Chapter 84 covers nuclear reactors, boilers, machinery, mechanical appliances and their parts, and is one of the largest industrial product chapters in the HS classification. This chapter includes power machinery, pumps, fans, refrigeration equipment, machine tools, office equipment, automatic data processing equipment, etc. The core characteristic is that the goods have mechanical movement or energy conversion functions, rather than being purely electrical products (Chapter 85) or vehicles (Chapter 87). The chapter notes strictly define the scope of each heading to avoid overlap with chapters such as electrical machinery and vehicles. Heading 8407 covers spark-ignition or compression-ignition reciprocating or rotary piston internal combustion engines, including gasoline engines, diesel engines, etc. Under this heading, engines are further subdivided by engine type (reciprocating/rotary), ignition method (spark ignition/compression ignition), use (marine, vehicle, aviation, etc.) and displacement. Reciprocating engines with a displacement of ≤50cc are usually used for small tools, models, lawn mowers, mopeds, etc., and are the smallest displacement tier under heading 8407. First 2 digits 84: belongs to Chapter 84, representing machinery, mechanical appliances and parts, excluding electrical equipment of Chapter 85. Digits 3-4 07: heading 8407, specifically referring to reciprocating or rotary piston internal combustion engines, including spark-ignition and compression-ignition types. Digits 5-6 31: subheading 840731, further limited to reciprocating piston engines with a displacement not exceeding 50cc, and usually spark-ignition type. Note that subheadings are divided by displacement, and 840731 is the smallest displacement tier, different from 840732 (50-250cc), 840733 (250-1000cc), etc. The goods are reciprocating piston internal combustion engines with a displacement of ≤50cc, which conforms to the description of heading 8407, and the displacement falls within the scope of subheading 840731. They are not classified under 8408 (compression-ignition engines) because they are usually spark-ignition; not under 8501 (electric motors) because they are not electric; not under 8467 (hand tools) because the engine is an independent commodity rather than a complete tool; not under 8711 (motorcycles) because they are not installed on vehicles.
Chapter
Chapter 84 covers nuclear reactors, boilers, machinery, mechanical appliances and their parts, and is one of the largest industrial product chapters in the HS classification. This chapter includes power machinery, pumps, fans, refrigeration equipment, machine tools, office equipment, automatic data processing equipment, etc. The core characteristic is that the goods have mechanical movement or energy conversion functions, rather than being purely electrical products (Chapter 85) or vehicles (Chapter 87). The chapter notes strictly define the scope of each heading to avoid overlap with chapters such as electrical machinery and vehicles.
Heading
Heading 8407 covers spark-ignition or compression-ignition reciprocating or rotary piston internal combustion engines, including gasoline engines, diesel engines, etc. Under this heading, engines are further subdivided by engine type (reciprocating/rotary), ignition method (spark ignition/compression ignition), use (marine, vehicle, aviation, etc.) and displacement. Reciprocating engines with a displacement of ≤50cc are usually used for small tools, models, lawn mowers, mopeds, etc., and are the smallest displacement tier under heading 8407.
Digit Breakdown
First 2 digits 84: belongs to Chapter 84, representing machinery, mechanical appliances and parts, excluding electrical equipment of Chapter 85. Digits 3-4 07: heading 8407, specifically referring to reciprocating or rotary piston internal combustion engines, including spark-ignition and compression-ignition types. Digits 5-6 31: subheading 840731, further limited to reciprocating piston engines with a displacement not exceeding 50cc, and usually spark-ignition type. Note that subheadings are divided by displacement, and 840731 is the smallest displacement tier, different from 840732 (50-250cc), 840733 (250-1000cc), etc.
Classification Basis
The goods are reciprocating piston internal combustion engines with a displacement of ≤50cc, which conforms to the description of heading 8407, and the displacement falls within the scope of subheading 840731. They are not classified under 8408 (compression-ignition engines) because they are usually spark-ignition; not under 8501 (electric motors) because they are not electric; not under 8467 (hand tools) because the engine is an independent commodity rather than a complete tool; not under 8711 (motorcycles) because they are not installed on vehicles.
