Section 40(a)(ia) of the Income Tax Act, 1961 is one of the most consequential TDS compliance provisions for businesses — failing to deduct or deposit TDS on time disallows 30% of the payment as a business expense. Under the Income Tax Act, 2025 (effective from Tax Year 2026-27), this provision continues in equivalent form. This guide covers the exact rules, the 30% disallowance mechanics, the Form 26A relief mechanism, the new Act's equivalent sections, and a practical decision framework for businesses to avoid disallowances in FY 2026-27.
Section 40(a)(ia) creates a direct financial penalty for TDS non-compliance in business expenses. When a business pays amounts that are subject to TDS under Chapter XVII-B (salary, contractor fees, rent, professional charges, interest, etc.) and either:
Then 30% of the amount paid/credited is disallowed as a business expense deduction. This disallowance applies even though the payment was genuinely made for business purposes. The tax impact is direct: disallowed expense → higher taxable income → higher tax.
| Parameter | Rule |
|---|---|
| Disallowance percentage | 30% of the expense (reduced from 100% by Finance Act 2014, effective AY 2015-16) |
| When it applies | TDS not deducted; OR TDS deducted but not deposited before ITR due date under Section 139(1) |
| Who it applies to | All businesses and professions computing income under "Profits and Gains of Business or Profession" — companies, LLPs, firms, individuals, HUFs with business income |
| Exemption | Does NOT apply to 44AD, 44ADA, 44AE presumptive taxpayers (no expense-wise computation) |
| When disallowance reverses | In the year TDS is actually deducted and deposited — allowed as deduction in that year |
| Relief mechanism | Form 26A — payee's CA certifies payee has paid tax on the income; payer not treated as assessee-in-default |
| Payments to non-residents | Section 40(a)(i) — stricter: 100% disallowance if TDS not deducted on payments to non-residents |
| New Act 2025 equivalent | Section 43(1)(b) — same mechanics, updated section number |
| Provision | Old Act 1961 | New Act 2025 | Change? |
|---|---|---|---|
| TDS disallowance on resident payments (30%) | Section 40(a)(ia) | Section 43(1)(b) | Same mechanics; section renumbered |
| TDS disallowance on non-resident payments (100%) | Section 40(a)(i) | Section 43(1)(a) | Same mechanics; section renumbered |
| Cash payment disallowance (₹10K limit) | Section 40A(3) | Section 43(2) | Same limit; section renumbered |
| Excessive payments to relatives disallowance | Section 40A(2) | Section 43(3) | Same; section renumbered |
| Payment certainties (bonus, PF, statutory dues) | Section 43B | Section 37 | Same; MSME 45-day rule continues as Section 37(2)(g) |
| Form 26A relief mechanism | Second proviso to Section 40(a)(ia) | Equivalent second proviso to Section 43(1)(b) | Unchanged in substance |
TechCo Pvt. Ltd. pays ₹15,00,000 to a digital marketing consultant in FY 2025-26 without deducting TDS under Section 194J (old Act). The consultant's invoice is ₹15L + ₹1.5L GST.
MicroFab LLP pays ₹8,00,000 to contractors in FY 2025-26 (March 2026). TDS of ₹1,60,000 (2%) deducted but deposited only on 20 August 2026 — after the July 31 ITR due date for AY 2026-27.
Sunrise Software Pvt. Ltd. (turnover ₹8 crore) engaged 12 freelancers and 3 agencies totalling ₹30,00,000 in professional fees during FY 2025-26. Their CFO noticed in March 2026 that TDS under Section 194J had not been deducted on 3 agency payments totalling ₹9,00,000 made in October 2025.
Even if you missed TDS on a payment to a resident, Section 40(a)(ia)'s second proviso saves you if all four conditions are met:
A Chartered Accountant certifies these facts in Form 26A and uploads it on TRACES (tdscpc.gov.in). Once uploaded, the payer is not treated as assessee-in-default and Section 40(a)(ia) disallowance does not apply.
Preventing Section 40(a)(ia) / Section 43(1)(b) disallowances requires systematic process controls:
Tag every vendor in your ERP with the applicable TDS section, rate, and threshold. When a payment is processed, the system automatically computes TDS. No manual calculation means no missed deductions.
Before the 7th of every month, reconcile all vendor payments in the previous month against TDS deducted and challan deposits. Any outstanding TDS should be deposited without fail. March TDS (special rule) should be deposited by 30 April.
Before filing ITR (especially for tax audit companies — ITR due 31 October), run a complete "TDS vs payments" reconciliation. Identify any payments where TDS was missed or deposited late. Deposit outstanding TDS before ITR filing date to prevent the disallowance from crystallising.
The Tax Audit Report (old Form 3CD, new Form 26 under new Act) requires your auditor to report all instances of TDS disallowance under Section 40(a)(ia). Ensure your accounts payable team provides accurate TDS data to the auditor, and that any genuine missed TDS is either paid before the audit report date or Form 26A is arranged.