Short Title and Commencement

Rule 1 — Short Title and Commencement

Rule 1 of the 2026 Rules mirrors Rule 1 of the 1962 Rules verbatim apart from the change of year and date. The Rules are subordinate legislation issued by the CBDT under section 533 of the 2025 Act (corresponding to section 295 of the 1961 Act). The 1 April 2026 commencement aligns the Rules with the parent Act so that every rule is operative when the Act first comes into force; there is no interregnum during which the Act is in force without supporting Rules.

Source of authority. Section 533 of the 2025 Act empowers the CBDT to make rules "for carrying out the purposes of this Act". The exercise of this power must be intra vires — within the Act's framework — and procedurally compliant: under the parent Act, every rule must be laid before each House of Parliament for a session of thirty days, during which time both Houses may modify or annul. This procedural safeguard (corresponding to section 296 of the old Act) is preserved through the procedural provisions in Chapter XXIII of the new Act.

Continuity of validity-of-Rules jurisprudence. Every Rule under the 1962 framework was challenged from time to time as ultra vires the parent Act; the canonical approach was set by the Supreme Court in CIT v. S. Chenniappa Mudaliar (1969) 74 ITR 41 (SC) — Rules cannot enlarge the scope of the Act, but may operationalise what the Act permits. The same principle applies to the 2026 Rules: any Rule that purports to charge tax on an item not within the Act's charging architecture would be void; any Rule that fixes a procedural mechanism within the Act's grant of rule-making power is valid.

Practical takeaway. (i) For all working papers, opinion notes and audit reports prepared on or after 1 April 2026, cite "Rule [N] of the Income-tax Rules, 2026" instead of "Rule [N] of the Income-tax Rules, 1962". (ii) For periods up to 31 March 2026 — the old Rules continue to govern under the savings clause in section 536 of the 2025 Act read with the parallel provision in the 2026 Rules. (iii) Pending notifications, Forms and instructions issued under the 1962 Rules survive the transition and are deemed to have been issued under the corresponding provisions of the 2026 Rules — until rescinded.