Dear Team,
When creating a Production Plan and clicking the “Get Sub Assembly Items” button with the “Consider Projected Qty in Calculation” checkbox enabled, the system generates a list of Sub Assembly Items where Qty to Order = 0.
This happens even when Projected Qty = 0, which contradicts the standard formula:
Qty to Order=Required Qty (BOM)−Projected Qty
Please investigate why the calculation is not populating the correct required quantities.
This is a known behavior that catches many people off guard. The “Consider Projected Qty in Calculation” checkbox does not simply use Projected Qty = 0 as you’d expect, here’s what’s actually happening.
What “Projected Qty” means in this context
ERPNext calculates Projected Qty as:
Projected Qty = Actual Qty + Ordered Qty + Planned Qty + Requested Qty - Reserved Qty - Reserved for Production - Reserved for Sub Contract
So even if your Actual Qty = 0, the Projected Qty can be positive (or even much higher) if there are open Purchase Orders, existing Work Orders, or Material Requests already in the system for those sub-assembly items. ERPNext considers these “incoming” quantities as already fulfilling the demand, hence Qty to Order = 0.
How to diagnose
Solutions
Option 1 - Uncheck “Consider Projected Qty”
If you want to order based purely on BOM required qty vs actual stock on hand, uncheck this option. The system will then use only Actual Qty in its calculation.
Option 2 - Cancel/close open orders
If the “incoming” orders are stale or shouldn’t count, close/cancel the relevant Purchase Orders or Work Orders so they no longer inflate the Projected Qty.
Option 3 - Use “Include Non Stock Items” carefully
Double-check whether any BOM components have incorrect warehouse settings that might be pulling phantom stock.
In short, the formula is working correctly, the issue is that Projected Qty ≥ Required Qty due to existing open orders already covering demand. Let us know what you see in the Stock Projected Qty report!