Level Code

A level code in manufacturing inventory planning, commonly called Low-Level Code (LLC), is a numeric field that identifies the lowest BOM level at which a component appears. MRP uses it to sequence requirement explosions, consolidating all dependent demand before netting stock and preventing duplicate planning across assemblies.

On the shop floor, low-level code controls the order in which dependent demand is calculated during an MRP explosion. When a shared raw material or subassembly sits at different depths in multiple product structures, the system assigns its deepest occurrence and waits until all higher-level parents have been exploded. This timing is what makes receiving release timing, raw-material reservation, kitting, picklist generation, and inventory pegging trustworthy: the planner sees the true net requirement only after every source of demand is known. In a discrete manufacturing environment with high variant assemblies, a stale LLC can cause material to be kitted too early or shortages to surface at line side. In warehousing, it also affects putaway and replenishment signals because stock is reserved against the correct demand horizon. Keeping the code recalculated after any engineering BOM change ensures the planning run stays accurate and exception messages remain meaningful.