Deductions only available under the old regime

The old tax regime’s entire appeal comes down to one thing: deductions that reduce taxable income before tax is calculated. But a deduction’s face value and its actual worth in rupees saved are two different numbers, and confusing them is the easiest way to misjudge which regime actually wins.

A deduction is worth your marginal rate, not its face value

A ₹1,00,000 deduction doesn’t save ₹1,00,000 — it saves whatever tax would otherwise have applied to that ₹1,00,000 slice of income. Since India’s slabs are progressive, that rate depends entirely on where in your income that slice sits: a deduction that removes income taxed at 30% saves far more than the same rupee amount removing income taxed at 5%. A single large deduction can even span more than one slab, saving a blended rate rather than one flat percentage.

What ₹5,35,000 of deductions is actually worth

Take someone earning ₹15,00,000 a year, claiming this calculator’s own default combination of old-regime-only deductions: ₹1,50,000 under Section 80C, ₹50,000 additional NPS under 80CCD(1B), ₹2,00,000 home loan interest under 24(b), ₹25,000 health insurance under 80D, ₹10,000 savings interest under 80TTA, and ₹1,00,000 combined other deductions (HRA and similar) — ₹5,35,000 in total, on top of the ₹50,000 standard deduction every old-regime filer gets regardless.

That savings figure is also the entire reason the old regime wins at all here. At the same ₹15,00,000 income, the new regime’s tax (with only its own standard deduction and 80CCD(2)) comes to ₹88,140. With the itemized deductions claimed, the old regime narrowly wins by ₹1,300. Without them, it loses by ₹1,50,540 — a landslide in the new regime’s favour. The deductions aren’t a nice-to-have on top of an already-competitive old regime; for this income level, they’re the only reason it’s competitive at all.

Which deductions only apply under the old regime

The new regime allows just two reductions to taxable income: its own (larger) standard deduction, and Section 80CCD(2), the employer’s NPS contribution. Every other common deduction is old-regime-only: Section 80C (₹1,50,000 cap — PPF, ELSS, life insurance premiums, and similar), Section 80CCD(1B) (₹50,000, your own additional NPS contribution, on top of 80C), Section 24(b) (₹2,00,000, home loan interest on a self-occupied property), Section 80D (₹25,000, or ₹50,000 for senior citizens — health insurance premiums), Section 80TTA/80TTB (₹10,000, or ₹50,000 for senior citizens — savings and deposit interest), Section 80E (uncapped — education loan interest, for up to 8 years), and HRA exemption along with Section 80G donations and similar, bundled as “other deductions.”

None of these need to apply to everyone to matter — someone with no home loan and no HRA to claim might still clear ₹1,50,000 through 80C alone and come out ahead under the old regime, while someone with none of these at all is almost always better off under the new regime’s lower rates. The only way to know which side of that line you fall on is to add up exactly what you can genuinely substantiate, not what you qualify for on paper.