Section 43B(h) of the Income-tax Act, 1961 denies you a deduction for any amount payable to a micro or small enterprise that is still unpaid on 31 March, where the payment has crossed the deadline fixed by Section 15 of the MSMED Act, 2006. That deadline is 15 days without a written agreement and a maximum of 45 days with one. The expense does not vanish, but it moves to the year of actual payment, and your taxable income for the current year rises by the full amount.

For a business running a 60-day or 90-day payment cycle, Section 43B(h) converts an ordinary working capital practice into a tax cost. A manufacturer carrying ₹80 lakh of overdue micro and small enterprise payables on 31 March adds that entire sum back to income and funds roughly ₹24 lakh of extra tax at a 30% effective rate, months before recovering the deduction. The checklist below sets out what to track, when to track it, and where the numbers must eventually reconcile.

01What Is Section 43B(h) and Why Does It Disallow MSME Vendor Payments?

It is a payment-linked deduction rule inserted by the Finance Act 2023 with effect from AY 2024-25. Where an expense is payable to a micro or small enterprise and is not settled within the MSMED Act timeline, the deduction is deferred to the year in which the money actually moves.

Section 43B(h) carries one feature that separates it from every other clause of Section 43B. For statutory dues such as PF, GST or bonus, the proviso to Section 43B allows the deduction if payment is made before the due date for filing the return. That rescue is not available here. The MSMED deadline is the only deadline that counts, which means a March invoice paid in July cannot be saved by an early return filing. Businesses that treat this as a year-end adjustment discover the problem during income tax audit, by which time nothing can be done about it.

02Who Does Section 43B(h) Apply To, and Which Vendors Are Covered?

It applies to every buyer claiming a deduction on the accrual basis, and it covers only suppliers that are micro or small enterprises registered under the MSMED Act. Medium enterprises fall outside the provision entirely.

Three filters decide whether a given vendor is inside the net:

The trader exclusion is the single most common source of error, and it is not visible from the Udyam number alone. You have to read the activity recorded on the certificate. If your vendor onboarding process captures Udyam details at all, this is the field to add. Our MSME registration services team sees the reverse problem just as often: a genuine small manufacturer that has never registered and therefore falls outside a protection meant for it.

03What Are the 15-Day and 45-Day Deadlines Under Section 15 of the MSMED Act?

Section 15 gives you 15 days from the day of acceptance or deemed acceptance where there is no written agreement, and whatever period the written agreement specifies, subject to an absolute ceiling of 45 days. The clock starts on acceptance, not on the invoice date.

That distinction does real work. Deemed acceptance occurs when the buyer raises no written objection within 15 days of delivery of goods or rendering of services. If your team inspects material and records a rejection or quality dispute in writing, the acceptance date shifts and the deadline shifts with it. If nobody writes anything down, deemed acceptance applies and you have lost the argument before it starts.

A written agreement is worth having, because it buys 30 extra days over the default. What it cannot do is buy more than 45. Where a contract specifies 60 or 90 days, the excess has no effect, and professional opinion is genuinely divided on what happens next. One view is that the period is simply capped at 45 days. The other is that the offending clause is void, throwing the transaction back to the 15-day default. Choose a position, apply it to every vendor consistently, and record the reasoning in the audit file rather than deciding invoice by invoice.

04How Do You Build a Section 43B(h) Compliance Checklist?

Build it around the vendor master rather than the ledger, because the question is always about who the supplier is before it is about what is owed. The seven steps below form a working Section 43B(h) compliance checklist for a business of any size, and they align with what your tax auditor will ask for.

• 1 Flag MSME status in the vendor master. Add three fields to every vendor record: Udyam registration number, enterprise category, and activity type. Collect a copy of the Udyam certificate at onboarding and refresh the declaration annually, since a vendor can cross the threshold from small to medium and drop out of the provision.
• 2 Verify the activity, not just the number. Open each certificate and read whether the vendor is recorded as a manufacturer, a service provider or a trader. Traders sit outside Section 43B(h) on the prevailing view. Save the certificate against the vendor record so the position is defensible two years later when the file is reopened.
• 3 Capture the acceptance date on every inward document. Configure your goods receipt note or service acceptance record to carry a date, and make written rejection the documented exception. This one field determines the deadline for every invoice from a covered vendor, and reconstructing it after the year end is close to impossible.
• 4 Put written agreements in place, capped at 45 days. Issue a short standard payment clause to every micro and small enterprise vendor specifying a credit period within the ceiling. Without an agreement the default is 15 days, which almost no accounts payable cycle can meet reliably.
• 5 Run a monthly MSME payables ageing report. Age the covered balances by acceptance date, not invoice date, with buckets at 15, 30 and 45 days. Monthly is the minimum useful frequency; quarterly leaves too little time to act. Businesses without the internal bandwidth for this often fold it into an outsourced bookkeeping arrangement so the report arrives without being chased.
• 6 Do a March sweep before the year closes. In the first week of March, extract every covered balance that will still be outstanding on the 31st and settle what you can. Every rupee cleared before year end stays deductible. This single exercise saves more tax than anything else on this list.
• 7 Reconcile to Form 3CD and MSME Form 1. The closing figures feed two separate filings with two separate regulators. Tie the ageing report to clause 22 of the tax audit report and, if you are a company, to the half-yearly MSME Form 1 filed with the Ministry of Corporate Affairs under Section 405 of the Companies Act, 2013, due on 31 October and 30 April.

