HS Code 73.18 – Screws, bolts, nuts, coach screws, screw hooks, rivets, cotters, cotter-pins, washers (including spring washers) and similar articles, of iron or steel

HS code 7318 is a 4-digit heading in the Harmonized System that covers: Screws, bolts, nuts, coach screws, screw hooks, rivets, cotters, cotter-pins, washers (including spring washers) and similar articles, of iron or steel. Heading 7318 encompasses an incredibly vast and critical category of fasteners and connecting elements made of iron or steel, including screws, bolts, nuts, coach screws, screw hooks, rivets, cotters, cotter-pins, and washers (including spring washers). This heading is fundamental to almost every manufacturing and construction sector globally. The scope is broad, covering standard and specialized threaded and unthreaded fasteners, all united by their iron or steel composition. It is crucial for trade compliance due to the sheer volume and variety of products, each potentially subject to different specifications, quality standards, and end-use applications. Key sub-categories often distinguish between machine screws, self-tapping screws, wood screws, carriage bolts, hex nuts, wing nuts, lock washers, flat washers, pop rivets, and solid rivets. The accurate classification within 7318 is paramount for determining applicable import duties, ensuring compliance with technical standards (e.g., ISO, DIN, ASTM), and managing supply chain logistics for industries ranging from automotive and aerospace to electronics, machinery, and infrastructure. As a core component of Chapter 73, this heading underscores the importance of material composition (iron or steel) as the primary classification criterion for articles of base metal. Its historical context reveals its enduring significance, evolving from basic blacksmithing to highly engineered components essential for modern industrial production and robust infrastructure.

Hex head bolts, carriage bolts, machine screws, self-tapping screws, wood screws, drywall screws, cap screws, lag screws, eye bolts, U-bolts, J-bolts, hex nuts, lock nuts, wing nuts, castle nuts, flange nuts, flat washers, spring washers, lock washers, cotter pins, split pins, solid rivets, blind rivets, pop rivets, threaded rods, stud bolts, grub screws, set screws

Misclassification under 7318 frequently occurs when fasteners are integrated into more complex items or when their material composition is overlooked. One common error is confusing specialized fasteners that are explicitly designed as parts of specific machines or vehicles. For instance, if a bolt is clearly identifiable as a part of a motor vehicle (e.g., a specific engine bolt), it might be classified under Chapter 87 ('Vehicles other than railway or tramway rolling-stock, and parts and accessories thereof') rather than 7318. Another mistake involves fasteners made of other base metals; for example, copper fasteners would fall under 7415, and aluminum fasteners under 7616. Lastly, certain items like threaded pipe fittings are often confused with fasteners but are correctly classified under 7307 ('Tube or pipe fittings (for example, couplings, elbows, sleeves), of iron or steel'), highlighting the importance of functional distinction.

In 2025, the top exporters of HS code 7318 in UN Comtrade data were China ($10.0B, 20% of world exports), Germany ($7.6B) and the United States ($5.6B). World exports came to about $51.1B, 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.

In 2025, the top importers of HS code 7318 in UN Comtrade data were the United States ($6.4B, 13% of world imports), Germany ($4.9B) and Mexico ($2.8B). World imports came to about $50.8B, 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.

HS code 7318 is a 4-digit heading under Chapter 73 of the Harmonized System. The first 2 digits (73) identify the chapter, and digits 3-4 (18) specify the heading. This code contains multiple 6-digit subheadings for precise product classification.