HS Code for HFO-1234yf

HFO-1234yf (2,3,3,3-tetrafluoropropene) is classified under HS code 2903.51. This classification is distinct from HFCs because HFOs (hydrofluoroolefins) are unsaturated fluorinated derivatives of acyclic hydrocarbons. The term \"unsaturated\" refers to the presence of at least one double bond in the carbon chain, which distinguishes HFOs from saturated HFCs found in the 2903.4x series. Heading 2903 covers halogenated derivatives, and the 2022 HS nomenclature introduced subheading 2903.51 to specifically account for HFO-1234yf, HFO-1234ze, and HFO-1336mzz. These chemicals are increasingly used as low-GWP (Global Warming Potential) refrigerants. Classification under 2903.51 is mandatory for the pure substance, as it is specifically named in the Harmonized System legal notes. This ensures that customs authorities can distinguish these newer, more environmentally friendly gases from older fluorinated gases.

Products Included

• 2,3,3,3-tetrafluoropropene (HFO-1234yf)
• 1,3,3,3-tetrafluoropropene (HFO-1234ze)
• (Z)-1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336mzz)
• Pure HFO-1234yf used in mobile air conditioning (MAC) systems

Common Misclassification

HFO-1234yf is frequently misclassified under 2903.45 (tetrafluoroethanes) or 2903.49 (other saturated HFCs). This is a technical error because HFO-1234yf is a propene (three carbons with a double bond), not an ethane (two carbons, saturated). Another common error is classification under 3824.78. While many new refrigerants are mixtures (which belong in 3824), pure HFO-1234yf must be classified in Chapter 29.

FAQ

What is the HS code for HFO-1234yf?

The HS code for pure HFO-1234yf is 2903.51.

Why is HFO-1234yf not classified with HFC-134a?

HFC-134a is a saturated hydrocarbon (2903.45), whereas HFO-1234yf is an unsaturated hydrocarbon (2903.51). The double bond in HFO-1234yf changes its chemical classification and its HS code.