Income‑tax Act 2025 & Income‑tax Rules 2026, What Indian Businesses Must Do Now

The Income‑tax Act, 2025 came into force on 1 April 2026, replacing the six‑decade‑old Income‑tax Act, 1961 and introducing a streamlined statutory framework that every Indian business must now navigate. Alongside it, the Central Board of Direct Taxes (CBDT) notified the Income‑tax Rules, 2026 in a series of notifications issued between March and May 2026, overhauling procedural requirements for returns, withholding, transfer pricing documentation and dispute resolution. For CFOs, tax directors, in‑house counsel and chartered accountants, the new income tax rules India demands immediate action: preserving transitional records, revisiting transfer‑pricing policies, updating payroll withholding and mapping every open assessment to the correct statutory pathway.

This guide provides a litigation‑focused, step‑by‑step compliance roadmap designed to help corporates avoid costly missteps during the transition window and defend positions if disputes arise under the new regime.

What Changed, Legal Overview of the Income‑tax Act, 2025 and New Income Tax Rules India

The Income‑tax Act, 2025 represents the most significant structural reform of Indian direct‑tax legislation since independence. Parliament enacted the statute in late 2025, and the government appointed 1 April 2026 as the date on which the charge to income tax would be governed entirely by the new Act. The CBDT subsequently published the Income‑tax Rules, 2026 through a phased notification process, initial core rules in March 2026, supplementary procedural and transfer‑pricing rules in April, and remaining clarificatory notifications through May 2026.

Charge, Definitions and Key Structural Changes

The Act consolidates and simplifies the charging provisions. Industry observers note that the most significant drafting change is the replacement of the legacy “assessment year / previous year” construct with a unified “tax year” concept, reducing confusion in cross‑border and multi‑jurisdictional filings. Definitions of “income,” “person,” and “residence” have been redrafted for clarity, and the Act introduces consolidated schedules for rates, deductions and exemptions previously scattered across multiple chapters and Finance Act amendments.

The procedural architecture has also been reorganised. Return‑filing, assessment, reassessment and appeal provisions are now grouped in sequential chapters, and the income tax rules 2026 prescribe new form numbers, electronic‑filing protocols and timelines that replace their 1962‑era predecessors. Savings clauses within the Act preserve the validity of actions taken under the old regime, but the transitional provisions are complex and require careful mapping, a point explored in the litigation section below.

Timeline of Key Notifications

Corporates should download every notification from the CBDT Rules and Notifications portal and maintain an internal tracker cross‑referencing each new rule to its predecessor under the 1962 Rules. Early indications suggest that the transition will generate a significant volume of clarificatory circulars over the coming quarters.

Key Compliance Actions for Tax Year 2026, Immediate Checklist Under Income Tax Rules India

The compliance window is narrow. Tax teams that delay action risk missed deadlines, incorrect withholding and avoidable penalty exposure. The following checklist, organised by priority, provides an actionable framework for the first 90 days of the new regime.

1. Returns and Filing Deadlines

• Map new form numbers. The Income‑tax Rules, 2026 prescribe entirely new return forms. Identify the correct form for each entity in the group, company, LLP, trust, non‑resident branch, and confirm that your tax‑preparation software has been updated.
• Confirm due dates. Filing deadlines under the new Act may differ from legacy dates. Diarise every deadline against the tax year 2026–27 calendar and build in a two‑week internal buffer for review and sign‑off.
• Verify digital signature certificates (DSCs). Electronic‑filing protocols under the new rules may require updated DSC registrations or fresh authorisation for signing officers.

2. Withholding, Payroll and TDS/TCS Adjustments

• Update payroll systems immediately. Tax slabs and withholding tables under the Finance Act 2026 apply from 1 April 2026. Payroll teams must ensure April salary runs use the correct rates to avoid under‑ or over‑deduction. Salaried employees should be notified of any changes to their net pay.
• Review TDS/TCS rate tables. Cross‑check every applicable TDS and TCS provision against the consolidated schedule in the new Act. Sections have been renumbered, and legacy section references (e.g., the old Section 194 series) are no longer valid for payments made after 1 April 2026.
• Obtain fresh Form 15G/15H declarations. Existing declarations referencing the old Act’s section numbers may need to be refreshed under the new statutory framework.

3. Transfer Pricing Documentation

• Review TP policies and intercompany agreements. Revised documentation rules under the Income‑tax Rules, 2026 introduce updated thresholds and master‑file requirements aligned with OECD/BEPS standards. Ensure that all documentation refers to the correct new rule numbers.
• Initiate contemporaneous documentation early. Do not wait until the filing deadline to begin preparing TP documentation for TY 2026–27. Start gathering data, benchmarking and drafting local files within the first quarter.

4. Corporate Advance Tax Payment Schedule

• Confirm instalment dates. Advance tax instalments for TY 2026–27 follow the new Act’s payment schedule. Verify quarterly dates and compute estimated tax liability under the updated rate structure to avoid interest under the equivalent of the old Section 234C.

