The Income Tax Act operates on the principle that income earned in one year (previous year) is assessed and taxed in the following year (assessment year). This time-lag system allows the government to assess total annual income after the year ends.
Legal Framework
| Provision | Content |
|---|---|
| S.3 | "Previous year" means the financial year immediately preceding the assessment year |
| S.2(9) | "Assessment year" means the period of 12 months commencing on 1st April every year |
| S.4 | Income tax charged in respect of total income of the previous year |
| S.172 | Shipping income: assessment in PY itself (exception) |
| S.174 | Assessment of persons leaving India: AO can assess before year ends |
| S.174A | Assessment of AOP/BOI formed for particular event |
| S.175 | Assessment of persons likely to transfer property to avoid tax |
| S.176 | Discontinued business: assessment in current year |
Core Concepts
| Term | Definition | Example (FY 2025-26) |
|---|---|---|
| Previous Year (PY) | Financial year in which income is earned | 1 April 2025 to 31 March 2026 |
| Assessment Year (AY) | Financial year in which income of PY is assessed and taxed | 1 April 2026 to 31 March 2027 |
| Financial Year | 1 April to 31 March | Fixed by calendar |
| Uniform PY | Since 1989, all assessees have the same PY (April-March) | Universal applicability |
Why: The PY-AY system exists because income for a full year must be computed before it can be assessed. Assessment cannot happen during the earning year because the total is unknown until March 31.
Relationship Between PY and AY
| Scenario | PY | AY |
|---|---|---|
| Salary earned in FY 2025-26 | 2025-26 | 2026-27 |
| Business started on 1 Oct 2025 | 2025-26 (from 1 Oct to 31 Mar) | 2026-27 |
| Capital gain on 15 Jan 2026 | 2025-26 | 2026-27 |
| Return filing deadline (non-audit) | 31 July 2026 | |
| Return filing deadline (audit cases) | 31 October 2026 |
Exceptions: Assessment in Previous Year Itself
In certain cases, income is assessed in the PY itself (departure from normal rule):
| Section | Situation | Reason |
|---|---|---|
| S.172 | Non-resident shipping income | Ship may not return to India |
| S.174 | Person leaving India with no intention to return | Recovery becomes impossible |
| S.174A | AOP/BOI formed for specific event about to dissolve | Entity ceases to exist |
| S.175 | Person likely to transfer/charge property to avoid tax | Anti-avoidance measure |
| S.176 | Business discontinued during PY | No entity to assess next year |
Why: These exceptions exist because the normal PY-AY system assumes the assessee will be available for assessment in the following year. Where this assumption breaks down (person leaving, entity dissolving), the AO must assess immediately.
First Previous Year for New Business/Profession
If a business or source of income comes into existence mid-year:
| Situation | Previous Year |
|---|---|
| Business started 1 July 2025 | 1 July 2025 to 31 March 2026 |
| House property acquired 1 Nov 2025 | 1 Nov 2025 to 31 March 2026 |
| Employment started 15 Feb 2026 | 15 Feb 2026 to 31 March 2026 |
From the second year onwards, the PY is always the full financial year (April-March).
Recall Check
- What is the previous year for AY 2026-27?
- In which situations can income be assessed in the previous year itself?
- What is the previous year for a business started on 1 October 2025?
Key Cases
CIT v. Girdhari Lal (1961) CIT-v-Girdhari-Lal-1961 Issue: Whether assessment can relate only to a complete previous year or also to part of it. Rule: S.3 (as it then stood) allowed different previous years for different sources; since uniformity was introduced, PY is always the financial year. Held: The previous year concept is statutory. Income of any source accruing during the PY is assessable in the immediately following AY. The AO cannot go behind the statutory PY to a different period.
Distinctions
| Feature | Previous Year | Assessment Year |
|---|---|---|
| Purpose | Year of earning income | Year of assessing and paying tax |
| Period | 1 April to 31 March | 1 April to 31 March (following year) |
| Section | S.3 | S.2(9) |
| Activity | Income accrues/is received | Return filed, assessment made, tax paid |
| Tax rate | Not applicable (income is computed) | Rates of Finance Act of this year apply |
| Example | FY 2025-26 | AY 2026-27 |
Flashcards
Q: Define "Previous Year" under S.3. A: The financial year immediately preceding the assessment year, i.e., the year in which income is earned.
Q: Define "Assessment Year" under S.2(9). A: The period of 12 months commencing on 1st April every year, in which income of the preceding PY is assessed.
Q: What is the PY for AY 2026-27? A: FY 2025-26 (1 April 2025 to 31 March 2026).
Q: Name three exceptions where income is assessed in the PY itself. A: S.172 (shipping), S.174 (person leaving India), S.176 (discontinued business).
Q: Why was the uniform PY system introduced? A: To simplify administration; earlier, different assessees could have different previous years, causing confusion.
Q: What is the first PY for a business started on 1 November 2025? A: 1 November 2025 to 31 March 2026.
Exam Scenario
A foreign national working in India decides to permanently leave India on 15 December 2025 and has no assets in India. The AO wants to assess his income for the period April-December 2025 immediately. Is this permissible?
Approach: Under S.174, where a person is about to leave India with no present intention of returning, the AO may assess the total income up to the date of departure during the current PY itself. The normal PY-AY rule is an exception here. The AO can complete assessment on income from 1 April to 15 December 2025 without waiting for AY 2026-27. This prevents loss of revenue where recovery would become impossible.