Product classification

HS code for Rheostats: 8533.40

Electrical resistors, variable, including rheostats and potentiometers (excluding heating).

Classification of rheostats under HS 8533.40

Rheostats are classified under HS code 8533.40. This code falls under Chapter 85, which covers electrical machinery and equipment. Heading 8533 is dedicated to electrical resistors, including both fixed and variable types. Subheading 8533.40 specifically addresses "Other variable resistors, including rheostats and potentiometers." A rheostat is a type of variable resistor used to control current by varying the resistance in a circuit without interrupting the flow of current. Unlike a potentiometer, which is often used as a voltage divider, a rheostat is typically used to control high-power devices like motors or heaters. The classification is based on the functional characteristics of the device as a variable resistor. The Harmonized System distinguishes between fixed resistors (8533.10 through 8533.29) and variable resistors (8533.31 through 8533.40). Since rheostats are designed to have their resistance adjusted manually or mechanically, they are excluded from the fixed resistor categories and placed in the variable resistor subheadings.

Covers
  • Wire-wound rheostats
  • Slide rheostats
  • Carbon film rheostats
  • Motor speed control rheostats
  • High-power industrial rheostats
Also under 8533.40
  • Bourns 3386 series cermet trimmers
  • ALPS RK09 series carbon pots
  • Vishay Sfernice P16 series
  • Honeywell RTY series rotary position sensors

Codes often confused with 8533.40

Common mistake. Rheostats are often confused with potentiometers, which are also in 8533.40, but the error usually occurs when they are classified as fixed resistors under 8533.21 or 8533.29. Fixed resistors do not allow for adjustment, whereas rheostats are inherently variable. Additionally, if the rheostat is part of a larger control assembly, it might be incorrectly classified under 8537, which covers boards, panels, and consoles for electric control. However, if the component is imported as an individual resistor, 8533.40 is the correct designation. Heating resistors are also excluded and belong in 8516.

8533.21Electrical resistors; fixed, for a power handling capacity not exceeding 20W (including rheostats and potentiometers but excluding heating resistors and carbon resistors)8533.29Electrical resistors; fixed, for a power handling capacity exceeding 20W (including rheostats and potentiometers but excluding heating resistors and carbon resistors)85.37Boards, panels, consoles, desks, cabinets, bases with apparatus of heading no. 8535, 8536 for electricity control and distribution, (other than switching apparatus of heading no. 8517)85.16Electric water, space, soil heaters; electro-thermic hair-dressing apparatus; hand dryers, irons; electro-thermic appliances for domestic purposes; electro heating resistors, not of heading no. 8545

Top exporters and importers of HS 853340 (the code used for rheostats), 2025

In 2025, the largest exporter of HS 853340 (the code used for rheostats) in UN Comtrade data was China, with 25% of world exports; the largest importer in UN Comtrade data was China, with 21% 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 853340, not only rheostats.

Top exporters 2025 · share of world exports

  1. 1 China $935M
  2. 2 Hong Kong $413M
  3. 3 United States $281M

World total: $3.7B Reported figures on UN Comtrade ↗

Top importers 2025 · share of world imports

  1. 1 China $784M
  2. 2 United States $403M
  3. 3 Hong Kong $339M

World total: $3.7B 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 codes for rheostats

Brazil splits HS 8533.40 into 7 NCM codes. Pick the one that matches your product:

Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.

Questions about rheostats

What is the HS code for Rheostats?

The HS code for Rheostats is 853340 (Electrical resistors; variable, including rheostats and potentiometers (excluding heating)). The HS code for rheostats is 8533.40, which covers variable resistors and potentiometers.

How do I classify Rheostats for customs?

Rheostats is classified under HS code 853340 — Electrical resistors; variable, including rheostats and potentiometers (excluding heating). This is a 6-digit subheading level code.

Is a dimmer switch classified as a rheostat?

While some older dimmer switches used rheostats, modern electronic dimmers are usually classified under 8536 or 8537 depending on their complexity and voltage.

Which countries are the top exporters of rheostats (HS 853340)?

In 2025, the top exporters of HS 853340 (the code used for rheostats) in UN Comtrade data were China ($935M, 25% of world exports), Hong Kong ($413M) and the United States ($281M). World exports came to about $3.7B, 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 rheostats (HS 853340)?

In 2025, the top importers of HS 853340 (the code used for rheostats) in UN Comtrade data were China ($784M, 21% of world imports), the United States ($403M) and Hong Kong ($339M). World imports came to about $3.7B, 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 Rheostats the same in all countries?

The base HS code 853340 for Rheostats 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 rheostats in Brazil?

Brazil splits HS 853340 into 7 NCM codes, so the right one for rheostats depends on the product's details: 8533.40.11 (Thermistors), 8533.40.12 (Varistors for 1,000 V or less), 8533.40.13 (Other varistors, over 1,000 V), 8533.40.19 (Other non-linear semiconductor resistors), 8533.40.91 (Carbon throttle position potentiometers), 8533.40.92 (Other carbon potentiometers), and more.