Section 1 — Short Title Extent and Commencement

STATUTORY ARCHITECTURE — 18-ROW MAP

HISTORICAL CONTEXT — INDIAN INCOME-TAX LINEAGE

Indian income-tax has been a continuous legislative project since 1860. The original Income Tax Act, 1860 — enacted by the East India Company government to fund Mutiny-era expenditure — operated for five years before lapsing. The Income-tax Act, 1886 (post-Crown takeover) reintroduced income-tax on a more permanent basis. The Indian Income-tax Act, 1918 was a comprehensive reform; it was replaced by the Indian Income-tax Act, 1922 — the longest-lived predecessor — which governed Indian income-tax for four decades.

The Law Commission of India's Twelfth Report (1958), chaired by Justice K.N. Wanchoo, recommended a comprehensive replacement of the 1922 Act. The recommendations were incorporated into the Income-tax Bill which was enacted as the Income-tax Act, 1961 (Act 43 of 1961), receiving Presidential assent on 13-September-1961 and coming into force on 1-April-1962 per section 1(3). The 1961 Act introduced systematic improvements: (i) residence-based scope (sections 5, 6); (ii) five-heads architecture for computing income (section 14); (iii) coherent PGBP framework (sections 28-44); (iv) capital gains charge (section 45); (v) consolidated TDS framework (Chapter XVII).

Section 1 has been amended only minimally since 1962. The territorial-extent sub-section (s. 1(2)) was modified by the FA 2008 to remove the historic Sikkim exception (following the 36th Constitutional Amendment integration history); and by the Jammu & Kashmir Reorganisation Act, 2019 to formally extend the Act to the Union Territory of J&K and Ladakh from 31-October-2019. The Act now applies to the entire territory of India without exception.

Multiple attempts at comprehensive modernisation — Direct Tax Code 2009, 2010, 2013 — did not reach enactment. The Income-tax Act, 2025 (Act 30 of 2025), enacted following the Income-tax Bill, 2025 introduced in February 2025, finally succeeds the 1961 Act with effect from 1-April-2026. The 2025 Act introduces the 'tax year' terminology and consolidates several chapter structures, while preserving substantive principles. Section 536 of the 2025 Act is the operative saving clause — all proceedings, orders, notices, approvals, assessments under the 1961 Act continue to be governed by 1961 Act provisions even after 1-4-2026.

FINANCE ACT AMENDMENT TIMELINE (Section 1 itself)

■ 1-April-1962 — Section 1 came into force; original framework.

■ FA 2008 — Removal of historic Sikkim exception following 36th Constitutional Amendment integration.

■ Jammu & Kashmir Reorganisation Act, 2019 — Extension to J&K and Ladakh from 31-Oct-2019.

■ FA 1962 through FA 2025 — Section 1 itself substantively unchanged; surrounding architecture (charging, computation, machinery) has evolved through 60+ amending Finance Acts.

■ Income-tax Act, 2025 (Act 30 of 2025) — Comprehensive successor, effective 1-April-2026.

JUDICIAL EVOLUTION — VERIFIED LANDMARK AUTHORITIES

▸ Mathuram Agrawal v. State of Madhya Pradesh (1999) 8 SCC 667 ; (2000) 1 SCR 1 (Supreme Court)

Facts. A municipal levy was challenged on the ground that the charging provision did not clearly specify the rate, the persons charged, and the measure of tax.

Issue. Whether a tax can be imposed in the absence of a clear, unambiguous charging provision identifying the subject, measure, rate, and incidence.

HELD. Article 265 demands that tax be levied only by clear authority of law. The four components — taxable event, person, rate, and measure — must be clearly discernible from the charging provision; ambiguity is fatal to the levy.

“The intention of the Legislature in a taxation statute is to be gathered from the language of the provisions, particularly when the language is plain and unambiguous. In a taxing Act it is not possible to assume any intention or governing purpose other than what is given expression to.”

Relevance. Foundational authority on the rigour required of charging sections — underpins arguments that ambiguous deeming fictions, surcharge formulas, and rate prescriptions must be strictly construed.

▸ Commissioner of Income-tax v. Vatika Township Pvt. Ltd. (2014) 367 ITR 466 ; (2015) 1 SCC 1 (Supreme Court — 5-Judge Constitution Bench)

Facts. The Department sought to apply a surcharge provision retrospectively to block-period assessments. The assessee contended that the amendment was substantive and could not have retrospective operation absent express legislative direction.

Issue. Whether amendments to taxing statutes operate prospectively unless the legislature has expressly or by necessary implication conferred retrospective effect.

