Old vs New Regime Simulator
The ultimate battleground for FY 2026-27 (Budget 2025). Input your income and deductions, and let our engine mathematically prove which tax regime destroys less of your wealth.
Old Regime Deduction Engines
Standard Deduction (₹75k New / ₹50k Old) is injected automatically into the engine constraints.
New Regime
Switching absolutely saves you ₹89,700 in dead taxes this fiscal year.
Tax to Govt
₹97,500
Effective Rate
6.5%
Tax to Govt
₹1,87,200
Effective Rate
12.5%
Load Bearing Graph
How is this calculated?
The Government algorithm creates a mathematical spread between two radically different tax systems.
- Strips away all 50+ 80C/HRA/LTA deductions.
- Lowers slab rates structurally.
- Injects ₹12 Lakh Section 87A rebate.
- Flat ₹75,000 Standard Deduction.
- Allows heavy compounding of 80C/HRA/24b deductions.
- Punishes with ancient, high 30% slab rates faster.
- Forces compliance and paperwork submission.
- Flat ₹50,000 Standard Deduction.
Related Calculators
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Book Free ConsultationOld vs New Tax Regime — Complete Budget 2025 Decision Guide
The choice between Old and New Tax Regime is the single most impactful financial decision every Indian taxpayer makes each year. Budget 2025 made the New Regime even more attractive with ₹12L zero-tax income via Section 87A and ₹75K standard deduction. But if you have heavy deductions (home loan, HRA, 80C), the Old Regime can still save you lakhs.
Tax Slab Comparison — Budget 2025
| ₹0 — ₹4,00,000 | NIL |
| ₹4,00,001 — ₹8,00,000 | 5% |
| ₹8,00,001 — ₹12,00,000 | 10% |
| ₹12,00,001 — ₹16,00,000 | 15% |
| ₹16,00,001 — ₹20,00,000 | 20% |
| ₹20,00,001 — ₹24,00,000 | 25% |
| Above ₹24,00,000 | 30% |
| ₹0 — ₹2,50,000 | NIL |
| ₹2,50,001 — ₹5,00,000 | 5% |
| ₹5,00,001 — ₹10,00,000 | 20% |
| Above ₹10,00,000 | 30% |
Deduction Checklist — What Works Where?
The Deduction Threshold Matrix
* Thresholds are approximations and include standard deductions under Budget 2025 structures.
Real-World Decision Scenarios
Fresh Graduate (₹8L CTC, No Investments)
→ New RegimeGross Income: ₹8,00,000
With ₹75K standard deduction, taxable income = ₹7.25L in New Regime. Under ₹12L → Section 87A rebate → ₹0 tax. Old Regime: even with max 80C (₹1.5L), tax would be ~₹15,600. New Regime wins by default.
Mid-Level Manager (₹18L CTC, Renting in Mumbai)
→ Old Regime (if HRA > ₹2L)Gross Income: ₹18,00,000
With 80C (₹1.5L) + 80D (₹25K) + HRA (₹2.4L, Mumbai metro) + Standard Deduction (₹50K) = ₹4.65L deductions. Old Regime taxable: ₹13.35L → Tax ~₹2L. New Regime taxable: ₹17.25L → Tax ~₹2.34L. Old Regime saves ₹34K.
Senior Manager (₹30L CTC, Home Loan + NPS)
→ Old Regime (strongly)Gross Income: ₹30,00,000
80C (₹1.5L) + 80D (₹50K parents senior) + Home Loan Sec24b (₹2L) + HRA (₹3L) + NPS 80CCD(1B) (₹50K) + SD (₹50K) = ₹7.5L deductions! Taxable: ₹22.5L → Tax ~₹4.37L. New Regime: ₹29.25L → Tax ~₹5.85L. Old Regime saves ₹1.48L!
Freelancer (₹40L, No HRA, No Home Loan)
→ New RegimeGross Income: ₹40,00,000
No HRA (self-employed), no home loan. Only 80C (₹1.5L) + 80D (₹25K) + NPS (₹50K) = ₹2.25L deductions. Not enough to overcome New Regime's lower slab rates. New Regime tax ~₹8.58L. Old Regime ~₹9.36L. New Regime saves ₹78K. Plus, switching back is a one-time lifetime option for business income.
Quick Decision Framework
Income ≤ ₹12.75L?
→ New Regime (₹0 tax via 87A)
No Home Loan + No HRA?
→ New Regime (can't accumulate enough deductions)
Total Deductions > ₹3.75L?
→ Run this simulator — Old Regime likely wins
Home Loan + Metro HRA + 80C maxed?
→ Old Regime almost certainly wins
Freelancer (Sec 44ADA)?
→ Choose carefully — Old Regime lock-in is permanent
Legal Framework & Compliance
Section 115BAC: The New Tax Regime is governed by Section 115BAC of the Income Tax Act. It became the default regime from FY 2024-25. Opting for Old Regime requires explicit communication to employer or selection during ITR filing.
Business Income Lock-in: If you have business/professional income and choose Old Regime, you can switch to New Regime only once. After switching back to New, you cannot return to Old. For salaried employees without business income, no such restriction exists.
Disclaimer: Tax slabs and deduction limits follow the Finance Act 2025 (Budget 2025). Section 87A rebate applicability and surcharge rates may change with future amendments. Always verify current rates on incometax.gov.in before making regime decisions.
Frequently Asked Questions
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