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The Finance Act 2023 inserted Section 43B(h) into the Income-tax Act. Effective AY 2024-25, any amount owed to a Udyam-registered Micro or Small enterprise beyond the MSMED Act Section 15 deadline (15 days no written agreement, 45 days with written agreement) is added back to taxable income at year-end and only allowed as a deduction in the year of actual payment. For a controller at a mid-market SME with 400 vendors and no separate MSME classification in the vendor master, the annual March-25 discovery that Rs 22 lakh of past-45-day MSME AP has crystallised a Rs 5.5 lakh disallowance is what turns a compliance calendar into a working-capital crisis. The failure surface is not the rule itself but the absence of a vendor-master field that captures Udyam registration status, URN issue date, and MSME classification at the invoice level.
Three filters must fire together for the disallowance to apply. Filter 1: MSME classification — the vendor is Micro (investment up to Rs 1 crore AND turnover up to Rs 5 crore) or Small (investment up to Rs 10 crore AND turnover up to Rs 50 crore) under the MoMSME June 2020 threshold notification. Medium enterprises are outside scope. Filter 2: Udyam registration — the vendor holds a valid 19-character URN in the format UDYAM-XX-00-0000000, verifiable on the Udyam public portal. Filter 3: not a trader — the July 2021 MoMSME Office Memorandum excludes wholesale and retail trade enterprises from all MSMED benefits except Priority Sector Lending. If any filter fails, Section 43B(h) does not apply. If all three fire and the invoice is unpaid past the appointed day at March 31, the amount is added back to taxable income, disclosed in Form 3CD Clause 22, and the deduction is deferred to the payment year.
A vendor-master field capturing Udyam registration status, URN, URN issue date, and current classification (Micro, Small, Medium, Trader-only, Non-MSME). Batch verification of URNs against the Udyam public portal at quarterly cadence to catch classification drift. AP ageing report with an MSME filter and an appointed-day column that computes the 15 or 45-day deadline from the invoice acceptance date. A year-end reconciliation pass at March 31 that lists every past-appointed-day MSME payable, quantifies the disallowance at the applicable tax rate (25.17 per cent for Section 115BAA filers), and outputs the Form 3CD Clause 22 disclosure worksheet. A payment prioritisation queue that surfaces MSME invoices approaching the 15 or 45-day deadline for release before the disallowance crystallises.
Every MSME vendor carries a verified URN and classification tag in the master. AP ageing surfaces past-appointed-day MSME payables continuously, not annually. Year-end disallowance is quantified before March 31, and the payment prioritisation run either releases the exposed payables before year-end or provides for the tax charge with a documented reversal expectation. Form 3CD Clause 22 disclosure is populated from the reconciled MSME payables ageing rather than reconstructed at audit time. Section 16 MSMED Act interest at three times bank rate compounded monthly is tracked separately as a non-deductible cost, not surfaced as a surprise at the statutory audit. The tax auditor's evidence base is the reconciled MSME classification register, the year-end ageing, and the disclosure worksheet — not a March-25 scramble against 400 vendor cards.
It is 9:14pm on March 27. Your CA has just emailed. Subject line: “Section 43B(h) — please confirm your MSME payables list by tomorrow”. The email says something about a 45-day rule, Micro and Small enterprises, and a tax disallowance if the year-end payables list is not clean. You have 400 active vendors, no separate MSME classification in the vendor master, and four working days before the financial year closes.
You have heard the term Section 43B(h). You know it is a Finance Act 2023 amendment. You are not entirely sure what triggers the disallowance, which of your 400 vendors it actually applies to, or what the exposure looks like if you do nothing before March 31.
Quick answer. Section 43B(h) says that any amount you owe to a Micro or Small enterprise registered under the MSMED Act 2006 — beyond the payment deadline (15 days without a written agreement, 45 days with one) — is added back to your taxable income at year-end and can only be claimed as a deduction in the year of actual payment. The rule is effective from AY 2024-25 (FY 2023-24 onwards). It applies to buyers, not to traders. Your exposure is checkable in an afternoon if your vendor master already flags Udyam-registered MSME suppliers, and takes a working week if it does not.
What is Section 43B(h) actually?
The Finance Act 2023 inserted clause (h) into Section 43B of the Income-tax Act 1961. Section 43B is the general provision that allows certain expenses — tax, duty, interest, employee contributions — as deductions only on actual payment basis rather than on accrual. Clause (h), added in 2023, extends this treatment to amounts payable to Micro and Small enterprises, but only where the payment exceeds the deadline specified in Section 15 of the MSMED Act 2006.
