India MSME 45-Day Payment Rule: Section 43B(h) Explained

The India MSME 45-day payment rule is not really one rule. It is a timing framework under the MSMED Act that changes based on supplier status and contract terms. If the supplier is a Udyam-registered micro or small enterprise, the buyer generally must pay within 15 days when there is no written agreement, or by the agreed due date when there is one, subject to an outer cap of 45 days.

If the payment crosses that statutory deadline, the consequence is not limited to supplier friction. The buyer can face monthly compound interest at three times the RBI bank rate, and Section 43B(h) can defer the income-tax deduction until the year the payment is actually made. That is why this issue belongs in accounts payable controls, not only in a tax memo or vendor dispute file.

The practical questions are straightforward:

• Is the supplier actually covered as a micro or small enterprise for this purpose?
• Is there a written agreement, and what does it say?
• When did acceptance or deemed acceptance happen?
• What is the real statutory due date?
• If payment is delayed, is this now a tax, interest, disclosure, or escalation issue?

Once you answer those questions consistently at the invoice level, the rule becomes manageable. If you do not, the same invoice can create a payment delay problem, a tax deduction problem, and a year-end review problem all at once.

Which Suppliers Are Actually Covered, and Which Are Not

The first control is not date calculation. It is supplier classification. Section 43B(h) is tied to amounts payable to a micro or small enterprise beyond the timeline allowed under Section 15 of the MSMED Act. That means buyers should not treat every supplier that uses the word "MSME" in the same way.

In practice, the cleanest evidence point is the supplier's Udyam Registration Number plus the current classification shown on the Udyam record or certificate. If the supplier is classified as micro or small, the statutory payment timeline becomes relevant. If the supplier is medium, the buyer should not assume the same delayed-payment and tax treatment applies. That distinction matters because year-end flags built too broadly create noise, while flags built too narrowly create real compliance exposure.

The trader issue needs separate handling. The government allows wholesale and retail traders to obtain Udyam registration for priority sector lending purposes, but that does not mean every trader registration should automatically be treated as full Chapter V delayed-payment protection. Where the supplier is a trader, or the business model is mixed, buyers should capture the registration details, understand what the enterprise actually does, and get advice on edge cases rather than relying on a label in the vendor master.

For audit-ready compliance, collect more than a screenshot. A strong file usually includes:

• The supplier's Udyam Registration Number
• The current Udyam certificate or portal verification
• The legal name matching the vendor record and invoice
• A supplier declaration confirming the enterprise is claiming micro or small status for payment-rule purposes
• The date the supplier first asserted MSME status, especially if the assertion came after onboarding

This is where Udyam registration invoice requirements become practical rather than theoretical. AP teams need a repeatable rule for what evidence must sit behind the supplier record before invoices are marked as covered. If that evidence is missing, the right response is not to guess. It is to pause, verify, and document the outcome.

How Acceptance, Deemed Acceptance, and the Appointed Day Set the Clock

Most errors happen because teams use the invoice date as the answer. The Act is more specific than that. The payment clock turns on acceptance, deemed acceptance, and the appointed day, so AP needs a date trail that reflects what happened in the real workflow.

At a practical level:

• Acceptance is the day the buyer accepts the goods or services.
• Deemed acceptance applies when no written objection is raised within 15 days of delivery or service.
• The appointed day is the day immediately after 15 days have passed from acceptance or deemed acceptance, and it becomes the statutory reference point when there is no written agreement.

That matters because a written agreement does not give unlimited flexibility. If there is no written agreement, payment should be made within 15 days. If there is a written agreement, the buyer can follow the agreed date only up to the legal ceiling of 45 days from acceptance or deemed acceptance. A contract that says 60 or 90 days does not displace that outer limit for a covered supplier.

The operational challenge is that acceptance is rarely one clean moment. Goods may be delivered before the invoice is processed. Services may be completed before the approver signs off. A dispute may be raised, resolved, and then accepted later. That is why AP should capture at least six timestamps: delivery or service completion, invoice receipt, objection date if any, dispute resolution date if any, acceptance or deemed acceptance date, and actual payment date.

If your workflow does not already connect those dates, you need tighter invoice matching controls for acceptance dates, approvals, and payment release. Without that evidence, it becomes difficult to support the statutory due date, especially where a buyer is relying on a dispute or delayed approval to explain why the payment clock started later.

The phrase deemed acceptance MSME payments often sounds abstract in tax summaries. In AP operations, it simply means that silence has consequences. If no written objection is raised within the permitted window, the buyer may lose the ability to argue that the clock never started.

