Inventory accounting under GAAP, governed by Accounting Standards Codification Topic 330, requires U.S. companies to record inventory at the cost of bringing goods to a saleable condition and location, move that cost to cost of goods sold under a consistent cost flow method, and write the asset down when its value drops below that recorded cost. Inventory sits on the balance sheet as a current asset until sale, so the choices made along the way feed directly into reported profit.
What Counts as Inventory and Who Owns It
Inventory covers finished goods ready for customers, work in process, and raw materials waiting to enter production. At any balance sheet date, the question is not where the goods physically sit but who holds legal title. Get that wrong and two companies can claim the same asset, or a company can leave legitimate inventory off its books entirely.
Shipping Terms
Under Free on Board (FOB) Shipping Point terms, title passes to the buyer when the seller hands goods to the carrier. The buyer records the inventory while it is still in transit and bears the risk of loss. Under FOB Destination, the seller keeps title until the goods arrive at the buyer’s location and continues to report them as its own inventory throughout the journey.1Legal Information Institute. Free on Board (FOB) This matters most at year-end cutoff. A truckload of product moving on December 31 belongs on one balance sheet or the other, and misreading the terms creates material errors on both sides.
Consignment
Goods held on consignment stay on the consignor’s books. The consignee has physical possession and acts as a sales agent, but never records the goods as its own inventory, no matter how long they sit on the shelf. Only when a third-party buyer purchases the goods does the consignor remove them.
Sales With a Right of Return
When customers can return products, the seller recognizes revenue only for the portion of sales it expects to keep and books a refund liability for the units it expects back. Alongside that liability, the seller records a separate asset for its right to recover the returned products, measured at the inventory’s original carrying amount less any expected recovery costs or decline in value.2Financial Accounting Standards Board. Accounting Standards Update 2014-09 – Revenue From Contracts With Customers (Topic 606) Both the refund liability and the recovery asset get updated at each reporting date as return expectations shift.
What Goes Into the Cost of Inventory
ASC 330 requires inventory to be recorded at the total cost of bringing it to its present condition and location. Start with the supplier’s invoice price, reduced by volume discounts or early-payment incentives. Add inbound freight, insurance on goods in transit, and import duties or non-refundable taxes.
Manufacturers layer in more. Direct labor for production workers and an allocated share of manufacturing overhead (factory rent, equipment depreciation, utilities for the production facility) attach to each unit produced and stay on the balance sheet until the unit sells.
Interest is usually excluded. But when a company produces goods as discrete, long-duration projects (shipbuilders, real estate developers, custom yacht builders), interest incurred during the production period can be capitalized into the inventory’s cost when the effect is material.3Financial Accounting Standards Board. Summary of Statement No. 34 – Capitalization of Interest Cost A firm mass-producing consumer electronics would not capitalize interest; a firm building custom yachts likely would.
Some costs stay off the balance sheet no matter what. Outbound shipping to customers is a selling expense. Administrative salaries, marketing spend, and corporate overhead are period costs. If a cost did not help bring the product to a saleable state in the warehouse, it does not belong in the inventory account.
Choosing a Cost Flow Method
When a company buys identical goods at different prices, GAAP lets it choose how those costs attach to units sold. The bookkeeping choice does not have to mirror the physical movement of goods.
Under First-In, First-Out (FIFO), the oldest costs flow to cost of goods sold first, and the most recent purchase prices remain in ending inventory. The balance sheet stays close to current replacement cost, and during periods of rising prices, reported income runs higher because older, cheaper costs hit the income statement.
Last-In, First-Out (LIFO) works in reverse. The newest costs flow to cost of goods sold; the oldest costs stay on the balance sheet. In an inflationary environment, LIFO matches higher recent costs against current revenue and reduces taxable income. The trade-off is a balance sheet carrying inventory at prices from years or decades ago. LIFO is permitted under U.S. GAAP but prohibited under International Financial Reporting Standards, which matters for any company with international reporting obligations.
The Weighted-Average Cost method blends all purchase prices into a single average cost per unit and applies that average to both cost of goods sold and ending inventory. It smooths price fluctuations and is simpler to administer than tracking cost layers.
Specific Identification tracks the exact cost of each individual unit through the accounting cycle. It is the most precise method, but only practical for distinguishable, high-value items like custom machinery or fine art.
The Retail Inventory Method is common among retailers with high transaction volume. Instead of tracking cost item by item, a retailer computes a cost-to-retail percentage for groups of similar products and applies that ratio to the retail value of ending inventory to estimate cost. ASC 330 treats it as an acceptable approach, though it provides limited specific guidance on application.
The Special Rules Around LIFO
LIFO comes with strings that no other method has, so it deserves its own treatment.
The LIFO Conformity Rule
Under Section 472(c) of the Internal Revenue Code, a company that elects LIFO for tax purposes must also use LIFO when reporting income to shareholders, creditors, and other outside parties. That is the LIFO conformity rule. You cannot use LIFO on the tax return and FIFO in the annual report. Once elected, LIFO must be used in all subsequent tax years unless the IRS authorizes a change.4Office of the Law Revision Counsel. 26 USC 472 – Last-in, First-out Inventories
To adopt LIFO, a business files Form 970 with its income tax return for the first year the method will be used, including an analysis of all inventory at the beginning and end of that year and at the beginning of the prior year.5eCFR. 26 CFR 1.472-3 – Time and Manner of Making Election
The LIFO Reserve
Because LIFO can produce a balance sheet value far below current replacement cost, the SEC requires publicly traded companies using LIFO to disclose the difference. This LIFO reserve is the gap between the stated LIFO inventory value and what the inventory would be worth under a current-cost method. If material, it appears parenthetically on the balance sheet or in the footnotes.6eCFR. 17 CFR 210.5-02 – Balance Sheets Analysts use this disclosure to compare LIFO companies against FIFO companies on comparable footing.
