What is BOM

What is BOM

BOM stands for Bill of Material. This is the minimum quantity of all Raw Materials required separately for producing unit quantity of the product. BOM helps planning department in Raw Material procurement

What is BOM in Inventory?

Understanding Bill of Materials (BOM) in inventory management is like having the blueprint to a perfectly executed recipe. Just as a chef needs a detailed list of ingredients and steps to create a dish, manufacturers need a BOM to efficiently produce their products. Let’s dive into what BOM is all about and why it’s so crucial in inventory management.

Understanding the Basics

Definition of BOM

So, what’s a BOM anyway? A Bill of Materials (BOM) is essentially a detailed list that outlines all the raw materials, components, and sub-assemblies required to construct, manufacture, or repair a product. Think of it as the master ingredient list for everything that goes into your final product. Without this list, it would be like trying to bake a cake without knowing what ingredients you need.

Importance of BOM

Why should you care about BOM? Well, BOM is like the backbone of your manufacturing process. It ensures that every single part needed for production is accounted for, reducing the chances of errors and production delays. Imagine building a house without knowing how many bricks or nails you need—it would be chaos! Similarly, a BOM brings order and efficiency, making sure everything is in place when needed.

Types of BOM

BOM isn’t a one-size-fits-all concept. There are different types of BOMs tailored for various purposes in the production process.

Engineering BOM

The Engineering BOM (EBOM) is focused on the design specifications of a product. It includes all the components required from an engineering perspective and is used during the product development phase. It’s like the architect’s blueprint before construction begins.

Manufacturing BOM

On the flip side, the Manufacturing BOM (MBOM) is all about the production process. It details every single component and material needed during manufacturing. Think of it as the construction crew’s detailed list, ensuring they have all the right tools and materials to build the house.

Sales BOM

Then there’s the Sales BOM, which outlines the products and components shipped to customers. It’s often used in scenarios where products are sold as kits or bundles. Imagine buying a flat-pack furniture set—you’d want a list of all parts included to ensure nothing is missing.

Usage in Inventory

Inventory Management

BOM plays a pivotal role in inventory management. By detailing all required materials, it helps maintain optimal inventory levels. This means you won’t end up with too much or too little stock, saving you from the headaches of overstocking or stockouts.

BOM and Supply Chain

In the grand scheme of the supply chain, BOM is a game-changer. It provides critical information needed for procurement, production scheduling, and logistics. It’s like having a GPS for your supply chain, guiding every step of the way to ensure everything runs smoothly.

Creating a BOM

Key Components

Creating a BOM isn’t as daunting as it might sound. A typical BOM includes several key components such as part numbers, descriptions, quantities, units of measure, and sourcing information for each item. These components help ensure that everyone involved in the production process is on the same page, reducing miscommunications and errors.

Steps to Create a BOM

Identify the Final Product: Start by clearly defining what the final product is. This sets the foundation for listing all necessary components.

List All Required Materials: Detail every raw material, part, and sub-assembly needed. Be thorough—missing out on even a small component can lead to production delays.

Define Quantities: Specify the exact quantities of each item required. This helps in precise inventory management and procurement.

Organize in a Hierarchical Structure: Arrange the components in a structured format, often in a hierarchical order from top-level assemblies to sub-components. This makes it easier to understand and manage.

Best Practices

Accuracy and Detail

Accuracy is paramount in a BOM. Ensure every component is listed correctly and in detail. This minimizes the risk of production errors and ensures a smooth manufacturing process. It’s like following a recipe to the letter to bake the perfect cake—missing an ingredient or step can ruin the whole thing.

Regular Updates

BOMs should be living documents, updated regularly to reflect changes in design, material availability, or production processes. An outdated BOM is like using an old map—it won’t get you to your destination efficiently. Regular updates ensure the BOM remains relevant and useful.

Benefits of BOM

Cost Efficiency

A well-maintained BOM is a boon for cost efficiency. By clearly listing all required materials and their costs, it aids in budgeting and cost control. It’s like having a detailed shopping list before going to the store—you know exactly what you need and how much it will cost, preventing overspending.

