A bill of materials (BOM) is the recipe for one product: the components per batch, the operations, and any scrap or by-products.
Manufacturing → Bills of Material → New bill of materials:
- Product * — the finished item (an Inventory item).
- Batch size * — the quantity the recipe makes; component quantities are per batch.
- Revision, Status (Draft, Active, Archived), Routing.
- Costing basis — how component costs are estimated on the BOM: Valuation rate (current stock cost), Last purchase rate or Standard cost (the item's cost price).
- Default recipe — make this the BOM that work orders for the product pick by default.
- Made by — Us (work orders), or A subcontractor, from our components: then the Subcontractor (a vendor) and Their rate per unit, what they charge per unit of the product. A subcontract BOM has no routing; its components are what you send them (section 11.10).
- Components — one row per material: Component, Qty per batch, Unit, Scrap % (expected process loss), Issue from (the warehouse) and Buy (flag components that must be purchased rather than stocked).
- Scrap & by-products — Item, Qty per batch, Unit, Recovery rate (the value credited back) and whether it is a By-product.
- The cost panel shows Materials, Operations (from the routing's work centre rates and times), Scrap recovery and the resulting Cost per unit.
- Description and Internal notes.
Only an Active BOM can be used on a work order. Products with several BOMs (alternative recipes, revisions) pick the default unless you choose another on the order.