HELD. The Constitution Bench reaffirmed the general rule against retrospectivity of taxing statutes. A taxing provision must be construed prospectively unless the language compels otherwise; mere insertion or substitution by amendment is not sufficient to deny vested rights.

“Of the various rules guiding how a legislation has to be interpreted, one established rule is that unless a contrary intention appears, a legislation is presumed not to be intended to have a retrospective operation.”

Relevance. Anchor authority for any argument that an amendment to a charging or computational provision must apply only from the AY notified — useful in transitional disputes around FA 2025 and the 1961 → 2025 changeover.

▸ Calcutta Discount Co. Ltd. v. Income-tax Officer, Companies District I, Calcutta (1961) 41 ITR 191 ; AIR 1961 SC 372 (Supreme Court — Constitution Bench)

Facts. The assessee challenged a section 34 reassessment notice on the ground that the ITO had no jurisdictional foundation to reopen; the Revenue contended that the writ jurisdiction was ousted by the statutory appeals scheme.

Issue. Whether the High Court's jurisdiction under Article 226 is ousted by the existence of a statutory remedy where the reassessment notice itself lacks jurisdictional foundation.

HELD. Existence of an alternative statutory remedy does not oust Article 226 jurisdiction where the impugned action is wholly without jurisdiction. The burden is on the assessee to disclose all primary facts; the duty to draw inferences rests with the assessing officer.

“The duty of the assessee in every case is to disclose fully and truly all primary facts. Once all primary facts are before the assessing authority, he requires no further assistance by way of disclosure.”

Relevance. Foundational on the boundary between assessee's disclosure duty and the ITO's investigative duty — supports challenges to s. 147/148 (1961) / s. 281 (2025) reassessments on jurisdictional grounds.

▸ K.P. Varghese v. Income-tax Officer, Ernakulam (1981) 131 ITR 597 ; (1981) 4 SCC 173 (Supreme Court — 3-Judge Bench)

Facts. Section 52(2) (since deleted) deemed sale consideration to be FMV where FMV exceeded the declared consideration by 15%. The Department applied it on a literal reading even when the assessee had not in fact received more than the declared price.

Issue. Whether a deeming provision in a charging schema can be construed literally where its plain reading produces a result manifestly contrary to legislative object.

HELD. The Court read down section 52(2) to apply only where the assessee had actually received consideration in excess of the declared sum. A literal construction yielding absurd or unjust results must yield to an object-based interpretation; the CBDT's contemporaneous Circular No. 96 was held binding on the Revenue.

“It is well settled that a literal construction of a statutory provision ought not to be adopted if it produces a manifestly unjust result… Where a literal construction creates an anomaly, the courts will adopt that construction which avoids the anomaly.”

Relevance. Anchor authority for purposive construction of deeming fictions across the 1961 Act — applies wherever a deeming clause (e.g., s. 50C, s. 56(2)(x), s. 2(22)(e)) yields a result contrary to legislative purpose.

▸ Commissioner of Income-tax v. B.C. Srinivasa Setty (1981) 128 ITR 294 ; (1981) 2 SCC 460 (Supreme Court)

Facts. The assessee transferred goodwill of a self-generated nature. The Department sought to tax the consideration as capital gains; the assessee contended that no cost of acquisition could be ascertained, hence the computation provisions failed.

Issue. Whether capital gains arises where the asset has no ascertainable cost of acquisition — i.e., whether the charging provision can be invoked independently of a workable computation provision.

HELD. The charging section and the computation provisions form an integrated code; if the computation provisions cannot apply (because the cost is incapable of ascertainment), the charge itself fails. Self-generated goodwill is not taxable as capital gains.

“The charging section and the computation provisions together constitute an integrated code. When there is a case to which the computation provisions cannot apply at all, it is evident that such a case was not intended to fall within the charging section.”

Relevance. Anchor for the 'charge fails when computation fails' doctrine — useful in valuation impasses, self-generated assets, and computational ambiguity (though now largely overtaken by section 55(2)(a)(i) deeming cost as nil).

CBDT CIRCULARS — SECTION 1 ECOSYSTEM

▸ CBDT Circular No. 14(XL-35) of 1955 dated 11 April 1955

Subject. Duty of officers to assist assessees in claiming and securing relief

Substance. Foundational circular directing that the AO should not exploit assessee ignorance to deny legitimate reliefs; officer is required to draw attention to refunds or reliefs to which the assessee is entitled. The circular has been judicially noted in several appellate decisions and remains operative for first-appellate practice.

