The information in a BOM comes from several different sources. It evolves over time, and although information can be entered initially by one group, another group often changes it later. Information, particularly on materials and colors, is continuously updated and changed. As products are dropped, added, changed, and reprioritized, as well as produced in many development states, completing a BOM from start to finish occurs over an extended period of time. It is crucial to have an awareness of these changes, as well as the reason and initiator of those changes. Access to creating and editing BOMs may be limited to specific groups and based on various development stages of a product.

The Design team is the first to generate the information that populates a BOM, and is also responsible for entering the materials and trim that make up the “look” of the product. Design works on many products simultaneously. Several of these products may be produced in the same fabric, or are part of the same collection that is marketed together. Since these groups of products often have the same theme, much of the trim, packaging, and labeling are similar or identical among products.

Components may be entered directly into a BOM, but oftentimes, they are listed individually, or on trim sheets with related products. Trim sheets and other forms are used to standardize color and trim selections across products (to add a consistent “look” to related products). They are also used as a reference when creating the first samples. Although Design makes initial choices about trim and sources, other departments responsible for producing and costing the product may influence these choices.

Forms used to track fabrics and trims are commonly created using Excel, and are often circulated and shared through e-mail, common drives, or through distributed hard copies.

The Sample or Patternmaking teams also influence BOM entries.

The person creating the pattern or sample influences which linings or interlinings are suitable for the garment. He or she also influences material decisions, such as button size and count, zipper size, and shoulder pad size. Any components that are affected by pattern measurements or construction methods can also be affected during this stage. In a CMT costing scenario, this information may be entered in a Cutter’s Must, and it later populates portions of the BOM for a specific product.

Specification writers pull together all the functional aspects of fabric, lining, and trim components for a product, and enter them into a preliminary version of a BOM. The specification writer’s BOM for apparel is typically divided into sections for fabrics, trim, and packaging and labeling. For footwear, it may include upper, bottom, packing, and logos and decorations.

During this stage, selections are made for all components of a product and all colorways that a product is produced in. Many items are developed, or dyed to match (DTM). Other items (such as zippers, interlinings, and hem tape) are not developed, and color selections are instead based on supplier codes.

If a manufacturer is producing a product in five colors, and the product uses five colored trims, then they must make 25 color selections. Items and item colors need to be specified in terms common to both the manufacturer as well as the supplier. To organize this process, colorways are created. Very often, color selections cannot be made without physical swatches of shell fabrics, or color standards used to represent these colors. Colors that can be used are based on seasonal and group standards. Actual color samples or standards may trickle in individually, which means the BOM is continually being edited, and referred to for ordering materials.

Often, materials are added to a BOM before final supplier decisions are made. These items usually do not exist in any material library, but serve as placeholders until actual material and supplier information is obtained.

It is often necessary to track a great deal of information per component listed on the BOM. This information varies by company and by user roles. Information may be specific to the manufacturer, the supplier, the cost, or even the status or approval of materials, as well as the user group accessing or entering the information.

Although all items needed to build a product should be listed on a BOM, there are also special circumstances surrounding this requirement. In most cases, the manufacturer makes all material and trim selections and, although it may supply some materials listed on the BOM, it might expect the factory to order the others. Shell fabrics might be ordered by the manufacturer, while the remaining components might be ordered by the factory. Quotas and the logistics of shipping items back and forth can affect whether an item is supplied, or included, in the CMT or FOB cost. The BOM may even need to indicate whether components are supplied to the manufacturer or not.

Communication of placement of colors is often necessary in a BOM (such as “color blocking” in skiwear). Both tabular and visual information is needed.

These groups use the BOM to order materials and trim (this is often done by the factory or vendor). Purchase Orders are written based on the information in the BOM. Similar products may be grouped so components can be ordered for groups of styles. To obtain the best pricing for materials, bulk orders can be placed by aggregating the components of many styles or collections.

Sourcing and Costing also need to work with the BOM. Where a product is produced may depend on the materials type (delicate silk or heavy cotton), as well as where the fabric is coming from. Several products may be grouped together to be produced in the same factory. A common example would be products using the same fabric. Additionally, yields can be adjusted once the product is further along in development.

Costing and Accounting issue Letters of Credit to factories that manufacture their products. The materials listed in a BOM are a critical aspect of this process.

The Quality and Production teams for Agents and Factories use the BOM to ensure that the proper materials and trim are used by the assemblers on the finished product.

Customs Compliance uses the BOM to select the correct codes for importing products. Examples might be garment type, fabric or yarn content, yarn coarseness, and trim materials such as bone, leather, and metallics.