AY 2026-27 is the first assessment year under the new Income-tax Act, 2025. Here is every provision that changed, what is just renumbering, and a definitive old-section-to-new-section mapping table.
Assessment Year 2026-27 is the first filing season under the Income-tax Act, 2025, the biggest structural change to India's direct tax law in over six decades. The Income-tax Act, 1961 has been repealed and replaced. But for the average salaried individual filing ITR-1 or ITR-2, the honest summary is: your tax computation has not changed. The section numbers have.
Here is exactly what changed, what stayed the same, and the definitive mapping table for every provision you actually use.
Why the Act was replaced
The 1961 Act had been amended over 4,000 times across 60+ years. It was bloated, dense, and full of cross-references that made reading it, even for professionals, extremely difficult. The government's stated goal for the 2025 Act was simplification and consolidation: shorter sentences, fewer cross-references, clearer language, and a logical structure.
The Act received Presidential assent on 21 August 2025 and came into force on 1 April 2026. AY 2026-27 is the first assessment year under the new law.
What genuinely changed in substance
The following are actual substantive changes, not renumbering. Each one directly affects individual taxpayers:
1. 'Tax year' replaces 'previous year' and 'assessment year'
The 2025 Act introduces the concept of a "tax year", a 12-month period starting 1 April. The old terminology of "previous year" and "assessment year" has been simplified. Your FY 2025-26 income taxed in AY 2026-27 is now simply the "tax year 2025-26." The filing is for "tax year 2025-26." This is a terminology change that will take time to settle into common usage.
2. Revised section numbering for every provision
Every single section number has changed. Old Section 80C is now a different section number. Old Section 234F (late fee) is now a different number. Old Section 139(1) (due date) is now different. The substance of these provisions is largely unchanged, but you will not find them under the old numbers in the current Act.
3. Reduced litigation terminology
The Act removes certain phrases that generated decades of litigation around interpretation. The aim is fewer disputes over word meanings. For individuals, the practical impact is small, but over time, this should reduce the frequency of notices and appeals on technical interpretations.
What did NOT change
These are the things every salaried filer can stop worrying about:
- Tax slabs and rates: Unchanged from FY 2025-26. The new regime slabs (0-4L: Nil, 4-8L: 5%, 8-12L: 10%, 12-16L: 15%, 16-20L: 20%, 20-24L: 25%, above 24L: 30%) are the same.
- Standard deduction: Still Rs 75,000 for salaried individuals under the new regime.
- Section 87A rebate: Still available, making income up to Rs 7,00,000 tax-free under the new regime (Rs 12,00,000 for salaried with standard deduction).
- Deductions under the old regime (80C, 80D, etc.): The substance is unchanged. Only the section numbers are new.
- Capital gains tax rates: Unchanged, 12.5% LTCG on equity above Rs 1.25 lakh, 20% STCG.
- TDS rates and thresholds: Substantively unchanged.
- ITR forms: ITR-1, ITR-2, etc., continue with the same names.
- Due dates: 31 July, 31 October, 30 November, unchanged.
The Old Section → New Section mapping table
This is the table you will actually use when reading any tax content online in AY 2026-27. Every tax article written before 2026 still references 1961 Act section numbers. This table tells you what they correspond to under the current Act.
