Section 80C is now Section 123: the full deduction mapping

Short answer: Section 80C is now Section 123. The whole of Chapter VI-A moves to sections 122–154 of the Income-tax Act, 2025. Limits and eligibility are unchanged. The catch is that under the default regime (Section 202), most of these deductions are not available to you at all — so knowing the new number matters less than knowing which regime you are in.

The headline mapping

The complete Chapter VI-A concordance

Two entries are worth pausing on, because a mechanical one-to-one lookup misses both:

• 80TTA and 80TTB have merged into a single Section 153. Searching for a separate senior-citizen provision will not turn one up.
• Section 10AA has moved chapters. It was an exemption under the 1961 Act and is now a deduction at Section 144. If you are scanning the old Chapter VI-A range for it, you will not find it.

⚠️ The part most mapping tables leave out

Knowing that 80C is now 123 is close to useless on its own, because under the default regime most of these sections are not available to you.

The regime under Section 202 (the old Section 115BAC) is the default. It offers lower slab rates in exchange for giving up almost all the deductions in the table above.

Section 202(2)(a)(xii) states the exception precisely. Under the default regime, total income is computed without any deduction under Chapter VIII — other than Section 124(1) and 124(2) (pension scheme contributions), Section 125(2) (Agnipath Scheme) and Section 146 (additional employee cost). Those three are the entire surviving list. Section 123, Section 126, Section 133, Section 134 and the rest do not apply.

Outside Chapter VIII, the ₹75,000 standard deduction from salary survives — Section 19(1) of the Table at Sl. No. 2 sets it at ₹75,000 "where income-tax is computed under section 202(1)", against ₹50,000 in any other case.

What you do lose from the salary head is professional tax. Section 19(1) Sl. No. 1 allows the employment tax levied under Article 276(2) of the Constitution, and Section 202(2)(a)(iv) expressly excludes it under the default regime.

So the real question is never "what is 80C called now". It is which regime leaves you paying less — and that is an arithmetic question about your own numbers, not a lookup. We work through it in old vs new tax regime under the Income-tax Act 2025.

Which year uses which numbering

This is the error we see most often, and it runs in both directions.

Filing your FY 2025-26 return after 1 April 2026 does not move it to the new Act. The year the income was earned decides, not the date you file. Pre-2026 proceedings lawfully continue under the old Act and its numbering — see does the Income Tax Act 2025 change your FY 2025-26 return?.

Where to go next

For the sections outside Chapter VI-A — capital gains, TDS, assessment, appeals — the full old-to-new section mapping is the quick reference. For what changed in substance rather than numbering, see Income Tax Act 2025 vs 1961.

This is a working reference, not the statute. For anything you are filing or relying on, confirm the section text against the Act or the department's official 1961-vs-2025 comparison utility.