📝 Declaration Elements
Product name: Declare the specific name of the engine, such as "gasoline engine" or "reciprocating internal combustion engine", and it must be consistent with the actual goods. Brand: Fill in the brand or manufacturer name of the engine; if there is no brand, indicate "no brand". Model: Fill in the specific model or specification, such as "1E40F-5", to facilitate identification of displacement and technical parameters. Displacement: Specify the engine piston displacement in cc, which must be ≤50cc, such as "49cc". Ignition method: State whether it is spark ignition or compression ignition, usually spark ignition. Use: Fill in the final use of the engine, such as "for lawn mowers" or "for model cars". Power: Fill in the engine output power in kW or horsepower as an auxiliary parameter. Whether complete engine: State whether it is a complete engine or a part; complete engines are classified under 8407, and parts under 8409. Product name: gasoline engine; Brand: XX; Model: 1E40F-5; Displacement: 49cc; Ignition method: spark ignition; Use: for lawn mowers; Power: 1.2kW; Whether complete engine: complete engine. Remarks: reciprocating piston internal combustion engine, displacement ≤50cc. Declaring displacement as exceeding 50cc when it is actually ≤50cc, resulting in incorrect classification under 840732. Mistakenly declaring a compression-ignition engine as spark ignition, incorrectly classifying it under 8407 instead of 8408. Confusing complete engines with parts, classifying engine parts under 8407 instead of 8409.
Product name
Declare the specific name of the engine, such as "gasoline engine" or "reciprocating internal combustion engine", and it must be consistent with the actual goods.
⚠️ Writing "engine" or "motor" in general terms without distinguishing internal combustion engines from electric motors.
Brand
Fill in the brand or manufacturer name of the engine; if there is no brand, indicate "no brand".
⚠️ Mistakenly filling in the trader's name as the brand, or omitting the brand and causing classification disputes.
Model
Fill in the specific model or specification, such as "1E40F-5", to facilitate identification of displacement and technical parameters.
⚠️ Incomplete model entry or inconsistency with the actual goods, affecting customs inspection.
Displacement
Specify the engine piston displacement in cc, which must be ≤50cc, such as "49cc".
⚠️ Mistakenly writing the displacement unit as ml or L, or declaring a displacement exceeding 50cc and causing classification errors.
Ignition method
State whether it is spark ignition or compression ignition, usually spark ignition.
⚠️ Omitting the ignition method, which may lead to incorrect classification under 8408 compression-ignition engines.
Use
Fill in the final use of the engine, such as "for lawn mowers" or "for model cars".
⚠️ The use description is too broad, such as "for machinery", and cannot assist classification.
Power
Fill in the engine output power in kW or horsepower as an auxiliary parameter.
⚠️ Inconsistent power units, or contradiction with displacement logic.
Whether complete engine
State whether it is a complete engine or a part; complete engines are classified under 8407, and parts under 8409.
⚠️ Mistakenly declaring parts as complete engines, or vice versa, resulting in incorrect codes.
Declaring displacement as exceeding 50cc when it is actually ≤50cc, resulting in incorrect classification under 840732.
Mistakenly declaring a compression-ignition engine as spark ignition, incorrectly classifying it under 8407 instead of 8408.
Confusing complete engines with parts, classifying engine parts under 8407 instead of 8409.
