How to Create a Multi-Level BOM in Soply

A multi-level bill of materials (BOM) fits a process in which base materials make a sub-assembly and a sales product consumes that sub-assembly. For example: wax + fragrance → scented wax blend → candle. Soply expands the relationships to calculate sub-assembly and product availability.

Create the base materials first

In Raw Materials, create the base items such as wax and fragrance. Set each unit, inventory source, and status. A BOM node must be a raw material already created in Soply; you cannot add a Shopify product variant directly as a sub-component node.

Create the sub-assembly

Add an app-managed material for the intermediate item. In Composition, enable This material has sub-components, choose the existing child materials, and enter how much of each is needed per unit of the parent. Save it. Soply calculates this composite material's available quantity from its children instead of asking you to enter its own opening stock.

For example, one kilogram of scented wax blend might require 0.9 kilogram of wax and 0.1 kilogram of fragrance. Enter quantities using each child's base unit. If the units differ, calculate the conversion yourself before entering usage; do not assume Soply can infer it.

Connect the finished product

Under the sub-assembly's Product Usage, bind the sales variant and enter how much of the sub-assembly one sale uses. If your process has another intermediate level, create that material and configure its direct children on its own page.

After saving, inspect Tree View and Flat BOM to check the path and expanded base-material quantities. The app prevents a material from containing itself or creating a cycle. If the configured nesting limit is reached, simplify the model or review the store's maximum BOM depth setting.

A recipe change can affect several variants. Read the impact confirmation before saving, then review calculated availability at each level. See the multi-level BOM calculation guide for a worked example.