Income Tax Act 2025: What Actually Changes for You

Why there is a new Act at all

The Income-tax Act, 1961 ran for over six decades. In that time it was amended more than four thousand times, sections were inserted, deleted and renumbered inconsistently, and the language grew dense with cross-references. Reading it had become a specialist skill in itself.

The Income Tax Act, 2025 is the government's answer: a clean rewrite that keeps the substance but simplifies the structure. It takes effect from 1 April 2026. The stated aim is easier reading, fewer disputes and simpler compliance, not more tax. That distinction matters, so it is worth being clear up front about what does not change.

What stays exactly the same

Before the changes, here is what carries over untouched, so you can stop worrying about the parts that matter most to your wallet:

• Tax rates and slabs. The Budget 2026 slabs stand. The new regime under the renumbered equivalent of Section 115BAC remains the default.
• Deduction limits. The ₹1.5 lakh cap that everyone knows as 80C continues. Health-insurance limits of ₹25,000 and ₹50,000 continue. Every limit is carried forward as-is.
• The Section 87A rebate that makes income up to ₹12 lakh effectively tax-free under the new regime continues.
• PAN, TAN and faceless assessment remain valid and unchanged. You do not reapply for anything.
• Filing deadlines. The compliance calendar is the same, 31 July for most non-audit individuals, with the usual staggered dates for audit and business cases.

In short, if you only care about how much tax you pay, the answer is: the same as before. The reform is about how the law reads, not what it costs you.

The big change: "Tax Year" replaces FY and AY

For decades, Indian taxpayers have juggled two confusing terms. The Financial Year (FY) was when you earned the income. The Assessment Year (AY) was the following year, when that income was assessed and the return filed. Earning in one year and being assessed in another tripped up almost everyone at some point.

The Income Tax Act 2025 replaces both with a single concept: the Tax Year. Tax Year 2026-27 simply means the period from 1 April 2026 to 31 March 2027, the income earned and reported for that window. One term, no gap, far less confusion.

You will still see FY and AY referenced for older years, because income earned up to 31 March 2026 continues to be handled under the old framework. But from April 2026 onward, "Tax Year" is the language to learn.

Section renumbering: the ones you know

This is the change professionals and regular filers will feel most. The deductions and provisions are the same; their addresses in the law have moved. Here are the ones most people recognise:

All the familiar 80C investments, PPF, ELSS, life insurance, NSC, Sukanya Samriddhi, five-year tax-saving deposits, tuition fees and home-loan principal, now sit together in Schedule XV rather than being scattered through the section. It is a tidier home for the same list.

The practical risk is not financial, it is clerical. Payroll systems, tax software, investment declarations and even the wording of notices will reference the new numbers from April 2026 onward. If you handle your own compliance, keep a section-mapping reference handy so an old-number habit does not cause a new-number error. Our income tax and ITR filing service already works to the correct references for whichever year applies.

The transition timeline: which Act applies when

This is where most confusion lives, so read it slowly. Two Acts run in parallel during the changeover, and which one applies depends entirely on when the income was earned, not when you file.

• Income earned up to 31 March 2026 (FY 2025-26, AY 2026-27) is governed by the old Income-tax Act, 1961. Your July 2026 return uses the old section numbers. This is effectively the last filing season under the familiar 1961 framework.
• Income earned from 1 April 2026 (Tax Year 2026-27) is governed by the new Income Tax Act, 2025. The first return under the new Act, with new section numbers and Form 130, will be filed from July 2027.

For businesses, the cleanest approach through the changeover is a clear demarcation of income, expenses, TDS and advance tax between the two years, and separate reconciliation of each year's tax statement. If that sounds fiddly, it is exactly the kind of thing worth handing to a professional for the transition year.

What you should do now

For most individuals, the honest answer is: very little, beyond being aware. But a short checklist keeps you clear:

• File your AY 2026-27 return normally, using old section numbers. Nothing about your July 2026 filing changes.
• Learn the handful of new numbers that affect you, especially 80C to 123 and 80D to 126, so next year's declarations and any notices make sense.
• If you run payroll, confirm your system is being updated to the new section numbering and Form 130 for periods from April 2026.
• If you use tax software or maintain books, update your statutory references and templates for Tax Year 2026-27.
• Keep a mapping reference of old-to-new sections for the transition period, or work with a CA who already has one.

The reform is designed to make tax simpler over time. The friction is concentrated in this one transition year, when both systems coexist and it is easy to quote the wrong number. Getting that year right, cleanly reconciled and correctly referenced, is where a Chartered Accountant earns their fee.

Quick answers

Will my tax go up because of the new Act? No. Rates, limits and rebates are unchanged. Has 80C been removed? No, its subject matter is now in Section 123, same ₹1.5 lakh benefit. Which Act applies to my July 2026 filing? The old 1961 Act, because it covers income earned up to March 2026. When does the new numbering first apply to a return? From Tax Year 2026-27, filed in July 2027. If you would rather not track any of this, our ITR filing service handles the right references for you.