Inventory reconciliation: resolve count and ERP differences

Your count sheet shows 900 units of a SKU, while the ERP shows 936. Inventory reconciliation starts by making those quantities comparable: the same item, location, stock status, unit, and cutoff. Trace receipts, issues, and transfers back to that cutoff before treating the difference as missing stock. Investigate the remaining exception, have an authorized owner make any required source correction, and refresh the evidence.

Keep the physical observation separate from the recorded balance throughout the review. A count proves what was observed within its stated scope; an ERP export proves what was recorded at its extraction time. Neither establishes why they differ. A controller needs the movement records and investigation outcome before deciding how a correction should be recorded.

Agree on the stock scope before comparing quantities

Have the inventory owner identify the company, SKU, warehouse, and bins covered by the count. Include lot or serial identity where it changes which stock is being counted. A transfer to another warehouse can reduce the counted location without reducing company-wide inventory, so a company total cannot validate a warehouse count.

Declare the stock-status rule. Released, quarantined, damaged, reserved, and consigned quantities may require separate comparisons under your operating policies. Reservation affects availability without necessarily changing physical possession. If the count includes held stock but the report includes only released stock, retain separate status balances rather than reporting their difference as a shortage.

Resolve item identity before adding quantities. A supplier code on a packing slip, an ERP item ID, and a count label can represent the same SKU, but similar descriptions do not establish that match. Preserve each source identifier with the approved mapping, including its effective date when a pack or item revision changes. Leave an unmapped record visible until the item owner resolves it.

Align the count cutoff and the unit conversion

Choose a cutoff with a time zone, then record when the count occurred and when each source was extracted. If movements continue during counting, capture the transactions affecting each counted location and item while the count is in progress. A count made before a receipt cannot be compared with a balance that already includes that receipt without an adjustment to the comparison basis.

Keep movement time and posting time in separate fields. A receipt that happened before the cutoff but was posted later needs the receiving evidence to establish which period it belongs to. A receipt that happened after the cutoff belongs outside this comparison even if it appears in the latest ERP export. The controller and warehouse owner agree on that basis; the report preserves both timestamps instead of guessing from one date.

Convert every input into the agreed base unit. A count of 75 cases at 12 each per case is 900 each, not 75 each. Use the item-specific conversion that applied when the movement occurred (a changed case pack can invalidate a current conversion applied to older records). Preserve the original quantity and unit alongside the converted value so a reviewer can repeat the calculation.

Assign signs from the movement type and location. Receipts into the counted scope are positive; issues and transfers out are negative. A transfer has a separate destination leg, which belongs in the destination scope. A duplicate export of the same transaction must not become another movement, so retain a stable source transaction and line reference before combining files.

Reconstruct the expected balance at the count time

This synthetic example covers SKU W100, released stock in warehouse MAIN, through September 30 at 23:59:59 America/Chicago. The opening balance is 900 each. A case contains 12 each throughout the example. The count excludes warehouse OVERFLOW, and all movements below refer to the same item and released-stock scope.

The expected cutoff balance is 900 + 120 - 84 - 24 = 912 each. The physical count is 75 × 12 = 900 each, leaving a variance of 900 - 912 = -12 each. Record that as an unresolved shortage for investigation. The arithmetic establishes the remaining difference, not its cause or the accounting treatment.

A next-day ERP export includes receipt R101 and shows 936 each: 912 + 24. Comparing the count of 900 with that export gives -36 each. Of that apparent shortage, -24 comes from comparing different cutoffs; -12 remains after the post-cutoff receipt is excluded. Do not post a 36-unit adjustment to make the two exports agree.

The physical count is an observation, so adding its 900 units to the transaction balance would count existing stock again. Opening balances also need a defined boundary: include only later movements when reconstructing the closing quantity. Retain the opening snapshot reference so the reviewer can check that the receipt or issue was not already inside it.

Download the synthetic inventory reconciliation CSV to inspect the raw units, signed movements, cutoff treatment, and count comparison. The file is a worked example, not an ERP import template. Substitute your own scope and evidence before using its calculation in a stock review.

Investigate the remaining variance with a named owner

Give the 12-unit exception to an inventory owner who can inspect the counted bins, issue records, and receiving evidence. A recount checks the observation; a transaction review checks whether an issue, receipt, or transfer is missing or duplicated. Keep those checks separate so an unexplained balancing entry cannot pass as proof of the cause.

Record the case with its SKU, location, signed variance, evidence references, reviewer, and current status. Attach the proposed correction to the specific error being corrected. If the evidence is incomplete, retain an unresolved status and describe the missing source. A small net difference can conceal a missing receipt and a missing issue that offset each other.

The controller defines approval thresholds and the required review for quantities or items with special controls. Those thresholds determine the workflow, not whether the source evidence remains available. If an adjustment is approved, the authorized ERP owner records it using the native transaction process and returns the adjustment reference to the investigation record.

Refresh the comparison after the source correction and retain both the prior and revised snapshots. Verify that the correction reached the expected item and location, and explain which approved action changed the variance. Preserve the historical count even when the corrected ERP balance now agrees; that observation remains part of the review evidence.

Carry resolved stock quantities into operating reports

Before the next cycle, review whether the exception came from a count error, delayed posting, missing transaction, duplicate source row, or changed item mapping. Preserve the evidence supporting that classification. Repeat problems need an owner for the source process or reporting rule, rather than a recurring unexplained adjustment.

A manufacturing dashboard can show the remaining variance with its location, age, and source refresh time. Keep unresolved quantities visible when aggregating stock across plants. A total that mixes approved corrections with open exceptions needs that distinction before it is used to promise production or delivery.

Use reconciled stock as an input to SIOP in manufacturing, where demand, supply, and capacity determine the production commitment. Quantity agreement alone does not establish availability: a reconciled unit can still be held, reserved, or unsuitable for the intended order. Preserve the eligibility rules when carrying inventory into the planning view.

How Permute builds a repeatable inventory comparison

Permute sells connected data and custom reporting software for businesses with fragmented operating and financial records. We combine ERP inputs from sources such as NetSuite or SAP with supplied count files, preserve source references, and apply approved item and location mappings. Conflicting identities stay available for review instead of being added into a stock total by description.

We turn agreed conversion, scope, and cutoff rules into reusable reporting logic. A controller can inspect which movements support the expected balance, while an inventory lead can trace the remaining variance to the count and transaction evidence. Source timestamps stay with the output so a stale export cannot appear to be a current stock observation.

We scope access to the underlying records and reporting outputs. Review how the data is handled before sharing supplier terms, costing fields, or warehouse evidence outside the team that needs them. An inventory comparison can expose quantity evidence without giving every participant access to unrelated financial records.

Keep physical checks and ERP corrections with their owners

This workflow reads inventory evidence and produces a comparison; it does not post stock adjustments back to an ERP. We do not perform physical counts, authorize inventory movements, or choose an accounting treatment. General ledger reconciliation and financial-close decisions remain with finance and its accounting tools.

Use scheduled reporting with displayed refresh times for management review. We do not promise a live warehouse balance, and we are not a forecasting engine. If a feed is incomplete, or movements continued without usable timestamps during the count, keep the comparison provisional until the responsible owner supplies enough evidence.

Inventory reconciliation compares a physical observation with the recorded quantity for the same stock scope and cutoff. Item mappings, dated unit conversions, and signed movements explain which differences come from the comparison basis. The remaining variance needs investigation and an authorized source correction where the evidence supports one. Retaining the count, source references, and refreshed comparison makes that decision reviewable in the next cycle.

Questions about inventory count differences