What Missing the Deadline Changes for Tax, Interest, and Disclosures

Once a covered invoice crosses the statutory deadline, the issue moves beyond vendor aging. Section 43B(h) tax disallowance means the buyer generally gets the deduction only in the year the payment is actually made. Missing the MSMED Act deadline removes the usual comfort that payment before the tax return filing date might otherwise provide under other Section 43B timings. For businesses with a large March creditor balance, that can turn a payment-timing lapse into a taxable-income issue very quickly.

The interest side is separate and should stay separate in your analysis. Under Section 16, late payment can attract monthly compound interest at three times the RBI bank rate. That is not ordinary commercial interest and it is not usually something you can bargain down by pointing to standard payment terms in the purchase order. When teams search for MSME payment penalty interest, this is the rate structure they are usually trying to understand.

There is another layer that finance teams often miss: interest payable under the MSMED framework is generally not deductible for income-tax purposes. So the economic cost is worse than the rate alone suggests. You can end up with delayed principal deduction under Section 43B(h), non-deductible interest, and a supplier dispute running at the same time.

Year-end readiness matters as well. Amounts due to micro and small enterprises, along with related interest exposure, can feed financial-statement disclosure requirements. If the business only starts reviewing supplier MSME status during tax provision or statutory audit season, the analysis usually becomes slower, more manual, and less reliable than it should be.

The practical takeaway is to keep three buckets separate in your close process:

1. Principal still unpaid past the statutory deadline
2. Interest exposure created by the delay
3. Disclosure items that may need to be reported

When those buckets are merged into one generic "MSME issue" label, errors follow. When they are tracked separately, the buyer can decide what must be paid immediately, what must be disallowed, and what must be disclosed.

When Samadhaan, MSEFC, or TReDS Make Sense

Not every delayed payment ends in litigation, but buyers should understand the routes available once ordinary follow-up fails. The MSME SAMADHAAN portal is the government's delayed-payment filing platform for micro and small enterprises. Cases can move into the Micro and Small Enterprise Facilitation Council process, which is why record quality matters long before a formal claim is filed.

From the buyer's perspective, this is not just a supplier-relations issue. If a case reaches the Facilitation Council, the quality of your acceptance records, dispute notices, payment trail, and supplier-status evidence becomes central. A weak file can make a timing argument look improvised even when the business believes it had a legitimate objection.

TReDS solves a different problem. It is a trade receivable discounting mechanism that helps with financing accepted receivables. In other words, TReDS is about liquidity against an accepted invoice, while Samadhaan and the Facilitation Council are about delayed-payment redress. They can sit in the same ecosystem of MSME receivables, but they should not be treated as substitutes for each other.

The scale of delayed-payment disputes shows why finance teams should not dismiss this as a fringe issue. According to the Ministry of MSME's 2024-25 annual report on delayed-payment cases, micro and small enterprises had filed 216,221 delayed-payment applications involving Rs 47,677.28 crore through 15 December 2024 since the launch of the portal.

That scale changes the compliance posture for both sides. Suppliers need to know when the statutory route is worth using. Buyers need to know when a delayed invoice is no longer just a collections conversation and has become a documented MSME claim risk.

An AP Control Checklist to Avoid Section 43B(h) Surprises

The most reliable way to manage the rule is to turn it into a checklist that starts before the invoice reaches the payment run.

• Flag potentially covered suppliers at onboarding. Do not wait for year-end. Collect Udyam evidence, verify the legal entity, and decide whether the supplier should be tracked as potentially covered.
• Store contract terms with the supplier record. If there is a written agreement, AP should be able to see the agreed payment term immediately and know that the legal ceiling still stops at 45 days for a covered supplier.
• Capture acceptance evidence alongside invoice data. Delivery proof, service confirmation, dispute notices, and approval timestamps should sit in the same audit trail as the invoice.
• Calculate a statutory due date, not just a commercial due date. If both dates are relevant, keep both fields and report on the earlier statutory risk.
• Refresh supplier evidence periodically. A one-time onboarding check is not enough if supplier status, entity details, or document quality change over time.
• Escalate before close. Review unpaid covered balances before tax provisioning, return filing, and financial-statement signoff so Section 43B(h), interest exposure, and disclosures are not discovered too late.
• Retain proof of payment. Bank value date, payment reference, and ledger mapping should be easy to produce if the timing is challenged later.

For many teams, this checklist works best when it is connected to adjacent invoice controls. Data created in India's GST e-invoicing, IRN, and IRP workflow can help establish invoice identity and processing consistency, while India's e-way bill rules when invoice data feeds goods movement compliance can support the delivery and movement evidence that often matters when acceptance timing is disputed.

If you are building policy from scratch, start with three controls first: supplier-status verification, acceptance-date capture, and a statutory due-date report reviewed before payment and again before year-end. Those three controls solve most of the avoidable errors that make the MSME payment rule expensive.