5. Record Retention and Evidence Preservation

• Preserve all legacy records. Even though the new Act applies going forward, assessments, appeals and reassessments for prior years will be concluded under savings clauses referencing the old regime. Maintain complete records for at least the statutory retention period under the old Act (typically six to ten years from the relevant assessment year).
• Designate an internal compliance owner. Assign clear responsibility, typically the Tax Director or Head of Finance, for managing the transition. This individual should coordinate across payroll, legal, TP and external advisers.

This compliance checklist income tax 2026 should be treated as a living document and updated each time the CBDT issues new notifications or clarificatory circulars.

Transfer Pricing, Cross‑Border and PE Implications Under the New Income Tax Rules India

Multinational companies operating in India face a particularly complex transition. The revised transfer‑pricing provisions in the Income‑tax Rules, 2026 recalibrate documentation requirements, adjust thresholds and tighten timelines, all while India’s ongoing alignment with OECD BEPS recommendations continues to reshape the international‑tax landscape.

What Multinationals Must Review Immediately

The impact on corporates’ transfer pricing obligations is substantial. Industry observers expect the revised rules to increase documentation burdens for mid‑cap MNCs that previously fell below the old thresholds, while simultaneously introducing more granular master‑file and country‑by‑country reporting requirements consistent with OECD guidance. Key areas requiring immediate attention include:

• Intercompany agreements. Agreements referencing old‑Act section numbers should be amended to cite the corresponding provisions under the Income‑tax Act, 2025. Failure to do so could create documentary gaps during a TP audit.
• Arm’s‑length pricing policies. Benchmark studies prepared under the old regime should be refreshed for TY 2026–27, using the methodologies and comparability standards prescribed by the new rules.
• Permanent establishment (PE) exposure. The new Act’s definition of PE and the attribution rules for income earned through an Indian PE have been redrafted. Non‑resident companies should reassess their Indian presence against the updated definitions.

30/60/90‑Day Action Plan for TP Compliance

Example Scenario: Inbound Royalty Arrangement

Consider a European parent licensing technology to its Indian subsidiary. Under the old Act, the royalty withholding rate and TP documentation referenced specific legacy sections. Under the new income tax rules India 2026, both the withholding provision and the TP documentation rule have been renumbered. If the Indian subsidiary continues to apply the old rates or fails to update its TP documentation, it faces potential disallowance of the royalty deduction and a penalty for non‑compliant documentation, a scenario that is likely to arise with increasing frequency during the transitional period.

Notices, Assessments and Litigation Risks, Transitional Provisions for Tax Litigation India

The transition from the old Act to the new regime is not seamless. Open assessments, pending reassessments and ongoing appeals for prior years must be resolved under the savings clauses of the Income‑tax Act, 2025, while new assessments for TY 2026–27 onward will be governed entirely by the new Act and rules. This dual‑track system creates significant litigation risk, and significant opportunity for well‑prepared taxpayers to strengthen their positions.

Common Transitional Notices and Defence Strategies

The likely practical effect of the transition will be a wave of notices as the tax department adjusts its systems and procedures. Taxpayers can expect:

• Notices referencing incorrect statutory provisions. During the early months, notices may cite old‑Act sections for matters that should be governed by the new Act, or vice versa. Such errors can form the basis for a jurisdictional challenge.
• Reassessment notices for prior years. The savings clauses permit the department to continue reassessment proceedings for years governed by the old Act, but the procedural timelines for issuing such notices must comply with the old Act’s limitation provisions. Taxpayers should scrutinise every notice for time‑bar compliance.
• TP adjustment notices under revised rules. Where TP documentation has been prepared under the old format but relates to a year now subject to the new rules’ documentation requirements, disputes about the adequacy of documentation are virtually certain.

Sample Timeline: Assessment → Appeal → Tribunal → High Court

When to Negotiate vs Litigate

Not every dispute merits full‑scale litigation. The practical calculus depends on the quantum at stake, the strength of the legal position and the precedent value. Industry observers expect the following general principles to apply during the transitional period:

• Negotiate when the dispute involves factual interpretation of transitional provisions, the amounts are modest relative to compliance costs, and the department’s position is administratively reasonable even if technically debatable.
• Litigate when the department has applied the wrong statutory provision (a jurisdictional defect), the amounts are significant, or the issue has precedent value for future years under the new Act. Transitional cases that clarify the scope of savings clauses will carry enormous precedent weight.
• Consider protective filings. Where the law is genuinely uncertain, filing protective appeals within limitation preserves rights while negotiations continue.

A robust litigation risk mitigation checklist should include: (a) immediate time‑bar analysis for every open year, (b) evidence‑preservation protocols for digital and paper records, (c) internal escalation triggers for disputes above a defined monetary threshold, and (d) pre‑authorised budgets for external counsel engagement.

