Product classification
HS code for Automatic resistance welder: 8515.21
Welding machines and apparatus, for resistance welding of metal, fully or partly automatic, whether or not capable of cutting.
Classification of automatic resistance welder under HS 8515.21
Automatic resistance welders are classified under HS code 851521 due to their primary function and operational characteristics. This classification specifically covers welding machines and apparatus designed for resistance welding of metal, which operate either fully or partly automatically. The description further clarifies that these machines may or may not possess the capability for cutting. The core criteria for this classification are the resistance welding technology employed, the automatic or semi-automatic nature of their operation, and their application in processing metal components.
- Covers
- Automatic spot welding machines
- Automatic seam welding machines
- Automatic projection welding machines
- Automatic flash butt welding machines
- Robotic resistance welding cells
- Also under 8515.21
- KUKA robotic welding systems
- FANUC resistance welding robots
- Fronius DeltaSpot welders
- ARO Technologies automatic welders
Codes often confused with 8515.21
Common mistake. A common misclassification occurs with HS code 851531, which covers arc welding machines that are fully or partly automatic. The distinction lies in the welding principle: 851521 is for resistance welding, while 851531 is for arc welding. Another point of confusion can be with 851529, which covers other resistance welding machines that are not automatic. The key differentiator for 851521 is the explicit requirement for fully or partly automatic operation, distinguishing it from manual or semi-automatic resistance welders that lack automated control.
Top exporters and importers of HS 851521 (the code used for automatic resistance welder), 2025
In 2025, the largest exporter of HS 851521 (the code used for automatic resistance welder) in UN Comtrade data was China, with 23% of world exports; the largest importer in UN Comtrade data was the United States, with 20% 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 851521, not only automatic resistance welder.
Top exporters 2025 · share of world exports
- 1 China $331M 23% of world exports
- 2 Germany $251M 17% of world exports
- 3 Italy $142M 9.8% of world exports
World total: $1.5B Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 United States $266M 20% of world imports
- 2 Mexico $140M 10% of world imports
- 3 India $85M 6.3% of world imports
World total: $1.3B 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 automatic resistance welder
Brazil classifies automatic resistance welder under NCM 8515.21.00: HS 8515.21 with 00 added.
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about automatic resistance welder
What is the HS code for Automatic resistance welder?
The HS code for Automatic resistance welder is 851521 (Welding machines and apparatus; for resistance welding of metal, fully or partly automatic, whether or not capable of cutting). The HS code for an automatic resistance welder is 851521. This code specifically applies to machines designed for resistance welding of metal, operating either fully or partly automatically, and may include cutting capabilities.
How do I classify Automatic resistance welder for customs?
Automatic resistance welder is classified under HS code 851521 — Welding machines and apparatus; for resistance welding of metal, fully or partly automatic, whether or not capable of cutting. This is a 6-digit subheading level code.
What is the difference between resistance welding and arc welding machines?
Resistance welding machines (HS 851521) join metals by applying pressure and passing a high electric current through the workpieces, generating heat at the interface due to electrical resistance. Arc welding machines (HS 851531), conversely, use an electric arc to melt and fuse the metals, often with the addition of filler material. The fundamental difference lies in the heat generation mechanism and the presence or absence of an electric arc.
Which countries are the top exporters of automatic resistance welder (HS 851521)?
In 2025, the top exporters of HS 851521 (the code used for automatic resistance welder) in UN Comtrade data were China ($331M, 23% of world exports), Germany ($251M) and Italy ($142M). World exports came to about $1.5B, 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 automatic resistance welder (HS 851521)?
In 2025, the top importers of HS 851521 (the code used for automatic resistance welder) in UN Comtrade data were the United States ($266M, 20% of world imports), Mexico ($140M) and India ($85M). World imports came to about $1.3B, 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 Automatic resistance welder the same in all countries?
The base HS code 851521 for Automatic resistance welder 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 automatic resistance welder in Brazil?
In Brazil, automatic resistance welder (HS 851521) is classified under NCM 8515.21.00.