Old vs New Tax Regime AY 2026-27: The Deadline Trap
You're filing your FY 2025-26 return, the portal has already ticked "New Regime" for you, and you're about to hit submit. Stop. For a slice of ₹15L+ earners the old regime still wins — but only if you choose it before 31 July 2026. Miss that date and the choice disappears: a belated return is taxed under the new regime by default, and every rupee of 80C, 80D, HRA and home-loan interest you were banking on is gone.
Here's the decision, with the breakeven math most "which regime" guides skip.
Summary
| Gross salary | Tax — New regime | Tax — Old, zero deductions | Deductions needed for old to win |
|---|---|---|---|
| ₹12.75 lakh | ₹0 (87A rebate) | ₹1,87,200 | New wins outright |
| ₹15 lakh | ₹97,500 | ₹2,57,400 | ₹5.44 lakh |
| ₹20 lakh | ₹1,92,400 | ₹4,13,400 | ₹7.08 lakh |
| ₹25 lakh | ₹3,19,800 | ₹5,69,400 | ₹8.00 lakh |
| ₹50 lakh | ₹10,99,800 | ₹13,49,400 | ₹8.00 lakh |
All figures include 4% cess. New-regime tax is after the ₹75,000 standard deduction; old-regime after ₹50,000. The last column is the total exemptions plus deductions you'd need under the old regime just to match your new-regime tax — claim anything less and new is cheaper.
How the two regimes differ in FY 2025-26
New regime — the default, and now hard to beat
The FY 2025-26 slabs: nil up to ₹4 lakh, 5% to ₹8 lakh, 10% to ₹12 lakh, 15% to ₹16 lakh, 20% to ₹20 lakh, 25% to ₹24 lakh, and 30% above ₹24 lakh. The Section 87A rebate (up to ₹60,000) makes income up to ₹12 lakh tax-free — ₹12.75 lakh for salaried once you add the ₹75,000 standard deduction. The trade-off: you claim almost nothing else. No 80C, no HRA, no 80D.
Action: if your only "deduction" is EPF and you have no home loan, stop here — new regime is your answer.
Old regime — worth it only when deductions are large
The old slabs are steeper: nil to ₹2.5 lakh, 5% to ₹5 lakh, 20% to ₹10 lakh, 30% above ₹10 lakh. Standard deduction is ₹50,000 and the 87A rebate only covers income up to ₹5 lakh. What it buys you is the full deductions menu — 80C (₹1.5 lakh), 80CCD(1B) NPS (₹50,000), 80D health premiums (₹25,000–₹75,000), HRA under Section 10(13A), and home-loan interest under Section 24(b) (₹2 lakh on a self-occupied house).
Action: add up every deduction you can actually claim with proof, then compare it to the breakeven for your income in the table. Below the line, old regime quietly costs you money.
Why the breakeven rises with income
At ₹15 lakh you need ₹5.44 lakh of deductions for old to win; by ₹25 lakh that climbs to ₹8 lakh and flattens there. The reason: the new regime's lower slabs are worth more in absolute rupees as income rises, so you need a bigger deduction pile to overtake it. Most earners without a home loan never clear ₹5 lakh — 80C ₹1.5L + 80D ₹50K + NPS ₹50K is only ₹2.5 lakh of it.
Action: unless you carry a home loan or a large metro HRA, assume new regime until the exact sum proves otherwise.
The one case old regime still wins: metro rent + home loan
A Bengaluru renter on ₹40,000 rent claiming HRA under 10(13A) can shield ₹3–4 lakh on its own; stack ₹1.5 lakh of 80C and ₹50,000 of NPS and a metro tenant can approach the ₹5–8 lakh breakeven. Home-loan borrowers get there fastest — ₹2 lakh of Section 24(b) interest plus a full 80C does most of the work.
Action: if you both rent in a metro and run an active 80C, model both regimes — you may be the exception.
Real example: Salaried, ₹28L, Bengaluru, home loan
Priya owns a flat in Bengaluru and assumed her home loan made the old regime an obvious pick. Her deductions: 80C ₹1.5 lakh, NPS under 80CCD(1B) ₹50,000, 80D ₹75,000, and home-loan interest under Section 24(b) ₹2 lakh — ₹4.75 lakh in all.
| Item | Old regime | New regime |
|---|---|---|
| Taxable income | ₹22.75 lakh | ₹27.25 lakh |
| Deductions used | ₹4.75 lakh | ₹75,000 only |
| Annual tax (incl. cess) | ₹5,14,800 | ₹4,13,400 |
Even with a home loan and a full ₹4.75 lakh of deductions, Priya pays ₹1,01,400 more under the old regime — because at ₹28 lakh her breakeven is ₹8 lakh and she's ₹3.25 lakh short. New regime is the right call. Habit alone would have cost her over a lakh.
The deadline trap most people miss
The new regime is the default for AY 2026-27. As a salaried taxpayer with no business income, you can still switch to the old regime — but only inside a return filed on or before 31 July 2026. File even one day late and Section 115BAC gives you no choice: a belated return is taxed under the new regime, full stop. No 80C, no HRA, no home-loan interest — even if old would have saved you a lakh.
If you have any business or professional income, the bar is higher: you must file Form 10-IEA before the due date to opt for the old regime, and switching back in later years is restricted. (Above ₹50 lakh of taxable income, surcharge applies under both regimes — another reason to run the real numbers, not a thumb-rule.)
Action: if old regime is your answer, file before 31 July — treat the deadline as the decision, not a formality.
The two-tab portal nobody warned you about
The new Income Tax Act, 2025 took effect on 1 April 2026, so the e-filing portal now shows two tabs — one for the Income Tax Act 1961 and one for the Income Tax Act 2025. Your FY 2025-26 return is filed under the old Act: pick the Income Tax Act 1961 / AY 2026-27 tab. The wrong tab files for the wrong year and gets your return treated as defective. While you're in there, reconcile your AIS and Form 26AS before submitting — any income the department can see but you didn't declare is an automatic notice.
What to do this week
- Pull your AIS, TIS and Form 26AS from the portal and total your actual FY 2025-26 deductions, with proof.
- Compare that total to the breakeven for your income in the table above.
- Below breakeven: file under the new regime — it's already the default, nothing extra to do.
- Above breakeven: choose the old regime inside a return filed before 31 July 2026 (Form 10-IEA first if you have business income).
Don't let the calendar pick your regime
At ₹15L+ incomes the regime choice is worth a lakh or more a year — but only if you make it deliberately and on time. Run your real numbers instead of a rule of thumb, and file before the deadline so the decision stays yours, not the portal's default.
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