CORAA
University · Form 3CD Clause 21(b)

Section 40(a) TDS disallowance Calculator.

Estimate the gross expense disallowance where TDS was not deducted or was not deposited by the return-filing due date. Use this as a review queue, not as an automatic legal conclusion.

Potentially defaulted expenses
Clause 21(b) triage result
Resident gross exposure @ 30%₹1,50,000
Non-resident gross exposure @ 100%₹0
Gross potential disallowance₹1,50,000
Less: evidenced relief entered₹0
Estimated residual for review₹1,50,000
The output is a gross exposure estimate. Review payee residence, applicability, deduction/deposit dates, return-filing due date, payee-side evidence and the second proviso before finalising the tax computation.

Link the disallowance back to the payment.

The calculator is intentionally coarse. The actual working paper should carry one row per payment, payee type, TDS section, amount, deduction date, deposit date, return-filing due date, correction status and Clause 34 reference. This tool gives the manager a number to reconcile—not a number to paste blindly.

Open the working paperReconcile TDS first

How to use this triage calculator

Enter the resident-payee and non-resident-payee expense populations separately. Resident exposure is modelled at 30% and non-resident exposure at 100% where a default is selected.

Enter an evidenced relief amount only after the payment-wise review supports it. The tool does not decide payee-side cure, Section 201 relief or the year in which the expense becomes allowable.

Export the result, then complete the row-level working paper and tie the final conclusion to Clause 21(b), Clause 34 and the tax computation.

Common mistakes

Applying 30% to every TDS mismatch
A rate mismatch, timing difference or already-cured item may not be the same as a non-deduction or late-deposit exposure. Reconcile each payment.
Combining resident and non-resident payments
The resident and non-resident limbs have different rates, evidence and reporting implications. Keep them separate in Clause 21(b).
Ignoring Clause 34
Clause 21(b) tax disallowance and Clause 34 TDS particulars answer different questions. Cross-reference both working papers.

Frequently asked questions

What is the resident Section 40(a)(ia) disallowance rate?+
The commonly applied disallowance is 30% of the sum payable to a resident where the relevant TDS default is not cured under the applicable provisions. Verify the facts and year-specific law before finalising.
What is the non-resident Section 40(a)(i) disallowance rate?+
The non-resident limb is generally modelled at 100% of the relevant sum where the TDS default applies. This calculator is a gross triage estimate and does not replace payment-wise testing.
Is the disallowance permanent?+
It is generally a timing disallowance where the statutory cure conditions are met, but the year of allowance and payee-side relief require evidence and professional review.
Related calculators
Section 40(a) working paperTDS reconciliation checkerClause 34 guide
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Last reviewed: 2026-09-15 · For informational purposes only — not professional advice.