A branch office of a foreign bank operates in India, but it does not operate alone. Behind every branch is a head office — in New York, in London, in Tokyo — running the systems, carrying the compliance infrastructure, managing the executives, and allocating those costs across its global operations. Some portion of that burden lands on the Indian branch's books each year.

The question of how much India would accept as a deductible expense was, for decades, contested. The Income Tax Act answered it in Section 44C, but the answer turned out to be less clear than it looked. A reading of the provision had emerged — argued persuasively across many assessments — that allowed certain head office costs to escape the statutory ceiling entirely.

The Supreme Court's December 2025 decision in American Express Bank has closed that argument.

The Provision and the Interpretation It Generated

Section 44C was enacted to solve a specific problem. Assessing officers in India had no reliable means of verifying the costs a foreign head office claimed to have incurred in running its global operations. The risk of inflation was real and essentially undetectable from India. Rather than require case-by-case scrutiny of costs incurred outside the country, Parliament set a ceiling: head office expenditure deductible against Indian income is limited to the lower of 5% of adjusted total income, or the actual expenditure attributable to the Indian business.

The definition of "head office expenditure" — executive and general administration costs incurred outside India, common to all branches — contained a word that generated the dispute. That word was "common."

One reading of "common" is limiting: only costs shared across multiple jurisdictions fall within Section 44C's coverage. Costs incurred at the head office but attributable exclusively to the Indian branch — a manager posted solely to oversee Indian operations, a compliance officer whose entire role concerns the Indian business — are not "common" in that sense. They are India-specific. And if they fall outside Section 44C, they are deductible in full under the general provision in Section 37(1), unconstrained by the 5% ceiling.

American Express Bank divided its head office costs into two buckets on precisely this basis. Allocated costs — proportionate shares of general New York head office expenses — it placed within Section 44C. Specific costs — head office expenditure incurred wholly for the Indian branch — it claimed as ordinary deductions under Section 37(1). The Tax Department disagreed. The dispute worked its way to the Supreme Court.

Why the Court Read "Common" Broadly

The judgment adopts the broad reading, and the reasoning draws on three lines of analysis.

Textual: "common" describes the inherent character of head office administrative costs, not a precondition for inclusion. Executive salaries, rent, telephone, stationery, travel — these are not separable by destination with any reliability. The word is descriptive, indicating the class of cost, not a limiting filter that removes India-specific amounts from the provision's reach. Reading it as a limiting filter reintroduces, inside Section 44C itself, the very allocation exercise the provision exists to avoid.

Purposive: the inflation risk Section 44C was designed to address is highest precisely where the assessee draws the line between "common" and "exclusive-for-India." There is an obvious incentive to characterize as much expenditure as possible as India-specific — at which point it escapes the cap — while characterizing as common only those costs that, being proportionate shares of large global expenses, are individually small. A reading that permits this bifurcation empties the section of its content in exactly the cases where it is most needed.

Systemic: Section 44C is a specific provision covering its identified class of costs. Section 37(1) is the general deduction provision. Where a specific provision and a general provision meet the same category of expenditure, the specific provision governs. Head office administrative expenditure — whatever its origin within the head office structure — falls within Section 44C.

What Changes in Practice

The decision eliminates the bifurcation strategy. Foreign banks and non-resident entities with Indian branches that have been separating head office costs into "common" and "exclusive-for-India" buckets — and claiming Section 37(1) for the latter — now face a settled ruling against that approach. The ceiling operates on aggregate head office expenditure of the character Section 44C describes. The internal cost-center exercise of demonstrating exclusivity for India no longer changes the tax outcome.

Two things are unaffected. Treaty-level attribution principles continue to operate on their own terms, and the treaty position governs where it applies. Transfer-pricing analyses that address related-party transactions also remain separate — Section 44C concerns unilateral head office allocations, not arm's-length intercompany charges.

The Takeaway

For foreign banks and non-resident entities with Indian branches, the immediate task is a portfolio review. Assessments that have applied the narrow reading of "common" — either in self-assessment or in settled disputes — need to be revisited in light of the December 2025 ruling.

Pending assessments or appeals that rely on the bifurcation argument should be re-evaluated with candour: the Supreme Court has now settled the interpretive question. Continued reliance on the narrow reading will extend litigation without improving its prospects.

On a forward-looking basis, head office cost allocation policies need to be brought into line with the broad reading. The documentation exercise of establishing India-exclusivity for cost categories, previously directed at supporting a Section 37(1) deduction, no longer serves that purpose. Compliance resources are better redirected to the treaty and transfer-pricing frameworks, where genuine planning scope remains.