You can change your tax regime by filing a revised return under Section 139(5) of the Income Tax Act, but only if your original return was submitted on or before the due date under Section 139(1). Miss that deadline and you’re locked into the default new regime for the year, no matter what you do afterward. The switch itself is straightforward on the e-filing portal, but business income earners face a one-way rule that turns the decision into a serious one.1Income Tax Department. FAQs on New Tax vs Old Tax Regime
The On-Time Filing Rule Decides Everything
Before anything else, check when you filed your original return. For most individuals the Section 139(1) due date is July 31 after the end of the financial year. For taxpayers who need an audit or who have international transactions, it extends to October 31. File within that window and Section 139(5) lets you submit a revised return with a different regime selection.2Income Tax Department. Income Tax Act Section 139
A belated return under Section 139(4) cannot be used to opt for the old regime, even if you submitted Form 10-IEA before the deadline.1Income Tax Department. FAQs on New Tax vs Old Tax Regime You can still revise a belated return to fix errors, but revising it does not reopen the regime option you lost by filing late. This is where a lot of taxpayers get caught out. They assume the regime call can wait; it cannot.
One useful point for salaried readers: the regime you declared to your employer for TDS is not binding on your ITR. If your employer withheld under the new regime and the old regime works out cheaper for you, pick the old regime when you file, and switch again through a revised return if needed, provided the original was on time.
Salaried vs. Business Income: Very Different Freedom
Taxpayers without business or professional income get the most room to move. The Press Information Bureau has confirmed that individuals without business income can choose between the old and new regime afresh every financial year.3Press Information Bureau. Clarification Regarding Applicability of New Tax Regime and Old Tax Regime If your income comes only from salary, house property, capital gains, or other sources, you can pick either regime each year and revise within the deadline without consequence.
Business and professional income earners face a much stricter rule. Once you opt out of the new regime to claim the old, you get only one chance to switch back. After that switch back, the old regime is closed to you permanently. The Income Tax Department’s own FAQ puts it plainly: once you switch back to the new regime, “they won’t be able to choose old regime anytime in future.”1Income Tax Department. FAQs on New Tax vs Old Tax Regime If you have business income, run a full computation under both regimes and be certain before you submit the revised return. This is not a decision to make on a hunch.
The Revised Return Deadline and Fees
Budget 2026 extended the revised return deadline from December 31 to March 31 of the relevant assessment year, effective for AY 2026-27 onward. For a return covering FY 2025-26 (AY 2026-27), you have until March 31, 2027, or until the tax department completes assessment of your return, whichever comes first.4Government of India. Budget 2026-2027 Speech
The extra three months are not free. Revisions filed after December 31 of the assessment year now attract a nominal fee under the same Budget 2026 proposal:
- Income up to ₹5 lakh: ₹1,000 fee for revisions filed between January 1 and March 31.
- Income above ₹5 lakh: ₹5,000 fee for the same period.
Revisions filed on or before December 31 remain free.4Government of India. Budget 2026-2027 Speech Earlier is cheaper. The other hard stop is assessment: if the department completes processing before you file, the window closes even if the calendar date has not arrived.
What to Prepare Before You File
Form 10-IEA if You Have Business Income
If you earn from a business or profession and want to opt out of, or re-enter, the new regime, you must file Form 10-IEA electronically before or along with your revised return. This is the formal declaration that tracks your regime preference and any past switches.5Income Tax Department. Form 10-IEA FAQ Salaried individuals and others without business income do not file Form 10-IEA. They select the regime directly in the ITR form.6Income Tax Department. Form 10-IEA User Manual and FAQs
Proof for Old Regime Deductions
Switching to the old regime opens up Chapter VI-A deductions the new regime does not allow. Have the paperwork ready before you start the revised return. Section 80C covers items like life insurance premiums, PPF and ELSS investments, and tuition fees, with a limit of ₹1,50,000. Section 80D covers health insurance premiums up to ₹1,00,000 depending on your situation.7Income Tax Department. Deductions You will also want records for HRA exemption, home loan interest under Section 24, and any other exemption you plan to claim.
Recompute your tax under both regimes before you commit. A regime that looks better on paper can produce a worse result once interest under Sections 234A, 234B, and 234C is factored in. If the revised return shows lower advance tax liability than what you paid, you may be due a refund; if it shows more, pay the shortfall with interest before you file.
Your Original Return Details
Keep the 15-digit acknowledgement number from the original return handy. The filing portal uses it to link the revision to your original submission. You will also need your PAN and access to the mobile number registered with your Aadhaar or the e-filing portal for verification.
Filing the Revised Return on the Portal
Log in to the Income Tax e-filing portal and open the e-File section. Select “Income Tax Return” for the relevant assessment year. When asked for the filing type, choose “Revised Return” under Section 139(5). The portal will ask for the acknowledgement number and filing date of the original return.
From there, enter your revised income figures and select the tax regime you want. If you are moving to the old regime, the ITR form unlocks the deduction fields that were grayed out under the new regime. Fill in each deduction with the correct amount and supporting details. Review the tax computation screen to confirm the final liability or refund, then submit.
Verify Within 30 Days or the Filing Doesn’t Count
A revised return is not valid until it’s verified, and you have 30 days from the date of filing to complete e-verification.8Income Tax Department. ITR-V FAQs The fastest route is Aadhaar OTP, which sends a one-time password to the mobile number linked to your Aadhaar.9Income Tax Department. How to e-Verify User Manual You can also verify through a pre-validated bank account, demat account, or net banking. Miss the 30-day window and the return is treated as never filed, which undoes your regime change along with everything else in the revision.
After successful verification, the system generates a new acknowledgement and replaces the earlier return data with the revised figures. Refunds typically take four to five weeks to process after assessment. The updated status appears in your e-filing account within a few days of verification.
If You Missed the Revised Return Deadline
Section 139(8A) lets you file an updated return (ITR-U) within four years from the end of the relevant assessment year, a window Budget 2025 extended from the earlier two years. Do not count on this to change your regime. An ITR-U exists only to report additional income or correct underreporting; it cannot be used to reduce tax liability, claim or increase a refund, declare a loss, or change your regime selection.
It also carries an additional tax on top of what you owe: 25% within 12 months of the assessment year ending, 50% within 24 months, 60% within 36 months, and 70% within 48 months, plus interest. Only one ITR-U is allowed per assessment year, and it is unavailable if a search or survey has been initiated against you or if assessment or reassessment for that year is pending or complete. If the regime choice matters, treat the revised return deadline as the real deadline.
Rectification Is Not the Same Thing
A rectification under Section 154 is only for obvious clerical errors: an arithmetic mistake, a mismatch in TDS credit, an incorrect gender entry. It cannot change your income figures, add deductions you forgot to claim, or switch your tax regime. If the correction would change your taxable income, or if you want to change regime, you need a revised return under Section 139(5), not a rectification. Rectification also requires the original return to have been processed by the CPC first, while a revised return can go in as soon as you spot the issue.