tariff lines and specific classifications.
What is the NCM code for marine steam turbines in Brazil?
In Brazil, marine steam turbines (HS 840610) is classified under NCM 8406.10.00.