New Tax Regime vs Old Tax Regime — Break-Even Analysis and Statutory Crossover Points for Tax Year 2026-27

Statutory Framework — Income Tax Act, 2025

The new regime operates under Section 115BAC (consolidated within the Act's default provisions). The old regime's deductions are governed by Schedule XV read with Section 123 (formerly 80C), Section 124 (formerly 80D), Section 125 (formerly 80CCD(2)), and Section 10(13A) (HRA — unchanged in section number).

Critical procedural change from April 1, 2026: Employees must submit Form 124 (replacing Form 12BB) at the start of each Tax Year to declare regime preference and investment declarations. Failure to submit Form 124 defaults to the new regime. Under the Income Tax Act, 2025, a salaried employee who does not file ITR by July 31, 2026 loses the right to opt for the old regime for Tax Year 2026-27.

Tax Slabs — New Regime, Tax Year 2026-27

Standard Deduction: ₹75,000. Section 87A Rebate: Full tax waived up to ₹12,00,000 net income (effective gross salary: ₹12,75,000 for salaried). Plus 4% Health and Education Cess on all computations.

Tax Slabs — Old Regime, Tax Year 2026-27

Standard Deduction: ₹50,000. Section 87A Rebate: Up to ₹5,00,000 net income. 4% Cess applies.

Break-Even Deduction Analysis

The break-even deduction is the total deduction value at which old regime tax equals new regime tax. If actual deductions exceed the break-even amount, the old regime is more favourable. All figures pre-cess.

Key Deductions: Availability by Regime

Employer NPS under Section 125 is the critical exception — it survives the new regime at an enhanced limit of 14% of basic salary (up from 10% under Section 80CCD(2) of the old Act). For employees in the new regime, this is the primary tax-saving instrument.

Employer Compliance — Form 124 Obligations

1. Collect Form 124 from every employee at the start of Tax Year 2026-27
2. Default to new regime for employees who do not submit Form 124
3. Old regime employees must provide investment proofs including HRA workings, home loan interest certificate (Form 16A from lender), and 80C investment statements
4. Issue Form 16 using new Act section references (Section 392(1) for TDS; Section 123 for 80C-equivalent deductions)
5. Employees who switch regime at ITR stage: excess TDS is refunded; shortfall must be paid before July 31, 2026

HRA City Expansion — Now 8 Metros

The Finance Act 2025 expanded the 50% HRA exemption to 8 cities from April 1, 2026:

Bengaluru, Hyderabad, Pune and Ahmedabad employees previously entitled to 40% HRA now qualify for 50% under the old regime — this increases the old regime's attractiveness for these cities by approximately ₹18,000–₹36,000 in annual tax saving depending on salary level.

The Practical Decision Rule

Add up all deductions you can genuinely claim: HRA + home loan interest + 80C + 80D + NPS 80CCD(1B). Compare to the break-even figure from the table above.

• If actual deductions exceed break-even — opt for old regime via Form 124
• If not — default to new regime (or simply don't submit Form 124)
• If gross salary is ₹12,75,000 or below — new regime produces zero tax; old regime cannot outperform zero