🎯 Classification Logic
Core basis for classification: 1) The goods are reciprocating piston internal combustion engines, conforming to heading 8407; 2) The ignition method is spark ignition, excluding 8408 compression ignition; 3) The displacement is ≤50cc, falling within subheading 840731; 4) The engine is an independent commodity and is not assembled on a complete vehicle or tool. According to HS notes, 8407 includes engines used for vehicles, ships, and aircraft, but those with a displacement of ≤50cc are usually used for small equipment and need to be confirmed in combination with use. 840732 Reciprocating engines with displacement 50-250cc: The displacement range is different; 840732 is 50-250cc, while 840731 is ≤50cc. Displacement is the core distinguishing point and must be measured accurately. 8408 Compression-ignition piston internal combustion engines: The ignition method is different; 8408 is compression ignition (diesel engines), while 8407 is spark ignition (gasoline engines). The ignition method must be clearly stated at declaration. 8467 Hand tools: 8467 is complete hand tools, such as lawn mowers and chain saws; 8407 is the engine itself. If the engine and tool are imported as one unit, they should be classified under 8467. 8711 Motorcycles and cycles fitted with an auxiliary engine: 8711 is a complete vehicle, while 8407 is an engine. If the engine is already assembled on a vehicle, it is classified under 8711. 8501 Electric motors and generators: 8501 is electric, while 8407 is an internal combustion engine. The power source is different, and electric and fuel-powered types must be distinguished. Confirm that the engine is a reciprocating piston internal combustion engine. Confirm that the ignition method is spark ignition. Confirm that the displacement is ≤50cc and accurately measured. Confirm that the engine is an independent complete engine rather than a part. Confirm that it is not assembled on a complete vehicle or tool.
Basis
Core basis for classification: 1) The goods are reciprocating piston internal combustion engines, conforming to heading 8407; 2) The ignition method is spark ignition, excluding 8408 compression ignition; 3) The displacement is ≤50cc, falling within subheading 840731; 4) The engine is an independent commodity and is not assembled on a complete vehicle or tool. According to HS notes, 8407 includes engines used for vehicles, ships, and aircraft, but those with a displacement of ≤50cc are usually used for small equipment and need to be confirmed in combination with use.
Confused Codes：
840732 - Reciprocating engines with displacement 50-250cc
The displacement range is different; 840732 is 50-250cc, while 840731 is ≤50cc. Displacement is the core distinguishing point and must be measured accurately.
The ignition method is different; 8408 is compression ignition (diesel engines), while 8407 is spark ignition (gasoline engines). The ignition method must be clearly stated at declaration.
8467 - Hand tools
8467 is complete hand tools, such as lawn mowers and chain saws; 8407 is the engine itself. If the engine and tool are imported as one unit, they should be classified under 8467.
8711 - Motorcycles and cycles fitted with an auxiliary engine
8711 is a complete vehicle, while 8407 is an engine. If the engine is already assembled on a vehicle, it is classified under 8711.
8501 - Electric motors and generators
8501 is electric, while 8407 is an internal combustion engine. The power source is different, and electric and fuel-powered types must be distinguished.
Self-Check：
✓ Confirm that the engine is a reciprocating piston internal combustion engine.
✓ Confirm that the ignition method is spark ignition.
✓ Confirm that the displacement is ≤50cc and accurately measured.
✓ Confirm that the engine is an independent complete engine rather than a part.
✓ Confirm that it is not assembled on a complete vehicle or tool.
❓ FAQ
If the displacement is exactly 50cc, should it be classified under 840731 or 840732? The upper displacement limit of HS code 840731 is "not exceeding 50cc", that is, ≤50cc. Therefore, 50cc should be classified under 840731. If the displacement is 50.1cc, it is classified under 840732. At declaration, accurate measurement is required to avoid errors caused by rounding. How to distinguish spark-ignition and compression-ignition engines? Spark-ignition engines (gasoline engines) ignite the air-fuel mixture through a spark plug; compression-ignition engines (diesel engines) ignite by compression. Usually, small engines with a displacement of ≤50cc are mostly spark-ignition and are classified under 8407. If they are compression-ignition, even with small displacement, they should be classified under 8408. At declaration, an explanation of the ignition method must be provided. An engine used for a model car with a displacement of 49cc, is it classified under 840731? Yes. A gasoline engine for a model car with a displacement of ≤50cc, spark ignition, and reciprocating type conforms to 840731. However, if the model car is electric, it is classified under 8501. Note that the classification differs between the complete model car and the engine imported separately. When importing a complete lawn mower with an engine displacement of 49cc, which code should it be classified under? The complete lawn mower should be classified under 8467 (hand tools), not 8407. 8407 applies only to engines imported separately. If the engine is imported together with the lawn mower, it is classified as a complete machine. How are parts of engines under 840731 classified? Engine parts (such as pistons, crankshafts, cylinder blocks) should be classified under 8409, not 8407. 8407 includes only complete engines. If parts are imported together with engines, they must be declared separately. An engine with a displacement of ≤50cc used for a moped, is it classified under 840731 or 8711? If the engine is imported separately, it is classified under 840731; if it is already assembled on a complete moped, it is classified under 8711. A moped usually refers to a cycle fitted with an auxiliary engine, with a displacement of ≤50cc. The judgment should be based on the import state. Can the displacement unit be written as ml at declaration? Yes, but it is recommended to use cc (cubic centimeter) uniformly; 1cc=1ml. Customs declaration systems usually accept cc. If writing ml, ensure the numerical value is consistent to avoid classification errors caused by unit confusion. How to check the regulatory conditions and tax rates for 840731? They can be checked through the official website of the General Administration of Customs of China, the Single Window, or the Import and Export Tariff of the People's Republic of China. Tax rates may change, so the latest version shall prevail. Regulatory conditions may include import licenses, CCC certification, etc., depending on use and origin.
