Most people think their entire salary gets taxed at one rate. That is not how it works — and understanding the difference can save serious money.
India uses a slab-based progressive tax system. Different portions of income are taxed at different rates. Only the income that falls within a particular slab is taxed at that slab’s rate — not everything.
How Tax Slabs Actually Work
Think of it like filling buckets. Each bucket has a size (income range) and a rate (tax %). You fill the first bucket before moving to the next.
On a ₹15 lakh income under the new regime:
| Slab | Amount in Slab | Rate | Tax |
|---|---|---|---|
| ₹0 – ₹4L | ₹4,00,000 | 0% | ₹0 |
| ₹4L – ₹8L | ₹4,00,000 | 5% | ₹20,000 |
| ₹8L – ₹12L | ₹4,00,000 | 10% | ₹40,000 |
| ₹12L – ₹15L | ₹3,00,000 | 15% | ₹45,000 |
| Total Tax | ₹1,05,000 |
The effective tax rate is just 7% — not 15%, which is the rate on the top slab. This is the most common misconception about taxes.
The Two Regimes: New vs Old
From FY 2025-26, there are two tax systems to choose from. The new regime is the default unless you actively opt for the old one while filing.
New Tax Regime (Default)
Simpler slabs, lower rates, but most deductions are not allowed.
| Income | Tax Rate |
|---|---|
| Up to ₹4 lakh | Nil |
| ₹4L – ₹8L | 5% |
| ₹8L – ₹12L | 10% |
| ₹12L – ₹16L | 15% |
| ₹16L – ₹20L | 20% |
| ₹20L – ₹24L | 25% |
| Above ₹24L | 30% |
Key advantages:
- Standard deduction of ₹75,000 for salaried individuals
- Section 87A rebate: zero tax on income up to ₹12 lakh
- For salaried: effectively zero tax up to ₹12.75 lakh (₹12L + ₹75K standard deduction)
- Same slabs for all ages — seniors get no extra exemption here
Old Tax Regime (Optional)
Higher rates but allows deductions under 80C, 80D, HRA, home loan interest, and more.
| Income | Tax Rate |
|---|---|
| Up to ₹2.5 lakh | Nil |
| ₹2.5L – ₹5L | 5% |
| ₹5L – ₹10L | 20% |
| Above ₹10L | 30% |
Senior citizens (60–80 years): Basic exemption ₹3 lakh Super seniors (80+): Basic exemption ₹5 lakh
Key advantages:
- Deductions under 80C (₹1.5L), 80D, HRA, home loan interest available
- Section 87A rebate still applies for income up to ₹5 lakh (old regime)
- Better for those with high eligible deductions
The Section 87A Rebate — The Most Misunderstood Rule
Section 87A is a tax rebate — not a deduction. It directly wipes out tax liability rather than reducing taxable income.
New regime (FY 2025-26):
- If taxable income ≤ ₹12 lakh → entire tax liability is waived (rebate up to ₹60,000)
- If taxable income = ₹12,00,001 → rebate does NOT apply, full tax is payable
- This cliff effect means crossing ₹12 lakh by even ₹1 can trigger ₹60,000+ tax
Old regime:
- Rebate applies if taxable income ≤ ₹5 lakh → tax becomes zero
Important catch: The 87A rebate does not apply to special-rate incomes like capital gains from equity mutual funds or stocks. Even if total income is under ₹12 lakh, capital gains are taxed at their applicable flat rates.
Real Calculations at Common Income Levels
₹8 Lakh Income (Salaried, New Regime)
- Gross salary: ₹8,00,000
- Standard deduction: ₹75,000
- Taxable income: ₹7,25,000
- Tax on ₹7.25L: ₹16,250
- Section 87A rebate applies (income < ₹12L): full rebate
- Tax payable: ₹0
₹15 Lakh Income (Salaried, New Regime)
- Gross salary: ₹15,00,000
- Standard deduction: ₹75,000
- Taxable income: ₹14,25,000
- Tax calculation: ₹0 + ₹20,000 + ₹40,000 + ₹33,750 = ₹93,750
- Add 4% cess: ₹3,750
- Tax payable: ₹97,500
₹15 Lakh Income (Salaried, Old Regime with ₹3L deductions)
- Gross salary: ₹15,00,000
- Deductions (80C ₹1.5L + 80D ₹25K + NPS ₹50K + standard ₹50K): ₹2,75,000
- Taxable income: ₹12,25,000
- Tax: ₹12,500 + ₹1,50,000 + ₹67,500 = ₹2,30,000
- Add 4% cess: ₹9,200
- Tax payable: ₹2,39,200
At ₹15 lakh with ₹2.75L deductions, the new regime saves ₹1,41,700.
New vs Old: When Does Old Regime Win?
The old regime only makes sense when deductions are very high. General break-even points:
| Income Level | Old Regime Wins If Deductions Exceed |
|---|---|
| ₹10 lakh | ~₹2.5 lakh |
| ₹15 lakh | ~₹4.5 lakh |
| ₹20 lakh | ~₹5.5 lakh |
Deductions that count for this calculation include 80C investments (PPF, ELSS, insurance premium), 80D health insurance, NPS under 80CCD(1B), home loan interest under Section 24, and HRA exemption.
