Cost of goods sold for imported inventory: how to calculate it when you buy in dollars

A company that imports goods and sells them in local currency often finds at month end that gross margin moved even though no price changed. The cause is almost always in cost of goods sold: what was capitalized, at which exchange rate, and where an FX difference ended up.

At Soulbit Academy we explain cost of goods sold from the point of view of a CFO who buys inventory in dollars and operates in Latin America, with a focus on Mexico and Colombia. This article is part of the CFO Kit financial statements series: it starts from reading the income statement in two currencies and adds the cost calculation that feeds it.

Cost of goods sold formula and what it measures

Cost of goods sold is the acquisition or production cost of the units a company sold in the period. It equals opening inventory plus net purchases minus closing inventory. It is the first deduction in the income statement, and sales minus COGS is gross profit.

The formula needs two consistent pieces of data: what the available units cost and what the unsold units are worth. Opening inventory is last period's closing balance. Net purchases are the period's purchases less returns and trade discounts. Closing inventory is the balance at period end, from a physical count or from perpetual records.

There are two systems that reach the same result. In the periodic system, the company counts inventory at period end and derives COGS by difference. In the perpetual system, each sale releases its cost immediately and the balance is always known. The second takes more discipline and catches shrinkage before the close.

An error in closing inventory flows straight into COGS. If closing inventory is overstated by 10,000, gross profit is inflated by 10,000. That is why imported inventory needs a clear rule on which costs are capitalized and in which currency they are measured.

Landed cost: what goes into imported inventory

The cost of imported inventory includes everything needed to bring the goods to the warehouse in saleable condition. IAS 2 defines it in paragraph 11 as the purchase price, import duties, taxes that are not recoverable, transport, handling and other directly attributable costs, less trade discounts. Mexican entities reporting under NIF should check the current edition of CINIF's NIF C-4 before applying this IFRS-based treatment.

For an importer this becomes five components. The first is the supplier's invoice price. The second is international freight and insurance. The third is the customs duty paid at the border. The fourth is the customs broker's fee and other directly attributable clearance costs. The fifth is inland transport to the warehouse. All five are added to inventory cost and not expensed in the period.

Three items stay out. The first is import VAT the company can credit or deduct, because it comes back from the tax authority. The second is storage after arrival, unless it is needed to make the product saleable. The third is selling and administrative expense, which goes to profit or loss. The Mexican customs entry or the Colombian import declaration lists every concept, and you should reconcile them one by one. The article on the pedimento and supplier payment covers that document.

Table 1 summarizes the treatment of each component.

Component	In inventory cost?	Treatment
Supplier invoice price	Yes	Capitalized, net of trade discounts
International freight and insurance	Yes	Capitalized at the exchange rate on the transaction date
Customs duty	Yes	Capitalized when the company cannot recover it
Customs broker and clearance fees	Yes	Capitalized if directly attributable to the purchase
Creditable or deductible import VAT	No	Recorded as a tax receivable
Exchange difference on supplier payment	No	Profit or loss, as exchange difference
Selling and administrative expense	No	Expensed in the period

The underlying test is recoverability. If the tax comes back through a credit or refund, it is not a cost. Each country defines which VAT is recoverable, so confirm the treatment with your accountant.

Exchange rate: which date applies to each component

Each dollar component is converted to the functional currency at the rate on the date the company recognizes the transaction. Inventory is a non-monetary item measured at cost, so once recorded it is not retranslated at later rates. The full rule is in the article on IAS 21 and NIF B-15, and here we only apply it to inventory.

In practice, the transaction date for imported inventory is when the company gains control of the goods and the risk passes to it. That depends on the delivery terms agreed with the supplier and on the customs document. Pick one criterion, document it and apply it every time.

Duties paid in local currency at customs need no conversion. Components paid in dollars, such as freight, are converted at the rate on each payment date or, if accrued, on the date they are recognized. In Colombia the usual source is the daily TRM, and the article on the TRM and DIAN explains which one to use. In Mexico, the customs entry declares an exchange rate for customs purposes that does not always match the one used in accounting.

What if the goods were ordered in one month and received in another?

Record them at the rate on the recognition date defined in your policy, not at the purchase order date. If there is an advance to the supplier, the advanced portion usually keeps the rate of the advance date. Document the order, advance, delivery and payment dates of each shipment.

Why the payment exchange difference stays out of cost of goods sold

The exchange difference between the inventory recognition date and the supplier payment date goes to profit or loss and is not added to COGS. The payable to the supplier is a monetary item: it is retranslated at each close and when settled. Inventory stays fixed. IAS 21 states that exchange differences on monetary items are recognized in profit or loss.

