What a stock adjustment is
A stock adjustment is a document that corrects on-hand stock outside the normal receipt and issue flow — an adjust-increase where physical stock exceeds the book, an adjust-decrease where the book exceeds physical. It exists for genuine corrections: reconciling a count variance, writing off damage or spillage, fixing a historical data error. Because it is a document rather than an edit, every adjustment updates the running stock balance at commit and writes its own row in the immutable stock ledger — dated, quantified, valued and attributable.
Adjustments occupy an awkward place in stock control: necessary, because no operation is error-free, and dangerous, because an undisciplined adjustment habit can hide theft, mask process failures and quietly falsify the valuation. The difference between the two outcomes is entirely a matter of mechanism and discipline — which is what this guide covers.
Documents, not edits — the core control
In Fast Inventory Software, adjustments ride the same document engine as every other movement. A goods receipt, a material issue and an adjustment are all documents of different types on one engine — which means an adjustment automatically inherits the properties that make movements trustworthy:
- A numbered document with header and lines, a user, a date and a status — referenceable from the count or incident that triggered it.
- A stock effect at commit — the balance changes when the document posts, not while someone is halfway through typing it.
- An immutable ledger row recording opening balance, transaction quantity, type, reference and rate, with a plus or minus effect. Nothing is edited in place; the ledger only ever grows.
- An audit record on the write — the platform logs before/after images on every database write, a second net under the ledger itself.
This is the same stock-commit principle the pillar guide describes — stock is a running balance changed only at documented commit points — applied to the correction path, where it matters most. See Stock Movements & Transactions for the engine itself.
Adjustment types — increase, decrease, scrap
| Document | What it does | Stock effect | Typical use |
|---|---|---|---|
| Adjust-increase (ADI) | Raises book stock to match reality | Increase | Count found more than book; historical under-recording |
| Adjust-decrease (ADD) | Lowers book stock to match reality | Decrease | Count found less than book; loss, spillage, evaporation |
| Scrap remove / add (SCR / SCA) | Posts scrap out of (or back into) stock as its own type | − / + | Damage and write-offs, kept distinct from plain corrections |
Keeping scrap as its own document type is deliberate: a correction says "the book was wrong," a scrap says "the goods are gone and here is why." Mixing them in one bucket makes the periodic adjustment review — one of the most useful management reads in stock control — much less informative, because real losses and bookkeeping fixes blur together.
When to adjust — and when not to
The most damaging adjustment habit is using it as a universal eraser. The rule from the counting guide applies with full force: investigate first, adjust second — because an adjustment is only correct when the variance has no process explanation:
- Missing receipt? Post the receipt. Adjusting instead leaves purchase reconciliation and supplier history wrong even though the quantity looks right.
- Unrecorded issue? Post the issue — consumption history feeds reorder calculations, and an adjustment hides the demand.
- Stock in another location? Post a transfer — net zero, truth restored. An adjustment pair (down here, up there) doubles the noise in the adjustment report for no gain.
- Genuine physical difference, investigated? Now adjust — with a reason, at the right type, with approval where the value warrants it.
A useful management signal falls out of this discipline: once adjustments are only ever the last resort, their volume and value become a clean KPI for process health. Rising adjustments on one item, one store or one shift is an early-warning light, not background noise.
Could you explain every correction made last quarter?
We can show the adjustment flow with reasons, the ledger trail behind each posting, and the cancellation that reverses a mistake without deleting it.
Lot-level effects
Where lot and batch tracking is in force, an adjustment cannot stop at the aggregate balance — it must say which lot gained or lost quantity, or the batch detail drifts from the total it is supposed to explain. In Fast Inventory Software, lot-level adjustments update the lot contents alongside the aggregate stock, and when an adjustment takes a lot's quantity to zero or below, the lot is closed — its status flips so it drops out of available stock cleanly rather than lingering as an empty shell that still appears in FEFO candidate lists and expiry buckets.
The practical rule for teams: always adjust batch-controlled items at lot level, and let expired or damaged lots leave the book through the proper sequence — quarantine by status first, then write down by adjustment — so the expiry dashboard, the recall trail and the valuation all stay mutually consistent.
Cancellations — reverse the exact delta
Even corrections need correcting sometimes. The wrong way is deletion — the document vanishes, the balance snaps back, and the history now contains a hole that no auditor and no future investigator can explain. The right way, and the way the Fast platform works, is reversal: cancelling a document posts a reversing transaction that undoes the exact delta of the original, recorded under a cancellation type prefixed to the original's — so both the original posting and its reversal remain visible in the ledger, each with its own row.
