Assessment Year 2026-27 vs Tax Year 2026-27: Which ITR, Forms and Income-tax Act Apply?

The short answer

Assessment Year 2026-27 and Tax Year 2026-27 cover income earned during two different 12-month periods. They are governed by different income-tax laws.

• AY 2026-27 is for income earned from 1 April 2025 to 31 March 2026. It is governed by the Income-tax Act, 1961 and the ITR forms prescribed under that Act.
• Tax Year 2026-27 is for income earned from 1 April 2026 to 31 March 2027. It is governed by the Income-tax Act, 2025 and the Income-tax Rules, 2026.

The new Act took effect on 1 April 2026. This does not move income earned before that date into the new system. The old Act was repealed, but its savings provisions continue to govern returns, tax payments, assessments and other proceedings relating to earlier periods.

The practical rule is to choose the year that matches the period to which the income or tax obligation relates. Filing or paying tax after 1 April 2026 does not, by itself, mean you should select Tax Year 2026-27.

What do “financial year”, “assessment year” and “tax year” mean?

Under the Income-tax Act, 1961, the financial year runs from 1 April to 31 March. For income-tax purposes, that period was also called the previous year. The assessment year is the 12-month period immediately after the previous year, when income is reported and assessed.

That is why income earned in FY 2025-26 is reported in AY 2026-27. The return is generally filed after the financial year ends.

The Income-tax Act, 2025 uses tax year in place of the terms “previous year” and “assessment year” for periods beginning on or after 1 April 2026. Tax Year 2026-27 runs from 1 April 2026 to 31 March 2027. Its return is filed after the tax year ends, generally in 2027.

The new term aligns the year in which income is earned with the year used for that income period. It does not make AY 2026-27 and Tax Year 2026-27 two names for the same income.

Which Income-tax Act applies?

Income earned up to 31 March 2026

Use the Income-tax Act, 1961 for income earned during FY 2025-26 and earlier periods. This remains true even if you file the return, pay self-assessment tax or receive a notice after 1 April 2026.

For AY 2026-27:

• Select AY 2026-27 on the e-Filing portal.
• Use the ITR form and other forms prescribed for that assessment year under the old law.
• Apply the old Act’s provisions to FY 2025-26 income and deductions.
• Use the old Act for self-assessment tax payments and proceedings relating to that assessment year.

Income earned from 1 April 2026

Use the Income-tax Act, 2025 for income earned during Tax Year 2026-27 and later tax years. The new Act applies to income from 1 April 2026; it does not apply to earlier income just because a taxpayer deals with it after that date.

During the transition, the e-Filing portal supports compliance under both Acts. Depending on the service, it may ask you to select an assessment year or a tax year. Choose the one that matches the period and compliance you are completing.

Which ITR form should you use?

For AY 2026-27, use the ITR form prescribed under the Income-tax Act, 1961. The familiar return forms include ITR-1, ITR-2, ITR-3, ITR-4, ITR-5, ITR-6 and ITR-7. Your taxpayer type, income sources and form eligibility determine which one applies.

The Income-tax Rules, 2026 also prescribe ITR forms for Tax Year 2026-27. Form names such as ITR-1 and ITR-2 may look familiar, but use the form, schedules and instructions prescribed for the new Act and that tax year. Do not copy a return from AY 2026-27 or use an earlier utility without checking that it applies to Tax Year 2026-27.

The year is not the only factor in selecting a return. For example, some individuals with salary and specified other income may qualify for ITR-1. Capital gains, business income, foreign assets or other exclusions may mean a different form is required. HUFs and other entities also have separate form rules.

Check the instructions for the relevant year before filing. The form used for AY 2026-27 may not be the right version for Tax Year 2026-27.

What about other tax forms?

The transition affects forms beyond the income-tax return. Some forms remain applicable to old-law periods, while the new Act and Rules prescribe forms for Tax Year 2026-27.

These are examples, not a complete list of every form affected by the transition. Check the rules for the period covered by a deduction, declaration, certificate or report. Do not choose a form only because its name or purpose resembles a form you used previously.

Do you need to file two returns?

You do not file two returns for the same income because the law and terminology changed.

AY 2026-27 covers income earned before 1 April 2026. Tax Year 2026-27 covers income earned from 1 April 2026 to 31 March 2027. The return for the second period is filed after that tax year ends.

If you have a filing obligation for both periods, you may need to file a separate return for each period, in its own filing cycle and under the law that applies to it. They report different income periods; they are not duplicate returns for the same income.

For example, a salaried employee who earned income in FY 2025-26 files for AY 2026-27 under the old Act. If the employee also earns income in FY 2026-27 and is required to file, the later return will be for Tax Year 2026-27 under the new Act.

Which deadlines apply?

Deadlines depend on the taxpayer and return category. As of October 2026, several AY 2026-27 original filing deadlines have passed.

The general AY 2026-27 due dates included:

• 31 July 2026 for most individuals filing ITR-1 or ITR-2 and HUFs filing ITR-2.
• 31 August 2026 for specified non-audit business cases and trusts.
• 21 November 2026 for persons subject to audit in the specified category under Section 139(1). CBDT extended this return deadline from 31 October. The audit report deadline for those cases was extended to 21 October 2026.

