Every warehouse ends up with numbers that don't quite match reality. A pallet goes missing, a barcode gets scanned twice, or damaged stock sits unrecorded in a corner. A solid stock adjustment process turns these discrepancies into clean, auditable records rather than a headache for your finance team.
What is a stock adjustment?
A stock adjustment is a formal change to the quantity or value of inventory recorded in your system, made to reflect what's actually on the shelf. It corrects the gap between book stock and physical stock. Common causes include damage, theft, expiry, picking errors, supplier shortages and cycle count variances.
In practice, this isn't just a warehouse task. Adjustments affect your balance sheet, your cost of goods sold, and potentially your tax position. Therefore, HMRC and UK GAAP both expect adjustments to be recorded with a clear reason, a date, and evidence to back them up.
Why the stock adjustment process matters
Without a structured process, adjustments become guesswork. Staff might change quantities on the fly, with no record of why. As a result, stock accuracy drifts, audits take longer, and finance teams struggle to trust the numbers.
A well-designed inventory adjustment procedure protects your business in three ways. First, it gives you an audit trail if HMRC or your accountants ask questions. Second, it helps you spot recurring problems, such as a supplier consistently short-shipping. Finally, it keeps your reported stock value accurate for Companies House filings and management accounts.
Building your stock adjustment process step by step
A repeatable process removes ambiguity and speeds up approvals. Here's a practical structure that works for SMEs and larger operations alike.
1. Identify the discrepancy. This usually comes from a cycle count, a full stocktake, or a picking error flagged during fulfilment.
2. Investigate the root cause. Before adjusting anything, check for simple explanations, such as a miscount or an unrecorded goods receipt. Our guide to root cause analysis for recurring stock discrepancies covers this in more depth.
3. Document the evidence. Record photos of damaged goods, delivery notes, or count sheets. This step matters most for write-offs, since HMRC expects supporting evidence for anything deducted from taxable profit.
4. Submit for approval. Route the adjustment to a named approver before it hits the system.
5. Record and post the adjustment. Once approved, log it in your WMS or inventory system with a reason code, quantity, value and reference number.
6. Review periodically. Track adjustment trends monthly to catch patterns early.
How to approve stock adjustments
Approval limits should scale with financial impact. A sensible structure looks like this:
- Under £100 or minor quantity variances: team leader sign-off.
- £100 to £1,000: warehouse manager approval, with evidence attached.
- Over £1,000, or any suspected theft: finance director or senior manager approval, plus a written incident report.
This tiered approach keeps small day-to-day corrections moving quickly, while larger warehouse stock adjustments get proper scrutiny. Consequently, you reduce fraud risk without slowing down routine operations.
Stock write-off approval and tax implications
A write-off removes stock from your books entirely, usually due to damage, obsolescence or theft. Unlike a routine adjustment, a write-off directly reduces your reported profit, so HMRC guidance on trading losses is relevant here.
Best practice is to require two levels of sign-off for any write-off above a set threshold, alongside photographic evidence and a brief explanation. For a deeper look at valuation methods and accounting treatment, see our guide on inventory write-offs.
How often should stock adjustments be reviewed?
Most UK warehouses benefit from a monthly review of adjustment logs, alongside quarterly deep dives into trends by SKU, location and reason code. High-value or fast-moving stock may need weekly checks. In contrast, slow-moving or low-value items can be reviewed less frequently.
Regular review also feeds into your stock count tolerances, helping you set realistic thresholds rather than chasing every tiny variance.
Common pitfalls to avoid
Many businesses fall into the same traps. For example, allowing anyone to adjust stock without approval, skipping evidence collection, or failing to link adjustments back to root causes. Similarly, relying on spreadsheets rather than a proper WMS makes audit trails difficult to maintain, a problem we explore in moving from spreadsheets to real-time inventory control.
Frequently asked questions
What is a stock adjustment in simple terms?
It's a correction made to your recorded inventory to match what's physically in the warehouse, backed by a reason and supporting evidence.
Who should approve stock adjustments?
Approval should scale with value, from team leaders for small variances to senior managers or finance directors for significant write-offs.
Do stock adjustments affect tax reporting?
Yes. Write-offs reduce taxable profit, so HMRC expects clear documentation and a consistent inventory adjustment procedure.
Conclusion
A clear stock adjustment process protects your stock accuracy, your finances, and your standing with HMRC. Start with simple approval tiers and regular reviews, then tighten the process as your volumes grow.
