Product classification
HS code for Sewage sludge: 3825.20
Residual products of the chemical or allied industries, not elsewhere specified or included, sewage sludge.
Classification of sewage sludge under HS 3825.20
Sewage sludge is classified under HS code 3825.20. This classification falls under Chapter 38, which covers miscellaneous chemical products. Heading 3825 is specifically reserved for residual products of the chemical or allied industries, not elsewhere specified or included, as well as municipal waste, sewage sludge, and other wastes. Sewage sludge is defined as the accumulated solids settled from biological or chemical treatment of waste water. This includes grit, screenings, and various types of sludge derived from the treatment of urban or industrial effluents. The classification is strictly for waste products; if the sludge has been processed into a specific fertilizer with a guaranteed nutrient content, it may be classified elsewhere. However, in its raw or stabilized waste form, 3825.20 is the correct designation. This code was introduced to better track the international movement of waste materials for environmental and regulatory purposes.
- Covers
- Stabilized sewage sludge from municipal treatment plants
- Grit and screenings from wastewater treatment
- Primary and secondary sludge from effluent processing
- Digested sludge from anaerobic treatment
- Dewatered sewage sludge cakes
- Also under 3825.20
- Biosolids pellets used as fertilizer
- treated sludge applied to agricultural land
- sludge sent to waste-to-energy plants
- raw sewage sludge from municipal treatment facilities
Codes often confused with 3825.20
Common mistake. Sewage sludge is often confused with HS code 3101.00, which covers animal or vegetable fertilizers. While sludge may have fertilizing properties, it remains under 3825.20 unless it is specifically prepared as a fertilizer product. Another misclassification is 3825.10, which is for municipal waste. While sewage sludge is often a byproduct of municipal systems, it is explicitly separated into subheading 3825.20. Industrial chemical waste that does not originate from water treatment should be classified under 3825.41 through 3825.69.
Top exporters and importers of HS 382520 (the code used for sewage sludge), 2025
In 2025, the largest exporter of HS 382520 (the code used for sewage sludge) in UN Comtrade data was the Netherlands, with 30% of world exports; the largest importer in UN Comtrade data was the Netherlands, with 65% 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 382520, not only sewage sludge.
Top exporters 2025 · share of world exports
- 1 Netherlands $1.4M 30% of world exports
- 2 Portugal $791K 17% of world exports
- 3 Thailand $663K 15% of world exports
World total: $4.5M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 Netherlands $10.0M 65% of world imports
- 2 Spain $1.4M 9.0% of world imports
- 3 Germany $630K 4.1% of world imports
World total: $15M 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 sewage sludge
Brazil classifies sewage sludge under NCM 3825.20.00: HS 3825.20 with 00 added.
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about sewage sludge
What is the HS code for Sewage sludge?
The HS code for Sewage sludge is 382520 (Residual products of the chemical or allied industries, not elsewhere specified or included; sewage sludge). The specific HS code for sewage sludge is 3825.20.
How do I classify Sewage sludge for customs?
Sewage sludge is classified under HS code 382520 — Residual products of the chemical or allied industries, not elsewhere specified or included; sewage sludge. This is a 6-digit subheading level code.
Can sewage sludge be classified as a fertilizer?
Generally, no. Even if used on land, it is classified as waste under 3825.20. It would only be classified in Chapter 31 if it has been significantly processed and meets the criteria for manufactured fertilizers.
Which countries are the top exporters of sewage sludge (HS 382520)?
In 2025, the top exporters of HS 382520 (the code used for sewage sludge) in UN Comtrade data were the Netherlands ($1.4M, 30% of world exports), Portugal ($791K) and Thailand ($663K). World exports came to about $4.5M, 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 sewage sludge (HS 382520)?
In 2025, the top importers of HS 382520 (the code used for sewage sludge) in UN Comtrade data were the Netherlands ($10.0M, 65% of world imports), Spain ($1.4M) and Germany ($630K). World imports came to about $15M, 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 Sewage sludge the same in all countries?
The base HS code 382520 for Sewage sludge 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 sewage sludge in Brazil?
In Brazil, sewage sludge (HS 382520) is classified under NCM 3825.20.00.