Some categories, including certain transfer-pricing cases, have separate deadlines. Check the applicable statutory category and any CBDT extension before relying on a date.

A belated return for AY 2026-27 may generally be filed by 31 December 2026 or before completion of assessment, whichever is earlier. A late-filing fee under Section 234F may apply: ₹1,000 if total income does not exceed ₹5 lakh, and ₹5,000 in other cases.

A revised return for AY 2026-27 may generally be filed by 31 March 2027 or before completion of assessment, whichever is earlier. A revised return filed after 31 December 2026 may also attract the additional fee under Section 234-I: ₹1,000 if total income does not exceed ₹5 lakh, and ₹5,000 in other cases.

For Tax Year 2026-27, the return is filed after 31 March 2027. The scheduled deadlines are generally:

Check for official changes or extensions before filing. TaxClear’s guide to original, belated, revised and updated returns for AY 2026-27 explains return types and deadlines.

Which Act applies to tax payments?

The year and Act also matter when paying tax through the portal. A payment made after 1 April 2026 may still relate to AY 2026-27 and therefore fall under the Income-tax Act, 1961.

Advance tax installments for Tax Year 2026-27 are governed by the new Act. Self-assessment tax for an AY 2026-27 return remains under the old Act. The payment date alone does not decide which law applies; the period and tax obligation do.

TaxClear’s income-tax challan payment guide explains how to select the relevant Act and year. For Tax Year 2026-27 installments, see the advance tax guide.

What happens to notices, assessments and older returns?

The Income-tax Act, 2025 contains savings provisions for earlier periods. Returns, assessments, appeals, notices, reassessments, rectifications and other proceedings concerning a tax year beginning before 1 April 2026 continue under the Income-tax Act, 1961, even when the action takes place after that date.

For example, if you receive a notice in November 2026 about income reported in AY 2026-27, check the notice and respond under the provisions applicable to that assessment year. The new Act does not automatically apply because the notice arrived after 1 April.

Earlier assessment years also continue to use their year-specific forms and law. A revised or updated return for an earlier assessment year does not automatically move into the new Act.

The transition provisions preserve certain rights and obligations under the old law, including eligible loss carry-forwards, subject to the applicable conditions. Keep returns, payment challans, notices, responses and supporting records organized by assessment year or tax year.

How to choose the right year on the portal

Before starting a return or payment, use this checklist:

1. Identify the period to which the income or tax obligation relates.
2. For income earned from 1 April 2025 to 31 March 2026, select AY 2026-27.
3. For income earned from 1 April 2026 to 31 March 2027, use Tax Year 2026-27 for the relevant new-law compliance.
4. Confirm that the Act shown for the return, form or payment is correct.
5. Choose the form and utility prescribed for that period.
6. Check the applicable due date, including any taxpayer-specific extension.
7. Match tax payments and withholding credits to the correct period.
8. Save the acknowledgement, challans and e-verification confirmation.

The portal may display old and new law options at the same time. Take care when selecting a year for challans, tax forms, advance tax, self-assessment tax and return filing. TaxClear’s online ITR filing guide for AY 2026-27 outlines the filing process.

Examples

Employee filing in October 2026: Priya earned salary from April 2025 to March 2026. She selects AY 2026-27 and uses the form prescribed under the 1961 Act. She does not select Tax Year 2026-27 just because she is filing after 1 April. If she missed her original deadline, she should check whether she can file a belated return and whether a late fee applies.

Salary earned from April 2026 onward: Arjun’s salary for April 2026 to March 2027 belongs to Tax Year 2026-27. He keeps records for this period separately. The return is filed after the tax year ends using the form and utility prescribed under the new Act.

Self-assessment tax paid in October: Meena is paying a balance due on her AY 2026-27 return. Although she pays after the new Act took effect, the payment relates to FY 2025-26. She selects the Income-tax Act, 1961 and AY 2026-27 in the challan.

Audit forms filed after April 2026: A business’s audit relates to FY 2025-26. The audit report uses the applicable old-law forms, even if it is filed after 1 April 2026. The new audit form framework applies to the following tax year.

Frequently asked questions

Are AY 2026-27 and Tax Year 2026-27 the same?

No. AY 2026-27 relates to income earned in FY 2025-26. Tax Year 2026-27 relates to income earned from 1 April 2026 to 31 March 2027.

Which Act applies to my AY 2026-27 return?

The Income-tax Act, 1961 applies to income earned in FY 2025-26, even if you file the return, make a payment or receive an assessment notice after 1 April 2026.

Do I use a new ITR form for AY 2026-27?

No. Use the ITR form and schedules prescribed under the 1961 Act for AY 2026-27. The new Act and Rules apply to Tax Year 2026-27 and later periods.

Do I need to file both an AY return and a Tax Year return?

Not for the same income. If you have filing obligations for both periods, you may need separate returns for the income covered by each period and law.

Which Act applies to advance tax for Tax Year 2026-27?

The Income-tax Act, 2025 applies to advance tax for Tax Year 2026-27. Self-assessment tax for AY 2026-27 remains governed by the Income-tax Act, 1961.