Short answer. The old regime only wins if your deductions clear a break-even number. For tax year 2026-27, an ₹18 lakh salary pays ₹1,50,800 in the new regime, and the old regime needs about ₹6.42 lakh of deductions to match it. If your only income is salary up to ₹12.75 lakh, the new regime takes no tax at all.
The calculator
Tax & rulesType your numbers for the year. The maths runs on this page and nothing is sent anywhere. Not sure where to start? Load an example and change one thing at a time.
Our calculation, from the rules listed below. Salary minus the standard deduction (₹75,000 new, ₹50,000 old), plus other income, minus the deductions each regime allows, then the slabs, the rebate and the 4% cess. Your Form 16 and the Income Tax Department's own calculator are the final word.
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How to read the break-even
The methodMost of us compare the two regimes the wrong way round. We list our deductions and feel rich. The new regime doesn't care about your deductions. It hands everyone lower slab rates, a ₹75,000 standard deduction and a rebate that wipes out the tax up to ₹12 lakh of taxable income. The old regime's only weapon is deductions. So there's exactly one question: are yours big enough?
The break-even answers it. Take an ₹18 lakh salary with nothing else. The new regime costs ₹1,50,800. To match that, the old regime needs about ₹6.42 lakh of deductions. Now count what you can actually stack without rent or a home loan: 80C ₹1.5 lakh, your own NPS ₹50,000, and health insurance somewhere between ₹25,000 and ₹1 lakh. That's ₹3 lakh at the very most. Short by miles.
That's why the break-even beats any "which regime is better" listicle. It turns a vague feeling into a gap in rupees. If your gap is small, rent you really pay (HRA) or a home loan can close it. If your gap is lakhs wide, the arithmetic has already voted. The vote, though, is yours.
Worked examples
Tax year 2026-27| Salaried, under 60 | New regime | Old regime |
|---|---|---|
| ₹12.75 lakh salary, no deductions | ₹0 | ₹1,87,200 |
| ₹12.85 lakh salary: ₹10,000 over the rebate line, so marginal relief caps the tax at the excess | ₹10,400 | ₹1,90,320 |
| ₹18 lakh salary, HRA exemption ₹2 lakh, 80C ₹1.5 lakh, own NPS ₹50,000, 80D ₹25,000 | ₹1,50,800 | ₹2,18,400 |
| ₹18 lakh salary: deductions the old regime needs to match the new one | about ₹6.42 lakh | |
Illustrative, our calculation, including the 4% cess. Tax rounded to the rupee.
Get the sheet
FreeOld vs new tax regime sheet
Questions people ask
Tax year 2026-27Which tax regime is better for a ₹10, 15 or 20 lakh salary?
With salary as your only income, under 60, for tax year 2026-27: at ₹10 lakh the new regime takes ₹0, and the old regime needs ₹4.5 lakh of deductions just to tie at zero. At ₹15 lakh the new regime costs ₹97,500 and the old regime needs about ₹5.44 lakh of deductions to match. At ₹20 lakh it's ₹1,92,400 against about ₹7.08 lakh. Our calculation, with 4% cess.
What is the break-even in the old vs new regime?
It's the total of old-regime-only deductions (HRA exemption, 80C, 80CCD(1B), 80D, home-loan interest and the rest) at which both regimes cost you the same. Below it, the new regime costs less. Above it, the old one does. The calculator on this page works out yours.
Can I switch between the old and new regime every year?
If you have no business or professional income, yes: the Income Tax Department says you can switch every year, directly in your return, and the old regime has to be chosen before the return's due date. With business income you get only one switch back to the new regime after opting out. Source: Income Tax Department, New vs Old Tax Regime FAQs (FAQ 11).
Is the new tax regime the default?
Yes. The new regime has been the default since AY 2024-25. If you don't choose the old regime, your tax is worked out under the new one. Source: Income Tax Department, New vs Old Tax Regime FAQs (FAQ 12).
Does the ₹12 lakh rebate cover capital gains?
No. Income taxed at special rates, such as certain capital gains, is left out when the rebate is worked out. This calculator handles income taxed at your slab rate only. Source: Income Tax Department, Brief on Budget (section 87A).
The rules this uses
Last verified 21 Oct 2026Every figure in the calculator comes from these official pages. We re-check them every quarter and on Budget day, and log any change on our corrections page.
| Figure | Official source |
|---|
Known limits
Read these first- Resident individuals only, for tax year 2026-27 (April 2026 to March 2027).
- Income taxed at slab rates only. Capital gains and other special-rate income are left out, and they don't count towards the rebate either.
- No surcharge. Above ₹50 lakh of taxable income the totals understate your tax, and the tool tells you so.
- You enter your HRA exemption; the tool doesn't work it out. The HRA rule moved into the new Income-tax Rules, 2026 this year, and we'll add an HRA helper once it's checked against the notified text.
- 80D limits depend on ages in your family. Type the amount you're eligible to claim.
- Family pension, agricultural income, losses carried forward and business income aren't modelled.
Tested against 17 hand-worked cases (v1.0, 21 October 2026), matched to the rupee.
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