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Dictionary / Bill of materials (BOM)

Bill of materials (BOM)

Last updated August 16, 2023

What does BOM mean?

A Bill of Materials (BOM) is a comprehensive list of components, parts, raw materials, and assemblies required to manufacture or assemble a finished product. It serves as a structured inventory of all the items needed to produce a specific product.

What does a BOM consist of?

A BOM typically includes the following information for each item:

  • Item Number or Code: A unique identifier for each component or part in the BOM.
  • Description: A brief description of the component or part.
  • Quantity: The quantity of each component needed to assemble one unit of the final product.
  • Unit of Measure: The measurement unit used for each component (e.g., pieces, kilograms, meters).
  • Part of Component Number: The manufacturer’s part number or reference code for each component.
  • Reference Designators: Identifiers that show where each component is used on the product’s design or schematic.
  • Supplier information: Details about the preferred suppliers for each component, including contact information and pricing.
  • Notes: Any additional information or instructions related to the component.

What are the types of BOMs?

There are different types of BOMs

  • Single-Level BOM: Lists components directly used in the final product
  • Multi-Level BOM: Includes all levels of sub-assemblies and components
  • Indented BOM: Represents the hierarchical structure of sub-assemblies and components
  • Flat BOM: Lists all components at a single level, disregarding sub-assembly relationship