Where the accounts payable process is weak rather than the reporting, the fix belongs upstream. An internal audit review of the procure-to-pay cycle usually finds the same three gaps: no acceptance date, no vendor declarations, and no ageing report anyone reads.

05How Is the Disallowance Calculated and What Does It Actually Cost?

You add back the gross amount outstanding on 31 March in respect of covered vendors whose statutory deadline has passed, and claim it as a deduction in the year the payment is made. Section 43B(h) offers no proportionate relief and no threshold below which it can be ignored.

Take a company with a written 45-day agreement that accepts goods worth ₹40 lakh from a small enterprise on 20 February 2026. The deadline falls on 6 April 2026. Because the amount is unpaid on 31 March 2026, the deduction is denied for FY 2025-26 even though the deadline had not yet expired at year end. The safer working assumption is that anything accepted after mid-February and unpaid at year end is exposed.

06How Do You Report MSME Payments in Form 3CD Clause 22?

Clause 22 is where the entire MSME disclosure now sits. The Income-tax (Eighth Amendment) Rules, 2025 substituted it with effect from 1 April 2025, and the amended clause 26 is expressly confined to clauses (a) to (g) of Section 43B.

This catches out anyone working from a pre-2025 checklist, because the old clause 22 asked a single question about interest inadmissible under Section 23. The substituted clause asks three:

The figures reported here must agree with the add-back in the computation of income and with the disclosure of MSME dues in the notes to accounts required by Section 22 of the MSMED Act. Three documents, one number. Where a business is also filing business tax filing returns for group entities, the same vendor may sit in more than one ledger, and the reconciliation has to hold across all of them.

07How Did India's MSME Payment Protection Law Develop?

Before liberalisation there was no statutory remedy for delayed payment to small suppliers at all. Policy protected small-scale industry through reservation of products and licensing restrictions rather than through payment discipline, so a small unit facing a large buyer had contract law and nothing else.

The first real change arrived shortly after 1991 with the Interest on Delayed Payments to Small Scale and Ancillary Industrial Undertakings Act, 1993, which created a statutory right to interest on overdue amounts and was strengthened by amendment in 1998. The MSMED Act, 2006 replaced it with the framework still in force, introducing the micro, small and medium classification, the payment timelines in Section 15, the compound interest in Section 16, the disclosure requirement in Section 22 and the interest disallowance in Section 23, along with the Micro and Small Enterprises Facilitation Councils. The Ministry of MSME maintains the current framework at msme.gov.in.

Two structural shifts since then made enforcement practical. The Companies Act, 2013 gave the Ministry of Corporate Affairs the power used in 2019 to mandate the half-yearly MSME Form 1 return, and the GST Act, 2017 created an invoice-level digital trail that made supplier and buyer records comparable for the first time. Registration moved from Udyog Aadhaar to the Udyam system on 1 July 2020. Businesses still completing that step can do so through Udyam registration support.

Section 43B(h) is the culmination of that arc. For the first time, delayed payment to a small supplier costs the buyer money automatically — through its own tax return, with no action required from the supplier. The revised classification thresholds effective 1 April 2025 and the substituted Form 3CD clause 22 have since tightened the reporting around it. The Income-tax Act, 2025 carries the same rule forward from FY 2026-27 under renumbered provisions, so the compliance discipline built now will not go to waste.

For businesses that would rather have this monitored monthly than rediscovered each March, ongoing accounting and tax compliance support puts the ageing report, the vendor declarations and the year-end sweep on a fixed calendar.

08Frequently Asked Questions on Section 43B(h)

09The Bottom Line

Section 43B(h) is not a year-end problem — it is a year-round process. The tax consequence crystallises on 31 March, but the inputs that drive it are the acceptance date on every goods receipt note, the activity field on every Udyam certificate, and the ageing report that nobody runs until it is too late to act on it. Get those three things right through the year, and the March sweep, the Form 3CD disclosure, and the MSME Form 1 all become outputs of a process rather than a scramble that the audit then takes apart.