The consequence is that if you have a Rs 12,00,000 unpaid MSME invoice on your balance sheet at March 31, and that invoice is past the 15 or 45-day deadline, the Rs 12,00,000 gets added back to your taxable income for the year. You get the deduction only in the year you actually pay — which for a March 31 discovery means the deduction shifts to the following financial year, a full-year deferral of the tax outflow.
This is a permanent working-capital penalty until the payment is released. It is not a fine or a penalty in the enforcement sense; it is a tax deferral by way of disallowance, and it hits the current year’s tax charge directly at the concessional rate you file under.
Which of my vendors does the rule apply to?
Three filters have to fire together.
Filter 1 — MSME classification. Only Micro and Small enterprises count. Medium enterprises are explicitly excluded. Under the MoMSME notification of 26 June 2020, the composite investment-and-turnover thresholds are:
- Micro: Investment in plant and machinery or equipment up to Rs 1 crore AND turnover up to Rs 5 crore.
- Small: Investment up to Rs 10 crore AND turnover up to Rs 50 crore.
- Medium: Investment up to Rs 50 crore AND turnover up to Rs 250 crore. Not covered by Section 43B(h).
Filter 2 — Udyam registration. The vendor must be registered on the Udyam portal (udyamregistration.gov.in), which replaced the older Udyog Aadhaar Memorandum system in July 2020. Every registered enterprise carries a 19-character Udyam Registration Number (URN) in the format UDYAM-XX-00-0000000 — the state code, followed by the district code, followed by a seven-digit serial. You verify a URN at the Udyam portal’s public “Verify Udyam Registration Number” page. If the URN does not verify, the vendor is not an MSME under the Act, and Section 43B(h) does not apply.
Filter 3 — Not a trader. The MoMSME Office Memorandum dated 2 July 2021 confirmed that wholesale and retail trade enterprises can register on Udyam only for the limited purpose of Priority Sector Lending benefits under the RBI framework. They are not treated as MSMEs for any other benefit — including the Section 15 protection and, by extension, Section 43B(h) coverage. If your Udyam-registered vendor is a distributor, dealer, or reseller rather than a manufacturer or a service provider, Section 43B(h) does not fire on that payable.
If any one of these three filters fails, Section 43B(h) does not apply to that vendor. If all three fire, the fourth question — how many days the invoice has aged past the appointed day — determines whether the disallowance crystallises this year or next.
How do I check the payment deadline?
Section 15 of the MSMED Act defines the “appointed day” — the day by which the buyer must have paid the supplier.
- No written agreement: 15 days from the date of acceptance (or deemed acceptance) of the goods or services.
- Written agreement in place: whatever the agreement specifies, capped at 45 days from the date of acceptance.
An agreement clause specifying 60 or 90 days is legally void. The enforceable ceiling is 45 days. This means the practical outcome for a written-agreement vendor is 45 days, and for a no-written-agreement vendor is 15 days. The MSME registration date embedded in the URN issue history tells you when the vendor became an MSME — payables raised before that date fall outside the rule, and payables raised after, unpaid past the appointed day, fire the disallowance at year-end.
What happens if I miss it?
Consider a controller at a Rs 200 crore SME manufacturer running 400 active vendors. At year-end on March 31, 60 of the vendors are Udyam-registered Micro or Small enterprises (verified URN, not traders). Of those, Rs 22,00,000 of aggregate accounts payable sits past the 45-day appointed day. Under Section 43B(h), the entire Rs 22,00,000 is added back to taxable income for the year.
At the concessional corporate tax rate of 25.17 per cent under Section 115BAA — the rate most mid-market SMEs file under after cess and surcharge — the additional tax burden is approximately Rs 5,53,740 for the year, or roughly Rs 5.5 lakh. The disallowance reverses in the year of actual payment: if the Rs 22 lakh is cleared in April immediately after year-end, the deduction lands in the following financial year and the tax benefit unwinds in that year’s return. For a March 31 discovery, that is a full-year deferral of a Rs 5.5 lakh cash outflow to the Income Tax Department.
The disclosure has to appear in the Tax Audit Report under Clause 22 of Form 3CD, which the statutory auditor tests during the audit. A missed disclosure surfaces as an audit qualification and — depending on materiality — creates re-assessment exposure under Section 143(3) in a subsequent scrutiny cycle. Separately, Section 16 of the MSMED Act charges compound interest at three times the RBI-notified bank rate on the delayed principal, and that interest is not deductible under Section 37 of the Income-tax Act by virtue of Section 23 of the MSMED Act. The total year-end cost head is the principal disallowance plus the compound interest plus the audit disclosure risk, not any one of these in isolation.
