HS Code for Temperature Sensors

Temperature sensors sit in chapter 90 of the HTSUS, and the branching factor is what the device does. A device that only measures or indicates temperature (a thermometer, pyrometer or infrared sensor) points toward heading 9025, the provision for hydrometers, thermometers, pyrometers and similar instruments. A device that automatically regulates or controls temperature, such as a thermostat, points instead toward heading 9032, the provision for automatic regulating or controlling instruments. General rates are low, from Free for pyrometers and infrared thermometers up to a few percent for other instruments and controls. Confirming whether the sensor measures only, or measures and controls, is the first step in exploring the most appropriate heading.

Temperature sensors live in chapter 90 of the HTSUS, the chapter for measuring, checking and precision instruments, and the first branch is functional: does the device simply measure temperature, or does it automatically regulate or control it? That distinction separates heading 9025 from heading 9032 and is the most important question to settle.

A device whose job is to measure or indicate temperature points toward heading 9025, which provides for hydrometers, thermometers, pyrometers, hygrometers and similar instruments. Within it, thermometers and pyrometers point toward subheading 9025.19, pyrometers at 9025.19.40 and infrared (non-contact) thermometers at 9025.19.80, while the residual 'other instruments' subheading 9025.80 gathers a range of related devices, including the electrical temperature-measuring line at 9025.80.10, along with sibling lines for barometers, hydrometers, hygrometers and recording instruments such as thermographs. An electrical temperature probe or sensor that measures and outputs a reading is typically explored within these 9025 lines.

A device that automatically regulates or controls temperature (acting on a valve, heater or circuit to hold a set point) points instead toward heading 9032, the provision for automatic regulating or controlling instruments and apparatus. Thermostats point toward subheading 9032.10, with a line for wall-mounted thermostats at 9032.10.00, while other automatic controls point toward the residual subheading 9032.89, with breakouts for low-voltage (6, 12 or 24 V) systems, other controls, and complete systems. The presence of an automatic control function, not just a sensing element, is what moves the device from 9025 to 9032.

A practical approach is to confirm the function first (measuring only, or measuring and controlling), then, within 9025, whether the instrument is a thermometer/pyrometer or one of the 'other instruments,' and within 9032 whether it is a thermostat or another automatic control. That sequence points toward a single most-appropriate heading to explore. It is generally better to use the specific instrument headings 9025 and 9032 than to reach for parts provisions or broad electrical-apparatus catch-alls; a bare thermistor or sensing element sold as a component may point toward a parts line instead, so the state of the article is worth confirming.

Duty treatment for temperature sensors is low across chapter 90. Measuring instruments under heading 9025 range from Free for pyrometers (9025.19.40) and infrared thermometers (9025.19.80) up to around 2.9% for hydrometers, with the electrical temperature-measuring line and most other 9025.80 lines running roughly 1% to 1.7%. Automatic regulating and controlling instruments under heading 9032 run roughly 1.1% to 1.7%, including wall-mounted thermostats and the other automatic-control lines. Because the rates are modest and cluster closely, the main reason to identify the right heading is better classification (measuring versus controlling) rather than a large duty difference. Preferential rates under free trade agreements or programs such as the Generalized System of Preferences may reduce or eliminate duties for qualifying origins. These figures are estimates for general planning purposes only.