▸ CBDT Circular No. 549 dated 31 October 1989

Subject. Explanatory notes — Finance Act 1989 amendments (incl. PY unification)

Substance. Explained the FA 1987 / FA 1989 amendments unifying the previous year with the financial year preceding the AY, including transitional provisions for assessees with different accounting years. Useful in any controversy on the timing of accrual / chargeability for early post-1989 AYs.

▸ CBDT Circular No. 5 of 2014 dated 11 February 2014

Subject. Section 14A — dis-allowance even where no exempt income earned (since modulated)

Substance. Initially directed AOs to apply Rule 8D disallowance under section 14A even where no exempt income was earned in the year; subsequently modulated by Cheminvest (Del HC) and Maxopp (SC). FA 2022 amendment to section 14A re-asserted the position but remains under litigation.

WORKED EXAMPLES — TRANSITIONAL APPLICATIONS

PRACTITIONER PLANNING NOTES — SECTION 1

■ Maintain dual-framework competence during the 1961 → 2025 transition window (1-4-2026 onwards).

■ For AY 2025-26 and earlier — entirely 1961 Act regime; ITR forms / e-filing portal aligned.

■ For AY 2026-27 onwards — 2025 Act regime; transitional ITR forms anticipated.

■ Carry-forward positions — preserved across the transition; section 536 is the operative saving clause.

■ Pending appeals / assessments / reassessments — continue under 1961 framework.

■ Citation discipline — for 1961-Act matters, cite 1961-Act sections; for 2025-Act matters, cite 2025-Act sections.

■ 1961-Act case law — substantively continues under 2025 Act for sections with substantively identical language.

■ Practitioner library — retain Finance Acts 1962-2025 + 1961 Act + Income-tax Rules 1962 for residual / legacy matters.

■ Mapping discipline — 1961 → 2025 section mapping table essential for client briefing.

■ Constitutional anchor — Article 265 + Entry 82 of List I — argument framework for any constitutional challenge.

■ Article 246A (post-101st Constitutional Amendment) — GST framework — distinct from income-tax; do not confuse.

■ Article 269A — Inter-state trade and commerce levies — distinct from income-tax.

■ Black Money Act, 2015 — parallel statute on undisclosed foreign income; not subsumed by income-tax framework.

■ FEMA, 1999 — independent forex framework; coordinate income-tax compliance with FEMA.

■ Practitioner education — annual update circular on framework changes; especially around 1-4-2026 transition.

LITIGATION DEFENCE — SECTION 1 / TRANSITIONAL ARGUMENTS

■ Constitutional source — argue any income-tax demand must trace to Article 265 / Entry 82 / a valid Central Act (Finance Act + Income-tax Act).

■ Strict construction — Mathuram Agrawal anchor; tax cannot be imposed except by clear authority of law.

■ Retrospective application — Vatika Township anchor; any retrospective imposition must be express.

■ Saving-clause defence — section 536 (2025 Act) preserves 1961-Act framework for pending matters; defend against AO who applies 2025 Act provisions to 1961-Act-period assessments.

■ Transitional limitations — section 149 (1961 Act) time-bar — preserved through s. 536 for pending reassessments.

■ Calcutta Discount anchor — Article 226 writ jurisdiction not ousted by alternative remedy where impugned action is wholly without jurisdiction.

■ K.P. Varghese anchor — object-based interpretation across the transition; do not let AO produce absurd results through narrow reading.

■ B.C. Srinivasa Setty anchor — charge and computation form an integrated code; if 2025 Act computation provisions fail to capture a 1961-Act-period event, the charge itself fails.

■ Section 536 saving for licences / approvals — argue that 1961-Act approvals (e.g., 12A / 80G / 10(23C)) continue under 2025 Act regime.

■ Treaty continuity — DTAA agreements ratified under 1961-Act framework continue under 2025 Act; section 90 / 90A successor preserves.

■ Carry-forward preservation — argue against AO who denies carry-forward set-off across the transition.

■ ROR / NR classification — section 6 of 1961 / 2025 Act substantively identical; preserve prior classification.

■ Article 14 equality — argue against AO who applies one Act to similarly-situated assessees differently.

■ Article 19(1)(g) freedom of trade — argue against AO who applies tax inappropriately to restrict business.

■ Article 20(2) double jeopardy — no parallel charge for the same income under both Acts.

■ Article 265 ultra vires — argue against AO who applies tax beyond the Finance Act prescription.

PROCEDURE — APPLYING SECTION 1 IN PRACTICE

Step 1. Identify the relevant AY

Anchor every tax computation to its AY; that fixes the applicable Finance Act and the operative Act (1961 vs 2025).