Finance Act 2026 Changes That Matter to Corporates

While the Income‑tax Act, 2025 provides the structural framework, the Finance Act 2026, enacted alongside the Union Budget, governs the annual rate schedule and introduces targeted amendments. Tax directors should focus on the following areas:

• Corporate tax rates. Early indications suggest that the effective corporate tax rate structure (including surcharge and cess) has been rationalised under the new Act’s consolidated rate schedule. However, specific incentive regimes and concessional rates may have been recast, requiring fresh computation.
• Surcharge adjustments. The Finance Act 2026 changes to surcharge thresholds and rates should be modelled against projected taxable income to determine the effective rate for each entity in the group.
• Anti‑avoidance provisions. Specific anti‑avoidance rules (SAAR) have been redrafted and consolidated in the new Act. Corporates with complex structuring should review whether existing arrangements trigger new SAAR provisions.

Payroll and Withholding Nuances for Salaried Employees

The Finance Act 2026’s revisions to individual tax slabs directly affect employer withholding obligations. Payroll teams should recalculate TDS on salary for every employee, update Form 16 generation processes and communicate any net‑pay changes to employees. Where employees have opted for a specific tax regime, payroll systems must correctly apply the corresponding slab under the new statutory framework.

Practical Examples and Short Case Studies, Litigation‑Led Insights

The following anonymised scenarios illustrate common transitional pitfalls and the litigation tactics available to corporates.

Scenario 1: TP Adjustment Notice With Incorrect Statutory Reference

An Indian subsidiary received a TP adjustment notice citing a provision of the old Income‑tax Act for a transaction completed in TY 2026–27. Because the new Act governs all income for TY 2026–27, the notice was jurisdictionally defective. The recommended action was to file a detailed objection before the Dispute Resolution Panel, preserving the jurisdictional challenge while simultaneously addressing the merits. This twin‑track approach protects the taxpayer regardless of how the jurisdictional issue is decided.

Scenario 2: Withholding Shortfall Due to Delayed Payroll Update

A mid‑cap IT company failed to update its payroll system before the April salary run, applying old TDS rates. The shortfall was identified during the first quarterly TDS return. Immediate rectification, paying the shortfall with interest and filing a revised return, limited the exposure to interest charges. The key lesson: proactive payroll system testing before the April cycle would have prevented the issue entirely.

Scenario 3: Reassessment Notice for a Prior Year, Time‑Bar Challenge

A manufacturing company received a reassessment notice in May 2026 for AY 2020–21, referencing the savings clauses of the new Act. Careful analysis revealed that the notice had been issued beyond the time limit prescribed by the old Act’s reassessment provisions, provisions that, under the savings clauses, continued to govern limitation for prior years. The company filed a writ petition before the High Court challenging the notice as time‑barred, relying on established precedent that limitation provisions are procedural safeguards not extinguishable by transitional savings.

Comparison: Old Regime vs New Regime Under Income Tax Rules India

Next Steps, Internal Owner Checklist and External Counsel Triggers

Effective transition management requires clear ownership. The following allocation ensures nothing falls through the cracks:

• CFO / Tax Director: overall accountability for transition; sign‑off on updated return forms; approve advance tax estimates; authorise external counsel engagement for disputes above the defined threshold.
• Head of Payroll / HR: update withholding tables before each salary cycle; issue employee communications; refresh Form 15G/15H collection.
• Legal / In‑house Counsel: review all open assessments and map each to the correct statutory pathway (old Act + savings clause, or new Act); conduct time‑bar analysis; escalate litigation triggers.
• External Counsel: engage immediately for (a) any notice with a potential jurisdictional defect, (b) TP disputes above a material threshold, (c) reassessment notices for prior years, and (d) any matter requiring High Court or Supreme Court intervention.

Tax teams should schedule a formal 90‑day review meeting to assess progress against this checklist and address any CBDT notifications issued after initial implementation.

Conclusion

The simultaneous commencement of the Income‑tax Act, 2025 and the Income‑tax Rules, 2026 represents the most consequential overhaul of income tax rules India has seen in decades. The compliance window is short, the transitional provisions are complex, and the litigation exposure for corporates that delay action is real and escalating. Every Indian business, from listed conglomerates to mid‑cap subsidiaries of foreign multinationals, should treat the first 90 days as a critical implementation period. Preserve records, update systems, map open disputes to the correct statutory pathway, and engage experienced tax litigation counsel where the stakes justify it. The Global Law Experts network connects businesses with specialist practitioners across India and internationally.

For those navigating regulatory changes beyond tax, our coverage of developments such as the RBI new banking rules 2026 and compliance frameworks in other jurisdictions, including Vietnam business visa requirements, provides the practical, cross‑border guidance that modern businesses demand. Visit our lawyer directory to find a specialist or learn more about Global Law Experts.

Sources

1. Income Tax Department (CBDT), All Rules / Notifications
2. Income Tax Department, Income‑tax Rules Page
3. PwC, India Tax Summaries
4. ClearTax, Income Tax Practical Summaries
5. KPMG, Tax Insights and Alerts
6. OECD, Tax and Transfer Pricing Guidance