Fashion BOM Guide: How to Create a Bill of Materials for Garments
Complete guide to creating a garment bill of materials (BOM) — what to include, how to organize materials, and how AI generates BOMs automatically.
What is a BOM in fashion
A bill of materials (BOM) is a complete list of every material used in a garment — from the primary shell fabric to the smallest thread. It tells your manufacturer exactly what to source and how much of each material is needed.
A production-ready BOM includes material names, compositions, weights, colors, color codes, supplier references, and placement (which part of the garment each material is used in). Missing or inaccurate BOM entries cause sourcing delays and production errors.
Standard BOM categories
A garment BOM is typically organized into material categories for clarity.
- Shell fabrics: primary body fabric with composition, weight, width, color
- Lining fabrics: interior lining with composition and weight
- Interlining/fusing: fusible or sew-in interfacing with weight and placement
- Trims: ribbing, elastic, drawcords, bias tape, piping
- Thread: sewing thread type, count, color for each seam type
- Hardware: zippers, buttons, snaps, eyelets, buckles with size and finish
- Labels: main label, care label, size label — material, size, and content
- Packaging: hangtags, polybags, tissue, hangers
How AI generates garment BOMs
AI tech pack generators populate BOMs based on garment type and construction details. When you describe a heavyweight cotton hoodie with a YKK zipper, the AI generates appropriate entries for cotton fleece shell, ribbing for cuffs and hem, matching thread, YKK zipper with specific type, drawcord, eyelets, and care labels.
The AI understands material relationships — a navy garment gets navy thread, navy ribbing, and tonal hardware. A garment targeting the US market gets FTC-compliant care label specifications.
BOM accuracy and supplier specifics
AI-generated BOMs provide structurally accurate material specifications — correct categories, appropriate compositions, and consistent colors. However, specific supplier references (your preferred fabric mill, your zipper supplier's part numbers) need to be added manually.
Use the AI chat to update supplier-specific details: 'change shell fabric to our supplier code F-2847' or 'specify YKK 5VS #580 for main zipper'. These edits update the BOM while maintaining consistency with other tech pack sections.
Common BOM mistakes that delay production
Missing thread specifications are the most common BOM error — manufacturers need to know thread type, color, and count for each seam type. Missing hardware specifications (zipper model, button size, snap type) force the manufacturer to guess or ask, delaying production.
Another common mistake is inconsistent colors between BOM entries and colorway definitions. If your colorway says navy but your BOM says black thread, the manufacturer has a conflict to resolve. AI-generated BOMs avoid this by deriving all color entries from the same colorway data.