New Tax Regime Is Default: How to Opt for Old Regime in AY 2026-27

For AY 2026-27, compare old and new regimes before filing. Learn when old-regime deductions, HRA, home loan interest, and business rules need review.

This guide is written for Indian taxpayers filing FY 2025-26 income in AY 2026-27. It takes an evidence-first approach because most filing errors do not start on the final submit screen — they start earlier, when the taxpayer picks the wrong assessment year, accepts an incomplete prefill at face value, conflates AIS with Form 26AS, or lands on ITR-1 when a different form is required.

Read this as a pre-filing review note. It does not promise a specific refund, faster processing, or notice avoidance. The goal is to help you arrange your facts correctly, choose the right route, and recognise when a CA review is the sensible call.

Key points

Official position to keep in mind

The law requires taxpayers to compute tax under the eligible regime and make sure the return reflects that choice. Taxpayers with business or professional income face additional regime-switching rules — the window for reverting to the old regime is narrower than it is for salaried individuals.

The Income Tax Department's portal, notified forms, and validation rules are the authoritative source for the final filing position. What other websites say about a topic is useful for understanding what taxpayers are searching, but it cannot substitute for matching the return to the taxpayer's own documents.

Practical example

A salaried taxpayer with HRA, Section 80C investments, health insurance under Section 80D, and an outstanding home loan may find the old regime genuinely competitive. A consultant with professional income should separately verify whether Form 10-IEA requirements or business-income restrictions apply before opting out of the new regime.

Work through the example in three passes. First, confirm the assessment year and the correct taxpayer profile. Second, identify the income head, ITR form, and relevant schedule. Third, cross-check tax credits and supporting documents. If any pass produces a mismatch, pause — that is where notices, refund delays, and defective-return problems usually begin.

Documents and evidence to keep ready

• Form 16
• HRA and rent proof
• 80C and 80D proofs
• Home loan certificate
• AIS and Form 26AS

Collect these in one folder along with a short computation note. Even a brief note — "this number appears in the return because of this document" — saves significant time when a Form 16 figure, AIS entry, broker statement, bank interest amount, or tax challan needs to be explained later.

Filing checklist

• Confirm the correct assessment year: AY 2026-27 for FY 2025-26 income.
• Match the article topic to the correct income head and return form.
• Compare Form 16 or Form 16A with AIS, TIS, Form 26AS, bank records, and broker or business records where relevant.
• Keep a note for every mismatch, correction, deduction, refund, or notice-sensitive position.
• File only once the figures are supportable, then e-verify on time.

Mistakes to avoid

• Assuming that the default regime is automatically the best option.
• Claiming old-regime deductions while filing under the new regime.
• Overlooking the business-income regime-switching rules.
• Filing without preserving the supporting proofs.

The most costly mistake is often choosing the wrong remedy after filing. A revised return, a rectification request, AIS feedback, an updated return under ITR-U, a demand payment, a grievance, and a notice reply each solve a different problem. Do not pick a path simply because it is the most visible option on the portal — match the route to what the document and the statute actually allow.

Useful MyeCA paths

• New vs old regime salary guide
• Can salaried switch regime
• Regime comparator
• Choose your ITR form
• Income tax calculator
• Start CA-assisted filing

Use calculators and tools as a preparation layer, not as a substitute for document verification. If the return involves capital gains, foreign assets, business income, a large refund, a tax-credit mismatch, or a notice, review the full position before submitting.

For broader context, keep the complete AY 2026-27 filing guide and the AY 2026-27 form-selection guide open while reviewing the file. For a CA-assisted next step, use expert consultation.

Frequently asked questions

Should I compare regimes every year?

Yes, because income, deductions, and eligibility can change year to year. A regime that worked well last year may not be optimal this year.

Is old regime always worse now?

No. It can still help where eligible deductions and exemptions are large enough to outweigh the benefit of the new regime's lower slab rates.

Should I get CA review before filing?

Use CA review when the facts are not routine, when there is refund or notice risk, or when the return includes capital gains, trading income, foreign assets, business income, regime changes, or AIS/TDS mismatches.

CA technical review note

For this topic, the reviewer should document the selected assessment year, taxpayer status, ITR form, income head, tax regime, source records, and the reason each significant figure appears in the return. Where the position depends on timing — Form 16 issue date, AIS update status, TDS return processing, e-verification, revised-return deadline, or notice response window — record the relevant date alongside the decision.

The minimum file should include the computation, portal downloads, source statements, challans, acknowledgement, and correspondence. This article should not be applied to a specific taxpayer without checking that individual's own documents.

Final takeaway

The new regime being the default does not mean the comparison step can be skipped. The old regime remains relevant where deduction evidence is substantial. Business taxpayers face additional switching rules that need careful verification. Treat regime selection as one element of a complete AY 2026-27 filing file. A clean return comes from consistent treatment across the return, supporting records, tax credits, schedules, declarations, and verification — not from any single decision made in isolation.