What the 819→536 Section Consolidation Actually Means

The four mechanisms, confirmed directly from CBDT

incometax.gov.in's own FAQ on the Act's scope lists these explicitly:

1. Explanations and provisos folded into the main text. The 1961 Act often stated a rule, then added separate "Explanation" or "Proviso" clauses to clarify or carve out exceptions — sometimes several per section. The 2025 Act writes these directly into the section itself instead of as bolted-on afterthoughts, cutting the section count without cutting content.
2. Tables and formulas replace verbose narrative provisions. Where the old Act described a calculation or a set of conditions in dense prose, the new Act increasingly uses a table (an "Sl. No." row-based format that shows up across the Act, including in Section 58 below) instead — more compact on the page, same substance.
3. Redundant and obsolete provisions removed. Provisions superseded by later amendments, case law, or simply no longer relevant were dropped rather than carried forward as dead weight.
4. Clearer, more direct cross-references. Fewer indirect "refer to sub-clause (iii) of clause (a) of the Explanation to sub-section (2)"-style chains.

A concrete example: three sections become one

The clearest illustration CBDT gives is presumptive taxation. Under the 1961 Act, three separate sections covered it: Section 44AD (small businesses), Section 44ADA (professionals), and Section 44AE (goods transport). The 2025 Act consolidates all three into a single Section 58, laid out in tabular form — one row per category, rather than three separate sections repeating similar structure with different numbers. The presumptive income rates and turnover thresholds themselves are unchanged; only the drafting is different. This same pattern — several old sections collapsing into one new, often table-based section — repeats elsewhere in the Act; see the section concordance for more confirmed examples, including TDS provisions and return-filing sections.

What this does and doesn't mean for you

• Doesn't mean: a third of the tax rules were abolished, your deductions shrank, or the law got simpler to the point of needing less professional advice. The underlying substance is, per CBDT's own framing, unchanged — "without altering the underlying tax policy."
• Doesn't mean: everything you've learned about how tax works is obsolete. Rates, slabs, deduction caps, and eligibility rules carry over; see the Old vs New Tax Regime Calculator, unaffected by this renumbering.
• Does mean: if you (or your CA, or a form you're filling in) cite a specific section number for something under the new Act, it's very likely a different number than the one you're used to — sometimes because several old sections merged into it.
• Does mean: some material that used to be inline in a section may now live in a Schedule instead — worth checking a Schedule, not just the section text, if something you expect to find isn't where it used to be.

The Rules and Forms shrank even more, proportionally

The Income-tax Rules, 1962 had 511 rules and 399 forms. The Income-tax Rules, 2026 — notified alongside the new Act — have 333 rules and 190 forms: roughly a third fewer rules, more than half as many forms. The same consolidation logic applies: forms that did similar things under slightly different circumstances (see Form 10E vs Form 39 for one specific example) were often merged rather than each getting a direct 1:1 replacement.