Step 2. Identify the applicable framework

AY 2025-26 and earlier — 1961 Act + Finance Act of that year. AY 2026-27 onwards — 2025 Act + Finance Act 2026.

Step 3. Cite the correct section

1961-Act matters — cite 1961-Act sections; 2025-Act matters — cite 2025-Act sections. Use mapping tables where converting.

Step 4. Apply section 536 (2025 Act) for transitional matters

Pending proceedings / orders / notices / approvals under 1961 Act continue under 1961 Act provisions.

Step 5. Preserve carry-forward positions

Document carry-forward losses / depreciation / capital losses / VI-A deductions originating in 1961-Act years.

Step 6. Maintain treaty / approval continuity

DTAA / 12A / 12AB / 80G / 10(23C) / 197 approvals — preserve registration / certificate status across transition.

Step 7. Update ITR templates

AY 2026-27 returns will use new ITR forms; maintain mapping with 1961-Act-period data.

Step 8. Client briefing on transition

Brief HNI / corporate clients on regime change implications; carry-forward / capital-gains / deductions positions.

Step 9. Documentation discipline

Maintain 1961-Act-period working papers separately from 2025-Act-period; both required for compliance + litigation.

Step 10. Citation hygiene

Court / appellate authority decisions cite the Act version operative at the relevant time; ensure brief / written submission alignment.

Step 11. Constitutional source — preserve

Article 265 + Entry 82 + Article 14/19/20 — preserve for any constitutional challenge.

Step 12. Coordinate cross-statute compliance

GST / Customs / FEMA / Companies Act / SEBI — coordinate with income-tax compliance.

Step 13. Treaty-tie-breaker continuity

DTAA Article 4 tie-breaker — operates regardless of regime change; preserve TRC / Form 10F.

Step 14. Pending litigation status

Track appeals / writ petitions across the transition; ensure correct framework applied.

Step 15. Annual practitioner update

Update internal practice manuals around FA / 2025 Act developments; especially around 1-4-2026.

CROSS-REFERENCES

▸ Section 2 (1961) — Definitions.

▸ Section 3 (1961) — Previous year defined.

▸ Section 4 (1961) — Charge of income-tax.

▸ Section 5 / 6 (1961) — Scope + residential status.

▸ Section 9 (1961) — Income deemed to accrue or arise in India.

▸ Section 14 (1961) — Heads of income.

▸ Section 90 / 90A / 91 (1961) — DTAA framework.

▸ Section 115BAC (1961) — New regime for individuals / HUFs.

▸ Section 139 (1961) — Return of income.

▸ Section 147 / 148 / 148A (1961) — Reassessment.

▸ Section 246A (1961) — Appeals.

▸ Section 270A (1961) — Penalty under-reporting.

▸ Section 297 (1961) — Repeal of 1922 Act (predecessor saving clause).

▸ Section 1 (2025) — Successor short-title section.

▸ Section 1(3) (2025) — Commencement: 1-April-2026.

▸ Section 536 (2025) — Repeal & saving of 1961 Act.

▸ Income-tax Act, 1922 — Predecessor (repealed by 1961 Act).

▸ Income-tax Act, 2025 — Successor (Act 30 of 2025).

▸ Constitution — Article 265 (no tax except by authority of law).

▸ Constitution — Article 246A (GST framework — distinct constitutional source).

▸ Constitution — Article 269A (inter-state trade taxes).

▸ Constitution — Entry 82, List I (income other than agricultural income).

▸ Constitution — Article 14 (equality before law).

▸ Constitution — Article 19(1)(g) (freedom of trade / profession).

▸ Constitution — Article 20 (protection against ex post facto law / double jeopardy).

▸ Goa, Daman & Diu (Administration) Act, 1962 — Section 5.

▸ Sikkim Subjects Regulation, 1961 — Historical exception.

▸ J&K Reorganisation Act, 2019 — Territorial extension to J&K / Ladakh.

▸ Black Money (Undisclosed Foreign Income and Assets) Act, 2015 — Parallel statute on foreign-asset evasion.

▸ FEMA, 1999 — Foreign exchange framework.

▸ Companies Act, 2013 — Corporate compliance interface.

▸ Indian Partnership Act, 1932 — Firms / partnership framework.

▸ Limited Liability Partnership Act, 2008.

▸ Direct Tax Code drafts 2009 / 2010 / 2013 — Historical reform attempts.

▸ Finance Act 2025 — Last operative under 1961 Act framework for AY 2025-26.