"Exact delta" carries weight. The reversal restores precisely what the original changed — the same quantities against the same item, location and lot — rather than recomputing from current state, so a cancellation is safe even after other movements have happened in between. The ledger reads as what it is: an adjustment, discovered wrong, reversed — two rows, zero mystery.
Reason, approval and review discipline
Mechanism handles the how; discipline handles the who and why. Three habits separate a controlled adjustment practice from an eraser:
- A reason on every adjustment. "Count variance PHY/000123", "damaged in handling", "opening-balance correction" — one line that makes the ledger self-explanatory years later.
- Value-based approval. Set a money threshold above which a second person approves before posting. Quantity thresholds miss the point — losing 10,000 washers matters less than losing six drive motors. Role-based access decides who can post adjustments at all.
- A periodic adjustment review. Monthly, read the adjustment listing by value, item, store, user and reason. Patterns — the same item every month, one shift's numbers, growing scrap — are the cheapest process audit you will ever run, priced at the valuation rate the ledger already carries.
The best-practices checklist
- Corrections only ever as posted documents — never balance edits
- Investigate before adjusting; post the missing document where one exists
- Right type for the event — increase, decrease, or scrap kept distinct
- Batch items adjusted at lot level, empty lots closed
- A reason on every posting; value-based approval thresholds
- Mistakes reversed by exact-delta cancellation, never deleted
- Monthly adjustment review by value, item, user and reason
- Adjustment volume tracked as a process-health KPI, trending down
How Fast Inventory Software implements adjustments
In Fast Inventory Software, adjustments are documents on the shared movement engine: adjust-increase (ADI) and adjust-decrease (ADD), with scrap remove/add (SCR/SCA) as distinct types. Each posting updates the running stock balance — and the lot contents where batch control applies, closing a lot that reaches zero — and writes its row in the immutable stock ledger with quantity, type, reference and rate. Cancellations reverse the exact delta under a cancellation-prefixed type, so nothing is ever silently rewritten, and the platform's audit trail logs before/after images on every write underneath it all.
Around the mechanism sit the workflows this guide describes: physical stock taking records the variances that adjustments reconcile, role-based access controls who can post, and the reports layer gives you the stock ledger and valuation views that make the monthly adjustment review a ten-minute read.
Frequently asked questions
What is a stock adjustment?
A stock adjustment is a document that corrects on-hand stock outside the normal receipt and issue flow — an adjust-increase where physical stock exceeds the book, an adjust-decrease where the book exceeds physical. It exists for genuine corrections: count variances, damage, spillage, historical data errors. Because it is a document, not an edit, every adjustment updates the stock balance at commit and writes its own row in the immutable stock ledger, so the correction is dated, quantified, attributable and permanently traceable.
Why should stock never be corrected by directly editing the balance?
Because a direct edit changes the number and destroys the story. An edited balance cannot tell an auditor — or you, three months later — what the stock was before, why it changed, who changed it or what it was worth. Corrections posted as adjustment documents preserve all of that: the before-quantity, the delta, the reason, the user and the rate all survive in the ledger. The practical test of any inventory system is whether stock can change without a document; if it can, the audit trail is decorative.
When is a stock adjustment the wrong tool?
Whenever the variance has a process explanation. An unposted goods receipt should be posted as a receipt; an unrecorded issue as an issue; stock found in a different location as a transfer. Using adjustments to paper over missing documents makes the books balance while hiding the process fault — and it corrupts movement history, purchase reconciliation and costing. Adjust only for genuine physical differences that have been investigated: damage, loss, count variance with no other explanation.
How are stock adjustments cancelled or reversed?
By reversal, not deletion. In Fast Inventory Software a cancellation posts a reversing transaction that undoes the exact delta of the original document, prefixed as a cancellation type, leaving both the original and the reversal visible in the ledger. Nothing is edited in place and nothing disappears. That way the history always explains itself: a mistaken adjustment and its reversal are two ledger rows, not a silent rewrite.
What approval discipline should adjustments have?
Small, investigated variances can be posted by the stores lead; larger values should need a second pair of eyes before posting, with the threshold set in money terms, not quantity. Every adjustment should carry a reason, and the adjustment listing should be reviewed periodically — by value, by item, by user and by reason. A rising adjustment trend on an item is an early warning of a process fault, and role-based access should decide who can post adjustments at all.