Q: If the displacement is exactly 50cc, should it be classified under 840731 or 840732?
A: The upper displacement limit of HS code 840731 is "not exceeding 50cc", that is, ≤50cc. Therefore, 50cc should be classified under 840731. If the displacement is 50.1cc, it is classified under 840732. At declaration, accurate measurement is required to avoid errors caused by rounding.
Q: How to distinguish spark-ignition and compression-ignition engines?
A: Spark-ignition engines (gasoline engines) ignite the air-fuel mixture through a spark plug; compression-ignition engines (diesel engines) ignite by compression. Usually, small engines with a displacement of ≤50cc are mostly spark-ignition and are classified under 8407. If they are compression-ignition, even with small displacement, they should be classified under 8408. At declaration, an explanation of the ignition method must be provided.
Q: An engine used for a model car with a displacement of 49cc, is it classified under 840731?
A: Yes. A gasoline engine for a model car with a displacement of ≤50cc, spark ignition, and reciprocating type conforms to 840731. However, if the model car is electric, it is classified under 8501. Note that the classification differs between the complete model car and the engine imported separately.
Q: When importing a complete lawn mower with an engine displacement of 49cc, which code should it be classified under?
A: The complete lawn mower should be classified under 8467 (hand tools), not 8407. 8407 applies only to engines imported separately. If the engine is imported together with the lawn mower, it is classified as a complete machine.
Q: How are parts of engines under 840731 classified?
A: Engine parts (such as pistons, crankshafts, cylinder blocks) should be classified under 8409, not 8407. 8407 includes only complete engines. If parts are imported together with engines, they must be declared separately.
Q: An engine with a displacement of ≤50cc used for a moped, is it classified under 840731 or 8711?
A: If the engine is imported separately, it is classified under 840731; if it is already assembled on a complete moped, it is classified under 8711. A moped usually refers to a cycle fitted with an auxiliary engine, with a displacement of ≤50cc. The judgment should be based on the import state.
Q: Can the displacement unit be written as ml at declaration?
A: Yes, but it is recommended to use cc (cubic centimeter) uniformly; 1cc=1ml. Customs declaration systems usually accept cc. If writing ml, ensure the numerical value is consistent to avoid classification errors caused by unit confusion.
Q: How to check the regulatory conditions and tax rates for 840731?
A: They can be checked through the official website of the General Administration of Customs of China, the Single Window, or the Import and Export Tariff of the People's Republic of China. Tax rates may change, so the latest version shall prevail. Regulatory conditions may include import licenses, CCC certification, etc., depending on use and origin.
⚠️ Disclaimer: HS code classification, declaration elements, tariff rates and regulatory conditions on this page are for reference only and do not constitute legal advice on customs classification. Tariff rates and regulations are subject to change; the latest announcements from the General Administration of Customs and on-site determinations shall prevail. Please consult professional customs brokers or customs authorities before import/export.