The Currency Behind the Closing File: Documenting Functional Currency Before the First Foreign Audit

A U.S. mid-market company acquires a foreign subsidiary and spends the weeks before closing on purchase price, regulatory approvals, and integration planning. Functional currency is frequently left to the accountants, who are expected to select the obvious answer once the opening balance sheet is assembled. That sequence is backwards. By the time the first foreign audit cycle begins, the currency determination may already be embedded in intercompany invoices, local statutory accounts, lender covenants, and dividend assumptions. Changing it later is not a bookkeeping adjustment; it is a restatement of the commercial logic behind the structure.

Why the Determination Is More Than an Accounting Election

Under U.S. GAAP, functional currency is the currency of the primary economic environment in which an entity operates. Under IAS 21, the concept is similar. Tax rules add another layer: U.S. international tax principles look to the functional currency of a qualified business unit, and local tax authorities may apply their own tests. The accounting and tax answers often align, but they are not guaranteed to. A subsidiary that sells in euros, pays employees in euros, and borrows in euros may still have material U.S. dollar funding, intercompany pricing, or head-office dependence that complicates the analysis.

The practical risk is not that the company chooses the wrong currency in a theoretical sense. It is that the company never records why it chose the currency it did. Without a contemporaneous memorandum, the first auditor, tax examiner, or lender asking the question receives a reconstructed rationale. That is a weaker position than a documented determination prepared before the first ledger is translated.

Where Currency Mismatches Begin to Distort

A functional currency determination travels through the subsidiary’s reporting in several directions at once. The most visible is translation. The less visible, and often more expensive, is the effect on commercial arrangements that were priced in one currency but recorded in another.

Intercompany Pricing

Transfer pricing policies are usually expressed in the functional currency of the tested party. If headquarters assumes the subsidiary transacts in U.S. dollars while the local books are kept in another currency, the intercompany invoice may include a currency conversion that no one has tested. A service fee or royalty calculated in dollars and settled in local currency can produce a margin that drifts with exchange rates, not with the functions performed. The tax file then shows a price that is defensible in one currency and less defensible in another.

Dividend Capacity

Dividend capacity is determined by local law, distributable reserves, and the subsidiary’s ability to transfer funds. Those reserves are stated in the local currency. A U.S. parent may model repatriation in dollars, but the legal ability to distribute depends on the local balance sheet. If the functional currency determination affects how retained earnings are translated, the parent’s repatriation plan can overstate the amount available in the year it is needed. The issue becomes acute when the subsidiary has accumulated translation adjustments or when the local currency is volatile against the dollar.

Covenant Calculations

Lenders often draft covenants in the reporting currency of the parent. A foreign subsidiary may borrow locally, generate local-currency EBITDA, and report into a dollar-denominated covenant. The functional currency determines how those results are translated and whether exchange movements flow through earnings or equity. A covenant that looks comfortably met in local currency can tighten materially in the parent’s reporting currency. Finance teams should test the covenant calculation in both currencies before signing the facility letter, not after the first compliance certificate.

Local Statutory Filings

Local statutory accounts, tax returns, and regulatory filings typically follow local currency and local GAAP. The functional currency used for group reporting may differ from the currency required for statutory purposes. That difference is manageable if it is mapped. It becomes a reconciliation problem if the group assumes the local books are already prepared on the same basis as the consolidated accounts. The first audit is a poor time to discover that the subsidiary’s statutory reserve calculation uses a different currency convention than the group’s dividend model.

The Pre-Close Documentation Checklist

A functional currency memorandum does not need to be long, but it should be prepared before closing and retained with the acquisition file. The following checklist is designed for U.S. mid-market acquirers and their advisers.

1. Identify the primary economic environment. Document the currency of sales, costs, financing, and cash flows. Include the basis for any judgment where indicators conflict.
2. Separate accounting and tax conclusions. State whether the functional currency for U.S. GAAP, local GAAP, and U.S. international tax purposes is the same. If not, explain why.
3. Map intercompany arrangements. List each material intercompany agreement, the currency in which it is priced, and the currency in which it is settled. Flag any mismatch.
4. Test dividend capacity in local currency. Confirm distributable reserves, withholding tax, and any local regulatory approval requirements before modeling repatriation in dollars.
5. Run covenant calculations in both currencies. Identify the reporting currency in the credit agreement and stress-test the headline ratios for exchange-rate movement.
6. Confirm statutory filing conventions. Obtain the local filing currency, local GAAP basis, and any translation requirements for group reporting.
7. Record the review date and owner. Assign responsibility for updating the memorandum if the subsidiary’s financing, sales mix, or intercompany arrangements change after closing.

A Determination That Can Be Defended

The first foreign audit cycle is not simply a test of balances. It is a test of whether the acquirer understood the entity it bought. A functional currency memorandum prepared before closing gives the finance team a reference point for intercompany pricing, a basis for dividend planning, and a defensible answer when the auditor or tax authority asks why the ledger speaks in one currency while the contract speaks in another. The cost of preparing that document is modest. The cost of reconstructing the rationale after the first set of consolidated accounts has been filed is not.