Form 10IE Old vs New Regime Switch: Rules for Salaried vs Business Income FY 2025-26

Most taxpayers still believe they need to file Form 10-IE to choose between the old and new tax regimes. That form is dead. The Central Board of Direct Taxes (CBDT) replaced it with Form 10-IEA through Notification No. 43/2023 dated 21 June 2023, the same week the new regime became the default under Section 115BAC(1A) of the Income Tax Act 1961. For Financial Year 2025-26 (Assessment Year 2026-27), whether you ever touch Form 10-IEA depends on a single fact: do you have income from business or profession, or only salary, house property, capital gains, or other sources? Get this wrong and you can lose the old regime forever, or worse, file a defective return that triggers a Section 139(9) notice within 15 days.

This Q&A walks through the exact statutory mechanics, a worked example using the income tax calculator, and seven follow-up scenarios our readers ask most often. Every number is taken from the IT Act, the latest CBDT notification, or the Finance Act 2025.

The Scenario

Rohan earns Rs 18 lakh a year as a salaried product manager in Bengaluru. His wife Priya runs a freelance UX design practice booking Rs 14 lakh a year on a presumptive basis under Section 44ADA. Both filed under the old regime for AY 2024-25 (FY 2023-24) because their combined Section 80C, 80D, HRA, and home loan interest exceeded Rs 4.5 lakh.

For FY 2025-26, the new regime looks more attractive on paper because the rebate under Section 87A is now Rs 60,000 with the threshold raised to Rs 12 lakh by the Finance Act 2025, the standard deduction is Rs 75,000, and the highest surcharge is capped at 25 per cent. They want to know: can they both simply tick the new regime in ITR-1/ITR-3 next July, or does Priya have to file a separate form? And if Priya switches once, can she ever come back to the old regime if her freelance income shrinks?

This is the textbook fact pattern for Form 10-IEA confusion. The answer differs sharply for each spouse, and the consequences last a lifetime for one of them.

Statutory Answer

The entire framework sits in Section 115BAC of the Income Tax Act 1961, as substituted by the Finance Act 2023 and tweaked by the Finance Act 2025. Three sub-sections do the work.

Section 115BAC(1A) - the new default

From AY 2024-25 onwards, the concessional regime under Section 115BAC(1A) applies automatically to every individual, Hindu Undivided Family (HUF), Association of Persons (AOP, other than a co-operative society), Body of Individuals (BOI), and Artificial Juridical Person. You do not file any form to be in the new regime. Silence equals consent.

Section 115BAC(6) - opting out

A taxpayer may exercise the option to be taxed under the old regime only by furnishing a statement in Form 10-IEA (Rule 21AGA of the Income Tax Rules 1962) on or before the due date specified in Section 139(1) for filing the return. Two distinct rules apply:

The lock-in trap for business income

The second proviso to Section 115BAC(6) is brutal. Once a taxpayer with business or professional income files Form 10-IEA to opt out of the new regime, they may withdraw that option only once in their lifetime by filing Form 10-IEA again (this time to re-enter the new regime). After that withdrawal, they are barred from ever opting out again - unless they completely cease to have business or professional income in a future year.

The due date matters as much as the form. Filing Form 10-IEA even one day after the Section 139(1) deadline (31 July 2026 for non-audit individuals, 31 October 2026 for tax-audit cases) is fatal: the option is treated as never exercised and the return is processed under the new regime, often producing a refund mismatch and a CPC intimation under Section 143(1).

Worked Resolution

Rohan (salaried only) - no Form 10-IEA needed

For FY 2025-26, Rohan's gross salary is Rs 18,00,000. He has Rs 1,50,000 of Section 80C investments and Rs 25,000 of Section 80D health insurance premium for himself and his parents.

The new regime saves Rohan Rs 91,000. He simply selects 'New Tax Regime u/s 115BAC' in the regime drop-down inside ITR-1 (or ITR-2) when he files in July 2026. He files no separate form. Next year (FY 2026-27) he can switch back to the old regime if home loan interest under Section 24(b) suddenly tilts the maths. Cross-check the working with the old vs new regime calculator before filing.

Priya (presumptive professional) - Form 10-IEA mandatory

Priya declares Rs 7,00,000 as profit (50 per cent of Rs 14,00,000 gross receipts) under Section 44ADA. She has Rs 1,50,000 of 80C investments and a Rs 50,000 NPS Tier-I contribution she has been claiming under Section 80CCD(1B). The Rs 50,000 deduction under 80CCD(1B) is NOT allowed in the new regime under Section 115BAC; it remains available only in the old regime.

