An obsolete inventory write-off runs on two separate tracks, and they don’t move at the same speed. Under GAAP, you record the loss as soon as you identify the impaired stock and write it down to net realizable value. For tax purposes, the IRS generally won’t let you deduct the loss until you actually dispose of the goods, sell them below cost, or offer them at a reduced price within a defined window. Treating the two as one process is where businesses lose deductions and end up with balance sheets that don’t match reality.
What Counts as Obsolete Inventory
Obsolete inventory is stock you’re unlikely to sell or use in production at normal prices. The goods may be physically intact, but they’ve lost economic value because of technological change, expired demand, deterioration, or overstocking that outran realistic sales forecasts.
Identification usually combines three inputs. An inventory aging report flags items that have sat beyond a set threshold. A sales forecast comparison shows where quantities on hand outrun any reasonable demand. Physical inspection by warehouse staff confirms whether the flagged goods are damaged, expired, or unmarketable. Data alone catches slow movers; only hands-on review confirms condition. That combined record is what supports both the book write-down and, later, the tax deduction.
Writing the Inventory Down Under GAAP
For inventory measured using FIFO, average cost, or any method other than LIFO or the retail method, U.S. GAAP requires carrying stock at the lower of cost and net realizable value. Net realizable value is the estimated selling price in the ordinary course of business, minus reasonably predictable costs of completion, disposal, and transportation.1Financial Accounting Standards Board. ASU 2015-11 Inventory (Topic 330) For truly obsolete goods, NRV is often zero or close to it, and the entire carrying cost becomes a loss.
You recognize that loss in the period you identify it. Waiting until the goods leave the building is not a GAAP option.
The Journal Entry
Most companies debit Cost of Goods Sold, or a separate loss account such as “Loss on Inventory Obsolescence,” and credit an Allowance for Inventory Obsolescence. Using an allowance rather than reducing Inventory directly preserves the original cost in the general ledger while showing the net value on the balance sheet. Inventory that originally cost $100,000 with a $40,000 allowance appears as $60,000 net. Auditors can still trace the full cost, and the balance sheet reflects realistic value.
The income statement hit lands immediately. Gross profit or operating income drops in the current period, and for businesses with heavy obsolescence exposure, a single quarter’s write-down can move gross margin and current ratio noticeably.
Apply write-downs to specific items or identifiable categories rather than as a blanket percentage across all stock. Specific identification is what LCNRV requires and what auditors expect to see documented. If market conditions later improve, U.S. GAAP does not allow you to reverse the write-down above the item’s original cost.
Clearing the Books When the Goods Leave
The write-down created a reserve; it did not remove the inventory from the ledger. When you scrap the goods with no recovery, you debit the Allowance for Inventory Obsolescence and credit Inventory for the full original cost. If you sell for a nominal amount, you debit Cash for the recovery, debit the Allowance for the written-down portion, and credit Inventory for the original cost. The loss itself was already recognized when you set up the reserve.
Why the Tax Deduction Lags the Book Loss
This is where many businesses trip. The financial write-down you just recorded does not automatically produce a tax deduction. The IRS generally does not allow a deduction based solely on creating a book reserve or allowance for obsolete inventory. It requires something more concrete: an actual offering at reduced price, a sale, or physical destruction.
The 30-Day Offering Rule
Treasury Regulation 1.471-2(c) lets you value unsalable or unusable goods at their bona fide selling price minus direct disposal costs, but only if the selling price reflects an actual offering of those goods during a period ending no later than 30 days after the inventory date.2eCFR. 26 CFR 1.471-2 – Valuation of Inventories The regulation covers goods that are damaged, imperfect, shop-worn, out of style, or in odd or broken lots. Marking them down on paper doesn’t qualify. You have to try to sell them.
The burden of proof falls on you. Keep records showing the goods actually fit those classifications and documenting how they were offered and eventually disposed of.2eCFR. 26 CFR 1.471-2 – Valuation of Inventories
Deducting the Full Cost
To deduct the full cost of worthless inventory, you generally need to show the goods were physically destroyed, scrapped, or sold below cost. Physical destruction produces the cleanest evidence. If the goods stay on hand, offering them at reduced prices to the public or through liquidation channels can support the deduction, provided you document the offer and the actual sales.
Documentation the IRS expects includes physical count sheets, records of the destruction process (date, method, items destroyed), and third-party verification such as a certified destruction certificate. For goods sold at a discount, keep the sales invoices and evidence of the promotional effort.
