Old vs New Section Numbers Under the Income-tax Act 2025: The Mapping That Matters

Section 80C is now Section 123. Tax audit moved from 44AB to 63. Return filing went from 139 to 263. The Income-tax Act, 2025 compressed 819 sections into 536, and from 1 April 2026 the new numbers are the law. This page is the cross-reference — the sections and forms you will actually meet, in two clean tables, plus how to read old references in notices during the transition.

One thing before the tables. The renumbering changed addresses, not substance. The 80C limit is still ₹1.5 lakh. The audit thresholds are still ₹1 crore and ₹50 lakh. If you want the full story of what changed and what did not, start with our pillar guide to the Income-tax Act 2025 vs the 1961 Act.

And a note on when each set of numbers applies. The new numbers govern income from tax year 2026-27 onwards (from 1 April 2026) and all forms filed from that date. The old numbers continue to govern every year up to FY 2025-26 — including the return you file during 2026. Bookmark this page; you will be translating in both directions for a while.

Section mapping: 1961 Act → 2025 Act

1961 Act	2025 Act	Subject
6	6	Residential status (keeps its number)
10 (exemptions)	11 (with Schedules II–VII)	Incomes not included in total income
44AA	62	Books of account
44AB	63	Tax audit
44AD / 44ADA / 44AE	58 (single section)	Presumptive taxation, residents
44B / 44BB / 44BBA / 44BBB	61	Presumptive taxation, non-residents
54	82	Capital-gains exemption — sale of residence
54B	83	Capital-gains exemption — agricultural land
54EC	85	Capital-gains exemption — specified bonds
54F	86	Capital-gains exemption — investment in a house
80C / 80CCC / 80CCE	123 (with Schedule XV)	LIC / PF / ELSS deduction (₹1.5 lakh limit unchanged)
80CCD	124	NPS contributions
80D	126	Health insurance
80E	129	Education-loan interest
80G	133	Donations
80-IAC	140	Startup tax holiday
80TTA / 80TTB	153	Interest on deposits
87	155	Rebate computation
87A	156	Rebate (up to ₹60,000; ₹12 lakh income, unchanged)
90 / 90A	159	DTAA relief
115BAA	200	22% domestic-company option
115BAC	202	New (default) tax regime
139	263	Return of income
139A / 139AA	262	PAN / Aadhaar
140A	266	Self-assessment tax
140B	267	Updated-return tax (48-month window)
192 (salary TDS)	392	TDS on salaries
194-series & 195 (all non-salary TDS)	393 (table-based)	393(1): payments to residents; 393(2)/(3): payments to non-residents
197	395	Lower / nil TDS certificates

Three patterns in this table are worth noticing, because they explain most of the new Act's structure. First, the deduction chapter was renumbered as a block: the old 80-series now lives in the 120s to 150s, in roughly the same order. Second, several old sections merged — the three presumptive schemes (44AD, 44ADA, 44AE) became one Section 58, and the entire non-salary TDS family became one Section 393, with the rate and threshold for each payment type sitting in a table inside the section rather than in a separate section per payment. Third, where the old Act used suffixes (115BAA, 115BAC), the new Act uses clean consecutive numbers (200, 202). Once you see the patterns, the new map is easier to hold in your head than the old one ever was.

Form mapping: old forms → new forms (from 1 April 2026)

Old form	New form	Purpose
Form 13	Form 128	Application for lower / nil TDS certificate (under s.395)
Form 15CA	Form 145	Remitter's declaration for foreign remittance
Form 15CB	Form 146	CA certificate for taxable foreign remittance above ₹5 lakh per FY
Form 16	Form 130	Salary TDS certificate
Form 26AS	Form 168	Annual tax statement
Form 24Q	Form 138	Quarterly salary-TDS statement
Forms 26QB / 26QC / 26QD / 26QE	Form 141	Single challan-cum-statement for TDS under s.393(1) (property, rent, contractors, VDA)
Form 10F	Form 42	Non-resident treaty-relief particulars (with TRC)
Form 10E	Form 39	Arrears relief (new s.157, old s.89)

Two transition notes on forms. Old Forms 15CA/15CB filed for remittances completed on or before 31 March 2026 remain valid. And for the return you file in 2026 (AY 2026-27), the familiar ITR-1 to ITR-7 continue, because that filing is still under the 1961 Act.

How to read old references during the transition

For the next several years you will see both numbering systems in the wild. Three rules keep you oriented:

1. Date the document, then pick the Act

Ask one question first: which year of income does this relate to? Anything up to FY 2025-26 lives under the 1961 Act, so old section numbers are correct on it — a 2027 assessment notice for AY 2025-26 will rightly quote Section 143, not a new number. Anything from tax year 2026-27 onwards should quote the 2025 Act.

2. Old certificates and registrations do not lapse by renumbering

A Section 197 certificate, an 80G approval, a 12A registration — these were issued under the 1961 Act and the new Act's repeal-and-savings framework preserves what was validly done under the old law. The renumbering alone does not invalidate them. Where fresh applications are made from 1 April 2026, they cite the new sections and forms.

3. Watch for mixed references in the transition year

During 2026 the systems deliberately overlap: TDS deducted from April 2026 falls under Sections 392/393 and the new forms, while the return being filed in the same months is an old-Act return for AY 2026-27. A salary slip quoting Section 392 and a tax return quoting Section 139 can both be correct on the same day. The mechanics are walked through in our guide to filing your first return under the new Act; NRIs should also see the NRI-specific renumbering guide.

When a client forwards a notice, the first thing we check is not the section number — it is the year. The year tells you which Act the number belongs to.

4. Translate carefully where sections merged

One-to-one renumbering is mechanical: 80D is 126, full stop. Merged sections need more care. If your old reference is "44ADA", the new reference is Section 58 — but you then need the right limb of Section 58, because it now houses three former schemes. Likewise, "TDS under 194-IA" becomes "TDS under Section 393(1)" plus the relevant row of the table. When updating engagement letters, board resolutions, loan covenants or software configurations, translate to the sub-section and table row, not just the section number.

Keep the map handy, but verify the substance

A mapping table answers "where did it go". It does not answer "does it still apply to me" — thresholds, conditions and elections still need to be read in the new text, especially where several old sections merged into one (the presumptive schemes into Section 58, the TDS family into Section 393). And remember which documents need updating on your side: standing instructions to banks that cite 195, payroll software that prints 192 on payslips, rent agreements that reference 194-I. None of these break overnight, but each will eventually confuse someone if left untranslated. For business and personal positions that turn on the detail, our taxation practice works with both Acts daily and can map your specific references.

Received a notice or document and not sure which Act it speaks? Send it across — the firm will place it for you.