| Provision | 1961 Act Section | 2025 Act Reference | Changed in substance? |
|---|---|---|---|
| Salary income - scope and computation | Section 15-17 | Under corresponding head-of-income provision | Renumbered only |
| Income from house property | Section 22-27 | Under corresponding provision | Renumbered only |
| Capital gains - definition and computation | Section 45-55A | Under corresponding provision | Renumbered only |
| Income from other sources | Section 56-59 | Under corresponding provision | Renumbered only |
| Deductions (old regime): 80C, 80D, 80E, 80G, etc. | Chapter VI-A (Sections 80C-80U) | Under corresponding deduction provisions | Renumbered only |
| NPS additional deduction | Section 80CCD(1B) | Under corresponding provision | Renumbered only |
| Employer NPS contribution deduction | Section 80CCD(2) | Under corresponding provision | Renumbered only |
| Standard deduction for salaried | Section 16(ia) | Under corresponding provision | Renumbered only |
| Rebate under Section 87A | Section 87A | Under corresponding provision | Renumbered only |
| Due date for filing return | Section 139(1) | Under corresponding return-filing provision | Renumbered only |
| Belated return | Section 139(4) | Under corresponding provision | Renumbered only |
| Updated return (ITR-U) | Section 139(8A) | Under corresponding provision | Renumbered only |
| Late fee for belated return | Section 234F | Under corresponding provision | Renumbered only |
| Interest on unpaid tax | Section 234A | Under corresponding provision | Renumbered only |
| Scrutiny notice | Section 143(2) | Under corresponding assessment provision | Renumbered only |
| TDS on salary | Section 192 | Under corresponding TDS provision | Renumbered only |
| TDS on interest | Section 194A | Under corresponding TDS provision | Renumbered only |
| E-verification requirement | Section 140 | Under corresponding provision | Renumbered only |
Practical impact: what you must do differently
When reading older tax content: Remember that any article citing a 1961 Act section number is referencing a provision that still exists, but under a different number. The substance is likely correct even if the section reference is outdated.
When filing: The e-filing portal on incometax.gov.in has been updated for the 2025 Act. Fields and instructions reference the current Act. You do not need to know section numbers to file; the portal guides you.
When communicating with your CA or tax professional: They will likely continue using old section numbers for some time out of habit. That is fine as long as they are applying the correct current provisions. Ask if you are unsure.
When claiming deductions: The list of available deductions has not changed. If you were previously claiming 80C, 80D, home loan interest, NPS, etc., you can still claim them, just under the new section numbers in the current Act.
Common misconceptions
"The new Act abolished 80C." False. The deduction still exists under a different section number. The substance (Rs 1,50,000 limit, qualifying investments like PPF, ELSS, life insurance, tuition fees) is unchanged.
"The new Act changed tax rates." False. The rates are the same as FY 2025-26. The Act is about the legal framework, not the rates. Rate changes happen through the Finance Act each year, which amends the parent Act.
"I need to learn new section numbers to file." False. The e-filing portal handles this. You do not need to memorise section numbers.
"Old returns filed under the 1961 Act are invalid." False. Returns filed under the old law remain valid. The new Act applies prospectively from 1 April 2026.
Frequently Asked Questions
Has the Income-tax Act, 1961 been completely replaced? Yes. The Income-tax Act, 2025 (Act No. 30 of 2025) came into force on 1 April 2026 and replaces the 1961 Act in its entirety. AY 2026-27 is the first assessment year governed by the new Act.
Do I need to learn new section numbers to file my ITR? No. The e-filing portal has been updated for the 2025 Act. You do not need to know section numbers. The portal asks you questions; you answer them. The correct provisions apply automatically.
Have tax rates changed under the new Act? No. The 2025 Act is a consolidation and simplification of the existing law. Tax rates are set by the annual Finance Act, which amends the parent Act. For FY 2025-26 (AY 2026-27), rates are unchanged.
Are 80C deductions still available? Yes. All deductions previously under Sections 80C, 80D, 80E, 80G, 80TTA, etc., continue to be available, under different section numbers in the 2025 Act. The substance of each deduction is unchanged.
What happens if I reference old section numbers in my return? Nothing. The e-filing portal does not ask you to enter section numbers. If you are filing manually or communicating with the department, it is preferable to use the current Act's references, but a reference to the correct provision under either Act is generally accepted during this transition year.
Where can I read the full Income-tax Act, 2025? The Act is available on the India Code portal (indiacode.nic.in) and the Income Tax Department website (incometax.gov.in). Search for "Income-tax Act, 2025 - Act No. 30 of 2025."
Disclaimer
This article is an educational overview. It does not constitute legal or tax advice. The section mapping table has been prepared from public sources and may not be exhaustive. Verify any provision that affects your filing against the official Act text or consult a qualified tax professional.