The one thing to check first
Before you tackle the full vendor master reclassification exercise — which takes days — run the fastest exposure check. Pull the AP ageing at March 31, filter to invoices past 45 days, and cross-reference the vendor list against the Udyam public directory. The Udyam portal exposes registered vendors publicly, and a batch verification of your top 100 payables usually reveals within a few hours whether you have a real exposure or a scare.
If the exposure is real, the immediate action is one of two things. Either release the payment before March 31 to eliminate the disallowance for the current year, or accept the disallowance and provide for the tax charge in the current year’s tax provision, then track for the deduction reversal in the year of payment. The MSME 45-day payment compliance tracker guide covers the ongoing operational tracking discipline once the initial exposure is quantified, and the Section 43B(h) MSME payment reconciliation article covers the reconciliation logic that connects vendor master, AP ageing, and payment records into the tax provision worksheet.
The two industry-specific cascade briefs
Two of the sharpest failure patterns show up in ancillary supply chains where a large buyer sources from clusters of small MSME job workers. The Section 43B(h) chemical ancillary vendor 45-day cascade walks through the failure mode in the chemical ancillary sector, where a single delayed payment from an OEM cascades through three tiers of Micro and Small processors and produces a compounding disallowance at every tier. The Section 43B(h) steel ancillary vendor 45-day cascade reconciliation covers the equivalent structural pattern in steel processing, where the disallowance compounds across job-work billing and material-issue cycles that most vendor masters do not model as MSME AP ageing at all.
If your business sits inside either supply chain, the cascade brief for your sector is the depth read — the pattern of how a single missed payment at the top of the chain compounds into a Rs 40-plus lakh disallowance across ancillary tiers is documented with worked numbers rather than restated principles.
When the manual spreadsheet outgrows itself
For a company with fewer than 50 MSME vendors and clean vendor master data, the March 27 email from the CA is manageable — an afternoon of exposure calculation, a payment release run before March 31, and a clean year-end. For a company with 200-plus Udyam-registered vendors across multiple business units and multiple GSTINs, the annual scramble becomes a structural problem. The failure modes compound: URN classification drift as a vendor moves from Micro to Small or from Small to Medium mid-year and the tracker does not update; payment-date-versus-invoice-date reconciliation across bank statements where a March 31 wire posts on April 1 and the appointed-day clock does not stop cleanly; interest calculation under Section 16 MSMED Act at the RBI-notified rate that changes twice a year; and the NACH bounce reversal pattern where an attempted payment reverses and the appointed-day counter restarts with the reversal date rather than the original payment date.
The Section 43B(h) MSME disallowance estimator tool is the fastest way to quantify a specific exposure — plug in the AP ageing buckets and the applicable tax rate and it produces the disallowance figure and the tax charge in seconds. Above the threshold where the annual scramble becomes an operational hazard, Terra Insight’s reconciliation software for India treats the MSME payables ageing as a continuously refreshed queue with the URN classification, the appointed-day calculation, and the Form 3CD Clause 22 disclosure trail as first-class outputs rather than a March-25 reconstruction against 400 vendor cards under time pressure.
Go deeper
- Section 43B(h) MSME payment reconciliation — the reconciliation-layer guide
- MSME 45-day payment compliance tracker — the ongoing operational discipline
- Section 43B(h) chemical ancillary vendor 45-day cascade
- Section 43B(h) steel ancillary vendor 45-day cascade reconciliation
- NACH bounce recovery under Section 43B(h)
- Section 43B(h) MSME disallowance estimator (tool)
- Reconciliation software for India — money page
Frequently Asked Questions
How is Section 43B(h) different from just paying my MSME vendors late?
Paying an MSME vendor late has always triggered a Section 16 MSMED Act interest liability at three times the RBI-notified bank rate compounded monthly, and that interest has always been non-deductible under Section 37 of the Income-tax Act (via Section 23 of the MSMED Act). Section 43B(h) is a separate consequence added by the Finance Act 2023 — from AY 2024-25 onwards, the principal amount of the unpaid invoice itself is added back to your taxable income at year-end and is only allowed as a deduction in the year of actual payment. So late payment now carries three cost heads instead of one: the accrued Section 16 interest, the disallowance of the principal until paid, and the working-capital cost of the tax deferral. A Rs 22 lakh unpaid balance past 45 days at March 31 is a Rs 5.5 lakh tax charge for the current year plus an accrued interest cost that never becomes deductible.
