How to Prevent Hidden Stock Loss in Your Workshop
Hidden stock loss in workshops comes from parts used but not recorded, damaged or obsolete stock not written off, and weak links between job cards and inventory. You prevent it by issuing parts only against job cards, doing regular cycle counts, and using one system that ties jobs, parts, and invoices together so nothing slips through.
In this article
- Where workshop inventory actually goes (and why)
- How to make sure parts used on job cards are always recorded
- Best practices for cycle counts in a busy workshop
- Closing the gaps: one system, one process
Where does workshop inventory actually go?
Inventory "disappears" when parts are taken for a job but not logged, when staff use stock for internal use without a requisition, or when damaged/obsolete items are never written off. Each of these creates a gap between system quantity and real quantity. Fixing it starts with discipline: no part leaves the shelf without being issued to a job or an approved internal request.
| Cause | Fix |
|---|---|
| Parts taken for job but not logged | Issue parts only to job cards; no part without a job issue |
| Internal use without requisition | Require internal requisition or "consumption" transaction that hits inventory |
| Damaged or obsolete stock never written off | Regular write-offs with approval; adjust stock and document reason |
| Job card and invoice not linked | Invoice from job card so every part on the job is on the invoice |
How do I make sure parts used on job cards are always recorded?
Use a single workflow: parts are only issued from stock when they're added to a job card. The job card becomes the record of what was used. When the job is invoiced, those same parts flow onto the invoice. No duplicate data entry, no "forgot to add it." This is how automotive parts and construction businesses stop leakage—by making the job card the single source of truth for parts usage.
What's the best way to do cycle counts in a busy workshop?
Count in small zones (one bay or one cabinet) and do it when that area is not in peak use. Use barcode scanning so counts are fast and accurate. Reconcile variances immediately and adjust stock; then track why variances happened (wrong job issue, no job issue, damage) so you can fix the process.
Preventing hidden stock loss is about making every movement visible and tying it to a job or an approved adjustment. Once that's in place, your numbers and your shelves will align.