LIFO Liquidation
A LIFO liquidation happens when a company sells more inventory than it replaces in a period, dipping into older cost layers carried at historically low prices. Those old, cheap costs flow into cost of goods sold and reported profit spikes artificially. The result can be a surprise tax bill driven by phantom profits that reflect no real improvement in the business. Companies expecting a liquidation sometimes disclose the estimated effect in their footnotes.
Writing Inventory Down When Value Falls
Inventory does not always hold its value. Damage, obsolescence, shifting demand, or falling market prices can push realistic selling prices below original cost. GAAP requires companies to catch these declines, and the specific test depends on the cost flow method.
Lower of Cost or Net Realizable Value
Companies using FIFO or weighted-average cost measure inventory at the lower of its recorded cost or its net realizable value (NRV). NRV is the estimated selling price in the ordinary course of business minus reasonably predictable costs to complete, sell, and transport.7Financial Accounting Standards Board. Accounting Standards Update 2015-11 – Inventory (Topic 330) – Simplifying the Measurement of Inventory When NRV falls below cost, the company records the difference as a loss in the current period. ASU 2015-11 introduced this simplified test and eliminated the older market-based ceiling-and-floor calculation for non-LIFO methods.
Lower of Cost or Market
Companies using LIFO or the retail inventory method still apply the older Lower of Cost or Market test. Here, “market” generally means current replacement cost, capped at a ceiling and a floor. The ceiling is net realizable value; the floor is net realizable value minus a normal profit margin.7Financial Accounting Standards Board. Accounting Standards Update 2015-11 – Inventory (Topic 330) – Simplifying the Measurement of Inventory If replacement cost falls between those bounds, it is the market value. Above the ceiling, use the ceiling; below the floor, use the floor. Compare that constrained market value to historical cost and take the lower figure.
Write-Downs Are Permanent
Once a company writes down inventory under GAAP, the reduced amount becomes the new cost basis. Even if market conditions improve later, the write-down cannot be reversed. This differs from IFRS, which does permit reversals. The one exception is inside interim reporting: a market-decline loss recognized in one quarter can be recovered in a later quarter of the same fiscal year, but only up to the amount originally written off.7Financial Accounting Standards Board. Accounting Standards Update 2015-11 – Inventory (Topic 330) – Simplifying the Measurement of Inventory
Tracking Systems and Physical Counts
GAAP does not mandate a specific tracking system. The choice between perpetual and periodic affects how a company monitors stock and calculates cost of goods sold.
A perpetual system updates the inventory account in real time with every purchase and every sale. When a unit sells, the system records both the revenue and the corresponding cost of goods sold immediately. Most large retailers and manufacturers use perpetual systems because they integrate with point-of-sale and warehouse management software.
A periodic system only calculates cost of goods sold at the end of a period, using a formula: beginning inventory plus net purchases minus ending inventory (from a physical count). Individual sales do not trigger a cost entry during the period. Recordkeeping is lighter, but the company is blind to shrinkage and stock levels between counts. Smaller businesses sometimes prefer periodic systems for the lower administrative burden.
No system eliminates the need to physically verify what is in the warehouse. Theft, damage, spoilage, and receiving errors create shrinkage between recorded quantities and reality. A full physical count shuts down operations while every location is counted, often annually at year-end. Cycle counting spreads the work across the year by counting rotating subsets, catching discrepancies sooner and avoiding shutdowns. Companies using the retail inventory method need actual shrinkage data from physical counts to calibrate their estimates at each reporting period.
When a count shows less than the books say, the company reduces the inventory account and recognizes a shrinkage expense or an increase to cost of goods sold. Small, consistent shrinkage often gets folded into cost of goods sold. Abnormally large or unusual losses are typically broken out separately so they do not distort normal operating metrics.
How Inventory Shows Up on the Financial Statements
Inventory sits on the balance sheet as a current asset because it is expected to convert to cash within one operating cycle. When goods sell, their assigned cost moves to the income statement as cost of goods sold and is matched against the revenue from the sale. The difference is gross profit.
SEC registrants must disclose several pieces of inventory information. The balance sheet or an accompanying note must break out major classes (finished goods, work in process, raw materials, supplies) separately where practicable. Companies must disclose the basis for determining inventory amounts and, if cost is used, describe which cost elements are included. The method used to remove costs from inventory (FIFO, LIFO, average cost) must be identified.6eCFR. 17 CFR 210.5-02 – Balance Sheets A significant write-down requires disclosure of the reason and the amount. Inventory pledged as collateral for loans or credit facilities must also be disclosed.
Changing Inventory Methods
A company that wants to switch cost flow methods must justify that the new method is preferable. GAAP treats the switch as a change in accounting principle, applied retrospectively: prior-period statements are restated as if the new method had always been used, with the cumulative effect reflected in the opening balance of retained earnings for the earliest period presented.
If retrospective application is impracticable because historical data cannot be reconstructed, the new method is applied prospectively from the earliest date possible. Either way, the company discloses the nature of the change, the reason the new method is preferable, and the effect on each financial statement line item. Switching away from LIFO for tax purposes requires IRS approval, which adds another layer of process for any company reconsidering its inventory strategy.