Cost of goods sold answers how much the goods cost the day the company took ownership. The exchange difference answers how much the company gained or lost by leaving a dollar debt open. Mixing them hides currency exposure inside gross margin.

An assumed example shows the effect. A company records inventory at 4,000 pesos per dollar and pays thirty days later at 4,150. Inventory still costs the same, and the loss of 150 pesos per dollar owed goes to profit or loss. If the company added it to cost, the product would look more expensive and gross margin lower, although the problem was in treasury.

With COGS free of exchange differences, the CFO can analyze trading margin and financial result separately. Contribution margin by product and currency relies on that separation.

Cost of goods sold with FIFO or weighted average: an example with assumptions

Cost of goods sold depends on the valuation formula when unit cost changes between purchases. IAS 2 requires FIFO or weighted average for interchangeable inventory and specific identification for non-interchangeable items. LIFO is not a permitted IFRS formula. Use the same formula for inventories of similar nature and use. Mexican NIF reporting requires checking the current NIF C-4.

The following example is hypothetical, uses labeled assumptions and does not represent Soulbit prices or results. Assumptions: a Colombian distributor buys 500 units at 40 dollars, which is 20,000 dollars. Freight and insurance total 1,500 dollars. Customs duty is 8,000,000 pesos and the broker's fee is 2,500,000 pesos, both paid in pesos. The rate on the transaction date is 4,000 pesos per dollar. Import VAT is recoverable and excluded.

Landed cost: 20,000 times 4,000 is 80,000,000 pesos; 1,500 times 4,000 is 6,000,000; plus 8,000,000 and 2,500,000. The total is 96,500,000 pesos, or 193,000 per unit. Paying the supplier thirty days later at 4,150 costs 83,000,000 pesos. The 3,000,000 difference goes to profit or loss, not to inventory.

Further assumptions: opening inventory is 100 units at 190,000 pesos, or 19,000,000. The company sells 450 units, leaving 150. Table 2 compares both formulas.

Item (Colombian pesos, assumptions)	Weighted average	FIFO
Units available: 100 opening and 500 purchased	600	600
Cost of units available	115,500,000	115,500,000
Unit cost applied to issues	192,500 average	190,000 for the first 100; 193,000 for the other 350
Cost of goods sold, 450 units	86,625,000	86,550,000
Closing inventory, 150 units	28,875,000	28,950,000

Both formulas split the same available cost of 115,500,000 pesos; only the split changes. The 75,000 difference is small because unit cost moved little. With a more volatile exchange rate it grows.

Check: 19,000,000 plus 96,500,000 minus 28,875,000 gives 86,625,000, the weighted average COGS.

Common mistakes in cost of goods sold with dollar inventory

Five mistakes recur when calculating cost of goods sold for imported inventory. The first is adding the supplier payment exchange difference to cost. The second is forgetting freight, insurance or the broker because they sit on separate invoices. The third is capitalizing recoverable VAT. The fourth is retranslating inventory every month at the closing rate. The fifth is changing the valuation formula without applying it consistently.

The first safeguard is a reconciliation per shipment. Each import needs a file with the supplier invoice, the customs document, freight and clearance invoices, the exchange rate applied to each component and the payment proof.

How does a rising exchange rate show up in margin?

A higher rate makes new shipments more expensive. Under FIFO the effect reaches COGS with a lag, when older goods run out. Under weighted average it is diluted in the average cost. In both cases, pricing should be reviewed against replacement cost, not only against the book cost of inventory.

The second safeguard is to split the monthly report into COGS, realized exchange difference and unrealized exchange difference on payables.

What Soulbit V1 delivers and what it does not

Soulbit does not calculate cost of goods sold or value inventory. It is an institutional custody platform with MPC, OTC conversion by quote and payments, not an accounting system. V1 includes USDC and USDT balances, fiat in dollars, euros and pounds, recurring and batch payments, payment links, collection QR codes, KYB, AML/KYT monitoring and human support.

The V1 local bank rail exists only in Colombia. For a Mexican company, the platform has no local rail in Mexican pesos. Inventory accounting, the exchange rate for each component, the customs entry, the broker and the cost calculation remain the responsibility of the company and its accountant.

Where Soulbit can help is after the payment decision. A company can hold stablecoin balances, convert them by OTC quote and keep a record of dates and amounts that helps document the rate on each payment.