The Book-Tax Timing Gap
Because GAAP requires loss recognition on identification while the IRS defers the deduction until disposition, a temporary difference opens up. The inventory’s carrying value on your balance sheet, after the write-down, is lower than its tax basis, which still sits at full cost. Under ASC 740, this deductible temporary difference creates a deferred tax asset representing the future tax benefit you’ll receive when you eventually dispose of the stock and claim the deduction. If realization of that benefit is uncertain, you may need to record a valuation allowance against it.
Choosing a Disposition Method
How you get rid of the physical stock affects the cash you recover, the documentation you generate, and, in some cases, the size of the deduction itself.
Liquidation Sales
Selling obsolete stock at a deep discount through liquidation channels or secondary markets recovers some cash and produces clean invoices for the tax record. Under Treas. Reg. 1.471-2(c), the reduced selling price must be genuine and the offering legitimate. A token sale to a related party won’t hold up.2eCFR. 26 CFR 1.471-2 – Valuation of Inventories
Scrapping and Destruction
When goods have no resale value or carry liability risk, destruction is the right path. Record the date, the method, and the specific items destroyed. A third-party witness or compliance officer verifying the destruction strengthens the record and supports the deduction for the full cost basis.
Charitable Donation
Donating obsolete inventory to a qualified charity can produce a tax benefit larger than a simple cost-basis deduction. Under IRC Section 170(e)(3), a C corporation donating inventory to a qualifying organization can claim an enhanced deduction equal to the item’s cost basis plus half the difference between cost basis and fair market value, with the total capped at twice the basis.3Office of the Law Revision Counsel. 26 USC 170 – Charitable, Etc., Contributions and Gifts
Conditions are strict. The charity must use the donated property for the care of the ill, the needy, or infants. It cannot resell the goods, and it must provide a written statement confirming it will use and dispose of the property accordingly. If the donated items are regulated under the Federal Food, Drug, and Cosmetic Act, they must fully comply with that law on the donation date and for the 180 days prior.3Office of the Law Revision Counsel. 26 USC 170 – Charitable, Etc., Contributions and Gifts
Food donations are treated more broadly. Any business, not just C corporations, can claim the enhanced deduction for apparently wholesome food donated from a trade or business, subject to a 15% cap on aggregate net income from the contributing trades or businesses for non-C-corporation taxpayers.3Office of the Law Revision Counsel. 26 USC 170 – Charitable, Etc., Contributions and Gifts
Documentation That Supports Both Tracks
The same records that satisfy your auditor generally satisfy the IRS. Keep aging reports and physical inspection notes that identify the goods as obsolete, the write-down calculation applied to specific items or categories, and the disposition evidence — destruction certificates, liquidation sales invoices, or charitable donation acknowledgment letters with the required use statements.
Retain everything for as long as the relevant tax year is open for audit. That is generally three years from the filing date and extends to six years if gross income is underreported by more than 25%. If the disposal method involves hazardous waste, federal recordkeeping rules require keeping manifests, test results, and waste analysis records for at least three years from the date the waste was last sent for treatment, storage, or disposal.4eCFR. 40 CFR Part 262 – Standards Applicable to Generators of Hazardous Waste Aligning environmental and tax retention to the longer period closes gaps that could cost you a deduction.
Small Business Exemption and Method Changes
Businesses meeting the gross receipts test under Section 448(c), generally those averaging $30 million or less in annual gross receipts over the prior three years, can elect to treat inventory as non-incidental materials and supplies or conform to their financial statement method.5Office of the Law Revision Counsel. 26 USC 471 – General Rule for Inventories That simplified approach can shrink the book-tax timing gap. Any method change triggers a Section 481(a) adjustment.
Changing how you value inventory, whether adopting the small business exemption, switching to lower of cost or market, or correcting a method you’d been applying incorrectly, requires filing Form 3115, Application for Change in Accounting Method. Many inventory changes qualify for automatic consent, which lets you attach Form 3115 to your timely filed return for the year of change and send a signed copy to the IRS National Office.6Internal Revenue Service. Instructions for Form 3115 Non-automatic changes must be filed during the tax year the change is to apply. Miss that window and you wait a year.
One Boundary Worth Flagging
Physical disposal isn’t always a simple dumpster decision. If any of your obsolete stock qualifies as hazardous waste under the Resource Conservation and Recovery Act, generator accumulation limits, manifests, and permitting rules apply before you can destroy or ship it out.4eCFR. 40 CFR Part 262 – Standards Applicable to Generators of Hazardous Waste Electronic goods containing lead, mercury, or certain batteries can also trigger those requirements depending on how they test. Building the environmental step into your disposition plan keeps the tax documentation clean, because the same manifests and destruction records that satisfy the EPA also satisfy the IRS.