For most salaried employees without a home loan or very high insurance commitments, the new regime now wins at most income levels.
Surcharge: The Hidden Tax Above ₹50 Lakh
Beyond the slab rates, a surcharge applies on higher incomes. It is calculated on the tax amount, not income.
| Total Income | Surcharge Rate |
|---|---|
| ₹50L – ₹1 crore | 10% |
| ₹1 crore – ₹2 crore | 15% |
| Above ₹2 crore (new regime) | 25% |
On top of surcharge, a 4% health and education cess applies to everyone on the final tax amount (including surcharge). This is automatically included in all tax calculations.
Cess, TDS, and Advance Tax Explained
Cess: A 4% charge added to the final tax amount. On ₹1,00,000 tax, cess adds ₹4,000. Total = ₹1,04,000. Non-negotiable, applies to everyone.
TDS (Tax Deducted at Source): For salaried employees, the employer deducts tax monthly before crediting salary. The total TDS for the year is reconciled when filing ITR. If TDS exceeds actual liability, a refund is issued. If it falls short, the balance is paid at filing.
Advance Tax: For freelancers, business owners, and those with income beyond salary, taxes must be paid in quarterly instalments during the financial year:
- 15 June: 15% of estimated annual tax
- 15 September: 45% cumulative
- 15 December: 75% cumulative
- 15 March: 100%
Penalty under Section 234B applies if advance tax is underpaid.
Special Tax Rates: What Slabs Don’t Cover
Some income types are taxed at fixed flat rates outside the normal slab structure:
- Short-term capital gains (equity/mutual funds, Section 111A): 20%
- Long-term capital gains (equity/MF above ₹1.25L): 12.5%
- Lottery / game show winnings: 30% flat (no basic exemption)
- Crypto and virtual digital assets: 30% flat + 1% TDS
These are charged on the gains amount directly, not added to regular income for slab calculation.
Choosing Your Regime: A Quick Decision Guide
Go with New Regime if:
- Income is under ₹12 lakh (salaried) — zero tax
- No home loan
- Investments are primarily for wealth building, not tax saving
- Want simpler filing
Consider Old Regime if:
- Paying home loan interest above ₹2 lakh/year
- Claiming HRA in a high-rent city
- Total eligible deductions (80C + 80D + 80CCD + HRA + home loan) exceed ₹4–5 lakh
- Senior citizen with high medical expenses
The easiest approach: calculate tax under both regimes using any income tax calculator online, compare the final figures, and pick the lower one. The option must be declared when filing ITR — it cannot be changed after filing for that year.
Tax for Senior Citizens and NRIs
Senior citizens (60–79 years) under old regime:
- Basic exemption raised to ₹3 lakh (vs ₹2.5L for general)
- Saves ₹2,500 compared to general category
- 80TTB deduction: up to ₹50,000 on FD/savings interest (vs ₹10,000 under 80TTA for others)
- Under the new regime, no age-based exemption benefit applies — same slabs as everyone
Super senior citizens (80+) under old regime:
- Basic exemption ₹5 lakh — significant advantage
- No tax up to ₹5L without needing any investments
- Under new regime, same slabs as all others apply
NRIs:
- Can choose between old and new regimes
- Basic exemption of ₹2.5 lakh in old regime only (no higher limit for NRI seniors)
- NRI income earned outside India is not taxable in India
- Indian-sourced income (rent, dividends, capital gains) is taxable at normal slab rates
- No Section 87A rebate available to NRIs
Common Mistakes to Avoid
- Assuming the top slab rate applies to full income. Only the portion within that slab is taxed at the higher rate.
- Not declaring regime choice at the start of the year. Employers need this early to calculate correct TDS. Changing mid-year is complicated.
- Missing the 87A rebate cliff. Earning ₹12,00,001 instead of ₹11,99,999 can cost ₹60,000+ in tax.
- Ignoring cess in calculations. Always add 4% to any tax estimate — it is mandatory.
- Treating capital gains as regular income. Flat rates apply to these regardless of total income.
The Bottom Line
India’s tax slab system is designed so you only pay higher rates on the income above a threshold — not on your entire earnings. The new regime offers zero tax up to ₹12 lakh (₹12.75 lakh for salaried) and simple slabs topping out at 30% above ₹24 lakh. The old regime still makes sense for high deduction claimants, but for most taxpayers in 2026 the new regime delivers lower tax with less complexity.
Understanding which slab your income falls in — and which regime benefits you more — is the starting point for all effective tax planning.
Disclaimer: Tax rates, rebate limits, and rules are as per FY 2025-26 (AY 2026-27) regulations. Tax laws may change with each Union Budget. Always verify current rates on the Income Tax Department’s official website (incometax.gov.in) or consult a Chartered Accountant before making tax decisions.
