Library / Income-tax Act, 2025: The Professional's Master Guide

Preface

On 1 April 2026, India began working under a new income tax law for the first-time in more than sixty years. For those of us who learnt the subject through sections like 43B, 44AD, 80C and 194J, the change is less about new rules and more about a new language. The principles we know remain; the numbers, the terms and the forms have changed.

This guide was written to be the one book a practising professional keeps on the desk during this transition and after it. It explains the Income-tax Act, 2025 in plain words, always showing the new section beside the old one, and it relies on worked illustrations rather than long commentary. Each illustration is built the way a working paper is built, with every step of the calculation visible.

The coverage runs from the basics of residence and the Tax Year, through each head of income, to the areas where most advisory work lies: corporate tax and MAT, mergers and restructuring, international taxation, transfer pricing, and the TDS and compliance cycle that finance teams handle every month. The appendices bring together the section mapping, the compliance calendar, practice questions and a checklist of common mistakes.

The law is stated as amended by the Finance Act, 2026. Where the new Act or the Rules leave room for interpretation, or where the position is still settling, the text says so. Suggestions and corrections from readers are welcome and will be taken into the next edition.

Vipin Nair

Ahmedabad, 28 September 2026