Material risk
“Material available” doesn't mean production can start: reading ERPNext stock for a work order
Why ERPNext can show enough stock for a work order while the operation still cannot start: projected vs actual quantity, reservations, source warehouse and timing.
By Nguyen Dac Manh Cang · Published by TaktSignal · · 5 min read
Short answer. In ERPNext, “available” can mean several different numbers: actual quantity in one warehouse, actual quantity across all warehouses, or projected quantity that already counts purchase orders and planned production. A work order can only start on material that is physically in (or can reach) its source warehouse, is not already promised to an earlier work order, has passed any inspection, and is there before the operation that needs it. Check those four things before treating “we have enough” as “we can start”.
The numbers that all look like “available”
| Number | Where you see it | What it really is |
|---|---|---|
| Actual Qty | Stock Balance, Stock Projected Qty, the item's stock levels | Physical stock recorded in one warehouse right now |
| Projected Qty | Stock Projected Qty, item dashboard | Actual + Planned + Requested + Ordered − Reserved − Reserved for Production − Reserved for Subcontracting − Reserved for Production Plan |
| Reserved Qty for Production | Stock Projected Qty | Raw material reserved by submitted Work Orders and not yet transferred to their work-in-progress warehouse |
| Available Qty at Source Warehouse | Work Order → Required Items (after saving) | Actual stock in the work order's source warehouse — not what is left after other work orders' reservations |
| Transferred Qty | Work Order → Required Items | What has already moved to the work-in-progress warehouse for this work order |
| BOM Stock Report quantity | BOM Stock Report / BOM Stock Analysis | Stock in the chosen warehouse compared with one BOM, ignoring other orders |
Each number is correct. They answer different questions, and the one that looks most reassuring is often the one that answers the wrong question.
Five reasons “available” is not “usable now”
1. Projected quantity counts supply that has not arrived
Projected quantity adds Ordered Qty (purchase orders not yet received), Planned Qty (work orders not yet finished) and Requested Qty (material requests). That is the right number for replenishment planning. For tomorrow's operation it overstates what you can use, especially when an open purchase order line is already past its date. See why an overdue line is a risk to chase, not coverage.
2. The stock is in the wrong warehouse
A work order consumes from its Source Warehouse. Stock in another store, at another site, or in a quality-hold or rejected-goods warehouse shows up in company-wide totals but cannot be used until someone moves it — and moving it takes time and a Stock Entry. When warehouse roles are not obvious from their names, it is easy to count stock that the line cannot reach.
3. It is already promised to an earlier work order
When a Work Order is submitted, ERPNext reserves its raw materials as Reserved Qty for Production, which lowers projected quantity. Actual Qty does not change until the material is transferred. Two planners looking at actual stock can both see enough for their own order. If you use Stock Reservation, check those entries too.
4. It arrives after the operation needs it
Coverage is a date question. Compare the purchase order line's Required By or expected date — or the supplier's confirmed date, if there is one — with the work order's Planned Start Date, or with the planned start of the specific operation if you transfer material against Job Cards. Material that arrives Thursday does not help an operation planned for Tuesday.
5. The record itself is behind the floor
Late Material Transfers, issues that were never posted, offcuts and scrap that were never recorded: the stock figure may be confidently wrong. That is a data-trust problem, covered in Stale ERP data creates false confidence.
A synthetic example
Synthetic demo scenario: illustrative numbers from a fictional plant. Not customer data. Monday afternoon.
Work order WO-B needs 500 zippers, Source Warehouse Line 2 Stores, planned to start Tuesday 08:00.
| Warehouse | Actual Qty | Notes |
|---|---|---|
| Main Stores | 700 | 600 reserved for production by WO-A, which starts Monday |
| Line 2 Stores | 150 | WO-B's source warehouse |
| QC Hold | 50 | Waiting for inspection |
| Total | 900 |
One open purchase order brings 1,000 more, expected Thursday.
- Stock Balance across warehouses: 900 on hand, need 500. Looks fine.
- Projected Qty in Main Stores: 700 + 1,000 − 600 = 1,100. Looks very fine.
- What WO-B can actually use by Tuesday 08:00: 150 in Line 2 Stores, plus the 100 in Main Stores not reserved for WO-A, if someone transfers them today. The 50 in QC Hold is not released; the purchase order arrives after the start.
Usable: 250 of 500. WO-B can start half its quantity, or its start moves to Thursday — and if a customer order depends on WO-B, so may that delivery. No document is wrong.
A pre-start check in ERPNext
For each work order planned to start in the next few days:
- Open the Work Order and read Required Items: required, transferred and Available Qty at Source Warehouse for each item.
- For any item that looks tight, run Stock Projected Qty filtered by item. Compare Actual Qty with Reserved Qty for Production: what is left for this order after earlier work orders?
- Run Stock Balance by warehouse for the item. Is the stock where this work order consumes from, or does it need a transfer?
- For anything still short, check open purchase order lines in Purchase Order Analysis and compare their dates with the work order's planned start.
- Check for pending Quality Inspections on recent receipts of the item.
- Decide: start in full, start partially, move a transfer, chase a supplier, or tell sales now.
Where TaktSignal fits
TaktSignal is designed to do this check continuously, for every open work order at once. Its material-shortage alert is raised when open work orders need more of a material than is usable in stock plus supply arriving in time. Stock in warehouses it cannot recognise is not counted as usable, and an unconfirmed arrival lowers the alert's confidence instead of quietly covering the gap. Each alert lists the documents and quantities behind it. Understanding alerts · Understanding Data Trust.
TaktSignal is a Community Alpha, read-only toward ERPNext and not yet validated in real factories. Try it against a staging or test copy of ERPNext.
FAQ
Why doesn't Available Qty at Source Warehouse match what I can use? It shows actual stock in that warehouse. Other submitted work orders may already have reserved part of it.
Should I plan from projected quantity? For replenishment, yes. For deciding whether an operation can start tomorrow, use actual, unreserved stock in the right warehouse plus supply that arrives before the operation.
Does ERPNext stop me submitting a work order without stock? Submitting reserves material; it does not require the material to be on hand. The shortage becomes visible when the material transfer or manufacture entry is attempted — usually on the day production should start.