For FY 2025-26 both regimes leave Priya at zero tax (she falls within the Rs 12 lakh rebate ceiling under the new regime and the Rs 5 lakh ceiling under the old). The financial difference is nil, but a procedural gap is enormous.

If Priya wants the old regime - perhaps to keep the NPS habit and the 80C discipline visible on her ITR for loan applications - she must file Form 10-IEA on the e-filing portal on or before 31 July 2026. The form asks for:

1. PAN, name, address
2. Nature of business or profession
3. Whether opting in or opting out
4. The assessment year
5. A digital signature or EVC verification

The acknowledgement number from Form 10-IEA must then be quoted in ITR-3 (or ITR-4 if she is on presumptive). Forget to quote it and the CPC will treat the regime selection as defective.

The lifetime trap in numbers

Suppose Priya files Form 10-IEA for AY 2026-27 to opt out (old regime). In FY 2027-28 her freelance income jumps to Rs 25 lakh and she realises the 25 per cent surcharge cap inside the new regime now beats her old-regime liability by Rs 80,000. She files Form 10-IEA again to withdraw the opt-out and re-enter the new regime. That second filing is her once-in-a-lifetime allowance.

In FY 2030-31 she takes a sabbatical and earns mostly from house property and dividends; her business income is a token Rs 1.2 lakh from one design retainer. Even though the old regime would now be more favourable, she cannot file Form 10-IEA again. She is locked into the new regime so long as any business or professional income exists. The only escape is a full year with zero business or professional receipts, after which the lock-in resets in the next year that business income reappears.

Use the new regime tax calculator to model both years side by side before triggering the second 10-IEA filing - the form is irreversible in spirit, even if technically you may file it twice.

FAQ

Is Form 10-IE still valid for FY 2025-26?

No. Form 10-IE was the opt-in form used between AY 2021-22 and AY 2023-24, when the old regime was default. The CBDT omitted Form 10-IE and inserted Form 10-IEA via Notification No. 43/2023 dated 21 June 2023 with effect from AY 2024-25. The e-filing portal no longer accepts Form 10-IE submissions. If you have business income and want the old regime for FY 2025-26, file Form 10-IEA only.

What if I forget to file Form 10-IEA before 31 July 2026?

The option to opt out is treated as never exercised. The CPC processes your ITR-3/ITR-4 under the new regime. Filing a belated return under Section 139(4) cannot revive the regime choice for business income earners - the second proviso to Section 115BAC(6) ties the option strictly to the Section 139(1) due date. You will pay tax under the new regime for that year and may file Form 10-IEA the next year if you still wish to opt out.

Can I revise Form 10-IEA if I change my mind?

The form itself is not formally revisable, but the CBDT clarified that filing a revised return under Section 139(5) before the time limit allows you to alter the regime if the original return itself contained an error - provided Form 10-IEA was filed within the original Section 139(1) deadline. If the form was never filed, no revised return can manufacture the option.

Does my employer's TDS regime selection bind me at filing?

No. The employer deducts TDS each month based on the regime you declared in Form 12BB or its internal HR portal. At return filing you may switch to the other regime irrespective of the TDS basis. Excess TDS becomes a refund; short TDS becomes self-assessment tax with interest under Section 234B/234C. See our note on the defective return notice procedure if a regime mismatch triggers a Section 139(9) defect.

I have only capital gains and FD interest. Do I need Form 10-IEA to choose old regime?

No. Capital gains, interest income, dividends, house property, and other sources are not business or professional income. You select the regime inside ITR-2 each year without any separate form. You retain unlimited switching.

What happens if I have salary plus a small Section 44AD trading account?

Any business income, however small, drags you into the Form 10-IEA regime and the lifetime lock-in. There is no de minimis threshold. Even a presumptive intra-day trading account taxed under Section 44AD is enough to trigger the rule. Either keep your trading inside the new regime, or recognise that the old-regime opt-out is a one-shot decision that compounds over decades.

Is the once-in-a-lifetime switch really lifetime?

The statute uses the phrase 'only once in his life time'. CBDT FAQs published on incometax.gov.in confirm the strict reading. The only practical reset is a year with zero business or professional income, after which a fresh Form 10-IEA may be filed when business income resumes. Plan accordingly: see also Section 80C in FY 2025-26 and Section 80CCD(1B) NPS rules before deciding which regime gives you the deduction firepower you actually intend to use over the next ten years.