Time Management

BOMs save a significant amount of time in production planning and execution. With all necessary components and their specifications clearly listed, production teams can work more efficiently. It’s the difference between building a model with instructions versus winging it—one is faster and more reliable.

Error Reduction

A detailed BOM minimizes errors in production by ensuring all required components are accounted for and correctly specified. This reduces the chances of rework or delays due to missing parts. It’s like checking a packing list before a trip—ensuring you have everything you need prevents last-minute scrambles.

Challenges of BOM

Complexity Management

Managing BOMs can be complex, especially for products with numerous components and sub-assemblies. The more intricate the product, the more detailed the BOM needs to be, which can become overwhelming without proper organization and tools.

Data Maintenance

Keeping BOM data up-to-date and accurate is a significant challenge. This requires diligent management and regular verification to ensure all changes in design, materials, or processes are reflected. It’s like maintaining a garden—regular care and attention are essential for it to thrive.

Integration Issues

Integrating BOMs with other systems, like Enterprise Resource Planning (ERP) and Product Lifecycle Management (PLM), can pose difficulties. Seamless data flow and compatibility are crucial, yet often challenging to achieve. Think of it as ensuring different parts of a machine work together smoothly—any mismatch can cause problems.

How BOM helps in Planning

  • Sales department has future Sale Orders to be manufactured
  • Planning division has minimum quantity required for producing the products.
  • Inventory stock has details about available stock required for manufacturing the product
  • Purchase department has information about orders of required material in pipe line.
  • Planning department collects data from Sales and purchase departments
  • Planning department collects data for stage wise wastage from production departments and calculate net impact on production for those Raw Materials
  • Planning department calculate total Raw material required as

Requirement = BOM quantity – Inventory quantity – Pipeline quantity – Quantity pending for stocking + waste quantity

What BOM contains

  • Finish Good Name and Party Code
  • List of Items required to produce the Finish Good that contains
  • Item Code
  • Item Name
  • Unit of Measurement
  • Quantity required
  • Drawing No (If any)
  • Catalogue no (if any)
  • Supplier Code (If specific)
  • Weight (If any)
  • Rating (If any) – Electrical / Electronic material like Capacitor , Induction coil, register, fan etc
  • Current
  • Voltage
  • AC / DC
  • RPM
  • Dimensions (if any)
  • Length
  • Width
  • Height

If effective material planning is being done based on BOM and related analysis, organizations can save a very decent amount of fund that can be used in segments.

Our Take

In essence, a BOM is an essential tool in inventory management and production. It provides detailed information necessary for efficient manufacturing, cost control, and error reduction. Like the blueprint to a building or the recipe to a dish, a well-crafted BOM ensures everything runs smoothly, making the complex process of production manageable and efficient


What is the primary purpose of a BOM?

The primary purpose of a BOM is to ensure all necessary materials are available for production, aiding in inventory management and production planning. It acts as a comprehensive guide for manufacturing, detailing every component and material needed.

How often should a BOM be updated?

BOMs should be updated regularly, particularly when there are changes in design, materials, or production processes. Regular updates ensure that the BOM remains accurate and relevant, preventing potential production issues.

Can a BOM be used for service and repair?

Yes, a BOM is often used in service and repair to identify necessary components and assemblies. It helps service teams understand what parts are needed to fix or maintain a product, ensuring they have everything required for the job.

What is the difference between an engineering BOM and a manufacturing BOM?

An engineering BOM focuses on the design specifications of a product, detailing all components from an engineering perspective. In contrast, a manufacturing BOM is used in the production process, listing all materials and components required for manufacturing the product.

How does a BOM contribute to cost efficiency?

A BOM contributes to cost efficiency by providing a clear and detailed list of all required materials and their costs. This aids in budgeting, cost control, and financial planning, ensuring that resources are used effectively and wastage is minimized.