What Is a Bill of Materials? Components, Purpose & Types

The resulting top-level BOM (item number) would include children; a mix of finished sub-assemblies, various parts and raw materials. In contrast, a single-level structure only consists of one level of children in components, assemblies and material. A Bill of Materials (BOM) is a comprehensive list of components, assemblies, and other materials required to construct, manufacture, or repair a product or service. It is a critical document in product management and user experience, as it provides a detailed overview of the product’s components and their relationships. A bill of materials (BOM) is a comprehensive list of all the materials, components, and subassemblies required to manufacture a product. A BOM essentially provides a structure for making a product repeatably every time, thereby introducing a basis for standardization in the production process.

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A BOM is a listing of the quantities of each of the materials used to manufacture a product. For instance, a computer system’s Sales BOM might list the main unit, monitor, keyboard, and software, each with its code, as they appear in a sales catalog. The Sales BOM is pivotal for the sales and distribution channels to manage what end-users receive. By providing a shared understanding of all components and resources required, it’s easier for teams to work together towards a common goal. Bills of materials serve as crucial blueprints guiding product creation, but their complexity can vary depending on the intended use. Two fundamental BOM structuring methods, BOM explosion and BOM flattening, stand at opposite ends of this spectrum.

The roots of the BOM can be traced back to the early days of industrial manufacturing, when the need for detailed documentation of parts became evident. This template is just one of the manufacturing templates for Word and Excel that are free on our site. You’ll find free templates for every phase of your project and many industries such as manufacturing and construction as well. Because of their names and other similarities, the bill of materials format can often be confused with a bill of quantities, a form with a similar name.

Engineering Bill of Materials (EBOM)

A BOM is typically organized into a hierarchical structure, with the top-level item being the product itself. The components of the product are then listed in descending order, with the lowest-level components being the most basic components. This hierarchical structure allows for easy tracking of the components and their relationships.

Engineering BOM

In multi-level BOMs, the top level acts as the parent item with the second level of one or more components that are blended or assembled acting as the child item. Like a single-level BOM, multi-level BOMs contain materials and quantities for producing a finished good. However, for complex manufactured products, a multi-level BOM may have several sub-levels that feed into the final top-level BOM. The bill of materials is resources and resources must be tracked in real time in order to make sure you’re nonaccrual experience method nae meeting manufacturing milestones.

The BOM has since become an essential tool in the manufacturing industry, and is used to ensure that all the necessary components are available for production. It is easy to assume that small manufacturing companies may not need structured and well-crafted BOMs because with their size and smaller product portfolio, they are well aware of all the parts and raw materials required. It is also easy to assume that because a product is simple or consists of only a small number of components (or a single component), BOMs are not necessary. This is made during the design phase of the project and is usually based on computer-aided design (CAD) or electronic design automation (EDA) tools.

Types of bills of materials

Additionally, a comprehensive BOM features BOM notes that convey essential instructions or comments related to the manufacturing or assembly of the product. This is true of all BOMs but is especially true for those BOMs tied to MRP/ERP software. Without accurate, in-depth data, the lower levels of the BOM may not “roll up” correctly or accurately to the single level. Missing data also degrades the capabilities of the software and makes its benefits less pronounced.

1. By providing a shared understanding of all components and resources required, it’s easier for teams to work together towards a common goal.
2. This is the high-level BOM that lists the materials required to manufacture or assemble the product.
3. The modular BOM structure provides the assemblies/sub-systems that can be selected to “configure” an end-item.
4. This template is just one of the manufacturing templates for Word and Excel that are free on our site.

From engineering BOMs to sales bills, each variant holds its distinct structure, content, and application. Each serves a unique purpose, reflecting different stages in the product lifecycle and catering to the specific needs of departments within an organization. Each BOM encapsulates several layers of information, starting with BOM Level identifiers that assign a unique number to each part, simplifying the assembly and ordering processes.

Product Loop

This free bill of materials template for Excel allows you to list down the materials, parts and components that are needed to manufacture a product, as well as their unit cost and total cost. It can be used for making both single-level and multi-level bill of materials. Therefore, the bill of materials can be your central record of everything needed to build your product. The BOM also can assist in planning and controlling inventory in order to avoid delays and waste.

The term Bill of Materials (BOM) has what is a tax deduction its origins in the manufacturing industry. It is a document that lists all the components, parts, and materials required to build a product. The BOM is used to track the cost of the product and to ensure that all the necessary components are available for production. Production routing is a document that determines the production order of an item, i.e. the sequence of operations that go into manufacturing an end product. In enterprise resource planning systems, the bill of materials and the production routing form a basis for production planning, cost accounting, and many other essential functions of a manufacturing business.

But all of those concerns are tied to the bill of materials, which collects the pieces that’ll be used to build the final product. A single-level BOM is a straightforward list that shows the final product and the parts needed to produce it. They work well for products with simple assembly, such as furniture manufacturing or basic electronics – a single-level BOM would work great for those chairs we were building earlier, for example. In addition to the number and name of the part, a BOM should include a description for each as well. The description should detail the part’s size, material, measurements, and other specifications.

The sales bill of materials differs from others on this list in that it details the finished product before it’s assembled in the sales phase. The finished product and components are separate items on a sales order and the parent is listed only as a sales item, not inventory. It shows what you need to have in stock and helps forecast orders to ensure they’re on hand when needed.