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Old vs new regime tax

Old vs new regime tax: calculation method, required inputs, worked check, limitations and a link to Income Tax Calculator India. Reviewed 25 September 2026.

By Uddhav Gopani, FounderPublished 25 September 2026Reviewed 25 September 2026

Old regime vs new regime is a rates-versus-deductions trade. For FY 2025-26 the old regime runs 0% to ₹2.5 lakh, 5% to ₹5 lakh, 20% to ₹10 lakh and 30% above, with deductions subtracted first. The new regime runs eight gentler slabs from ₹4 lakh to a 30% band above ₹24 lakh, with nearly all deductions removed.

What this specific question is asking

Side by side: the new regime adds a ₹75,000 salary standard deduction and a full 87A rebate up to ₹12 lakh of taxable income; the old regime keeps ₹50,000 standard deduction, an 87A ceiling of ₹5 lakh, and every chapter VI-A deduction. Which one wins depends entirely on how much you can subtract under the old rules.

Compare totals, not marginal rates: compute full tax under both regimes including cess, then compare the payable figures. A lower slab rate somewhere in the middle of the table tells you nothing until the deduction base is accounted for.

Inputs to verify

Verify income type before calculation; if this value uses a different unit, period or definition, convert or restate it first.
Verify gross annual income (₹) before calculation; if this value uses a different unit, period or definition, convert or restate it first.
Verify tax regime before calculation; if this value uses a different unit, period or definition, convert or restate it first.
Verify deductions, old regime (₹) before calculation; if this value uses a different unit, period or definition, convert or restate it first.

Step-by-step check

Enter your gross annual income.
Choose the New regime or the Old regime.
If you picked Old, enter your total eligible deductions (the New regime ignores them).
Tap Calculate for the tax, the 4 percent cess, and your effective rate.

Worked example and sanity check

As a worked reference for “Old vs new regime tax”, Worked example FY 2025-26, AY 2026-27 · old regime · income type: salary / eligible pension. On ₹7,00,000 gross salary the salary standard deduction of ₹50,000 applies (it does not apply to freelance / business / other income); assuming no other eligible deductions, taxable income is ₹6,50,000. Under the old-regime slabs (nil to ₹2,50,000; 5% on ₹2,50,001–5,00,000; 20% above ₹5,00,000): ₹12,500 + 20% × ₹1,50,000 = ₹42,500 , plus 4% health & education cess = ₹44,200. This calculator adds the 4% cess and applies the new-regime simplified rebate-threshold marginal relief just above ₹12,00,000, but does not calculate surcharge or other high-income marginal relief . These are FY 2025-26 / AY 2026-27 figures, not timeless “current rates.” Compare the resulting magnitude with a second set of inputs; if those disagree materially, inspect the setup before trusting the decimal precision.

Interpreting the result

The output is only useful against a reference. The example's ₹6,50,000 gives that reference: your own result should be explainable against it — larger or smaller for a reason you can name. Read the magnitude before the decimals: a result ten times too large or small almost always means a unit or period slipped, not that the formula failed.

Reviewed 25 September 2026

Verify any current tax threshold, lender rate, provider rule or health guidance with the authoritative source before acting.

Use the Income Tax Calculator India

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Authoritative references

Income Tax Department of India

Common questions

Which inputs matter most for old vs new regime tax?

The key inputs are Income type, Gross annual income (Rs), Tax regime, Deductions (old regime only, Rs). Match their units and periods before using Income Tax Calculator (India).

How can I check an answer for old vs new regime tax?

Run the example exactly as written, then vary income type alone. A result that tracks that change predictably tells you the setup — units, periods, definitions — is correct.

When should I recalculate old vs new regime tax?

Recalculate whenever any input's basis changes: a new measurement, a revised rate or threshold, a different period convention, or an updated policy figure.