Product classification
HS code for Lag screws: 7318.11
Iron or steel, threaded coach screws.
Classification of lag screws under HS 7318.11
Lag screws, also known as coach screws, are classified under HS code 7318.11. This classification is determined by the General Rules for the Interpretation of the Harmonized System (GRI), specifically identifying articles of iron or steel. Within Chapter 73, heading 7318 covers screws, bolts, nuts, coach screws, screw hooks, rivets, cotters, cotter-pins, washers, and similar articles. Subheading 7318.11 is specifically reserved for threaded coach screws. These fasteners are characterized by their heavy-duty construction, typically featuring a hexagonal or square head and a sharp, pointed thread designed for high-torque applications in timber or masonry with an anchor. The classification depends on the physical characteristics of the screw, specifically its heavy-duty nature and the specific thread type intended for wood-to-wood or wood-to-metal connections without the use of a nut.
- Covers
- Hex-head lag screws
- Square-head coach screws
- Galvanized steel lag bolts
- Stainless steel coach screws
- Zinc-plated heavy-duty wood screws
- Also under 7318.11
- Simpson Strong-Tie lag screws
- GRK Fasteners RSS screws
- Spax PowerLags
- FastenMaster LedgerLoks
Codes often confused with 7318.11
Common mistake. Lag screws are frequently misclassified under HS code 7318.12, which covers other wood screws. While lag screws are used in wood, 7318.11 is the more specific heading for coach screws. They are also sometimes confused with 7318.15, which covers other screws and bolts. The distinction lies in the thread design and the intended application; 7318.15 usually refers to machine screws or bolts intended for use with a nut or a pre-tapped hole, whereas lag screws create their own mating thread in the substrate.
Top exporters and importers of HS 731811 (the code used for lag screws), 2025
In 2025, the largest exporter of HS 731811 (the code used for lag screws) in UN Comtrade data was China, with 17% of world exports; the largest importer in UN Comtrade data was Germany, with 8.1% 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 731811, not only lag screws.
Top exporters 2025 · share of world exports
- 1 China $45M 17% of world exports
- 2 Germany $44M 17% of world exports
- 3 Czechia $34M 13% of world exports
World total: $263M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 Germany $28M 8.1% of world imports
- 2 Italy $27M 7.9% of world imports
- 3 Hong Kong $26M 7.5% of world imports
World total: $341M 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 that did not report are estimated from what other countries recorded trading with them. 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 lag screws
Brazil classifies lag screws under NCM 7318.11.00: HS 7318.11 with 00 added.
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
EU Regulatory Requirements
This product falls under the Carbon Border Adjustment Mechanism (CBAM). Importers to the EU must declare embedded carbon emissions and purchase CBAM certificates.
Questions about lag screws
What is the HS code for Lag screws?
The HS code for Lag screws is 731811 (Iron or steel; threaded coach screws). The primary HS code for lag screws (coach screws) made of iron or steel is 7318.11.
How do I classify Lag screws for customs?
Lag screws is classified under HS code 731811 — Iron or steel; threaded coach screws. This is a 6-digit subheading level code.
How do lag screws differ from standard wood screws in classification?
Standard wood screws are generally smaller and classified under 7318.12, whereas lag screws are heavy-duty fasteners with specific head types (hex or square) and are explicitly named as coach screws under 7318.11.
Which countries are the top exporters of lag screws (HS 731811)?
In 2025, the top exporters of HS 731811 (the code used for lag screws) in UN Comtrade data were China ($45M, 17% of world exports), Germany ($44M) and Czechia ($34M). World exports came to about $263M, 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 lag screws (HS 731811)?
In 2025, the top importers of HS 731811 (the code used for lag screws) in UN Comtrade data were Germany ($28M, 8.1% of world imports), Italy ($27M) and Hong Kong ($26M). World imports came to about $341M, 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 Lag screws the same in all countries?
The base HS code 731811 for Lag screws 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 lag screws in Brazil?
In Brazil, lag screws (HS 731811) is classified under NCM 7318.11.00.