What if my vendor registered on Udyam mid-year — do the old invoices before their registration date count?
No. The MSME protection under Section 15 of the MSMED Act attaches from the date of Udyam registration onward. Invoices raised before the vendor’s URN registration date fall outside the appointed-day framework because the supplier was not, at the invoice date, a registered MSME. Payables raised after the registration date, unpaid past the 15 or 45-day deadline, fire the Section 43B(h) disallowance at year-end. The practical implication is that your vendor master must capture the URN issue date, not just the current URN — a vendor who registered on Udyam in November 2025 does not backdate the protection to invoices raised in June 2025. This is one of the sharpest edges of the annual exposure calculation, because a controller who filters purely on “is this vendor Udyam-registered today” will over-state the disallowance by picking up pre-registration invoices.
How do I actually verify a Udyam Registration Number without asking the vendor?
The Udyam portal (udyamregistration.gov.in) exposes a public verification tool at the “Verify Udyam Registration Number” page. You enter the 19-character URN (format UDYAM-XX-00-0000000, where XX is the state code, 00 is the district code, and 0000000 is the seven-digit serial) and the tool returns the enterprise name, registration date, principal activity code, and current classification (Micro, Small, or Medium). For a batch verification of your top 100 payables, an analyst can process the list in a working day. Where the URN does not verify — because the vendor supplied a URN that never existed, or the URN was cancelled — the vendor falls outside Section 43B(h) coverage but the underlying commercial relationship still carries the credit risk you should investigate. The public verification is the fastest way to separate real MSME exposure from noise, and it does not require any contact with the vendor.
Does the 45-day deadline apply to services or only to goods?
Both. Section 15 of the MSMED Act 2006 applies to any supplier who supplies goods or renders services — the 15-day (no written agreement) and 45-day (with written agreement) deadlines run identically for a Micro or Small enterprise service provider as for a manufacturer. The “date of acceptance” for services is the day the service is deemed completed and accepted by the buyer; for goods it is the date of physical acceptance after inspection. A Small enterprise consultancy raising a Rs 4,80,000 invoice on 1 October with no written agreement must be paid by 16 October (15 days from acceptance) or the buyer’s Section 43B(h) exposure begins from the sixteenth day. The “day of acceptance” interpretation is where most disputes arise — buyers argue for the completion certificate date, suppliers for the invoice date — and the safer position for the buyer is to run the 15 or 45-day clock from the earliest defensible acceptance date rather than the latest.
What if I discover the Section 43B(h) exposure in April after the financial year is already closed?
The disallowance has already crystallised for the closed year — you cannot retrospectively pay the invoice in April and claim the March 31 deduction back. The correct treatment is to include the disallowance in the tax provision for the closed year’s books at the applicable rate (25.17 per cent under Section 115BAA for most mid-market SMEs, 22 per cent for select cases, 30 per cent for companies opting out of the concessional regime), disclose it under Clause 22 of Form 3CD in the Tax Audit Report, and then track the reversal to be claimed in the next year when the payment is actually released. A Rs 22 lakh April discovery becomes a Rs 5.5 lakh tax charge in the current year’s provision and a Rs 5.5 lakh deferred tax asset (assuming payment is expected within the next year), which unwinds when the invoice is settled and the deduction lands in the payment year. The permanent-loss risk sits on cases where the vendor relationship has already broken down and payment is not expected to happen — in which case the disallowance stays on the books indefinitely and never reverses.
Content authored by practitioners with experience at Amazon India, Intuit QuickBooks, and the Tata Group. Meet the team →
- ▸ Section 43B(h), Income-tax Act 1961 (inserted by Finance Act 2023) — Any sum payable by the assessee to a Micro or Small enterprise beyond the time limit specified in Section 15 of the Micro, Small and Medium Enterprises Development Act 2006 shall be allowed as a deduction only in the previous year in which such sum is actually paid, notwithstanding that any expenditure was incurred on the accrual basis in a prior year. The clause is effective from Assessment Year 2024-25 (Financial Year 2023-24 onwards). Where a Micro or Small enterprise vendor invoice sits unpaid past the appointed day at March 31, the corresponding amount is added back to taxable income for the year and the deduction shifts to the year of actual payment — a permanent working-capital deferral until the payment is released and disclosed.
- ▸ Section 15, MSMED Act 2006 — Where any supplier supplies any goods or renders any services to any buyer, the buyer shall make payment therefor on or before the date agreed upon between him and the supplier in writing or, where there is no agreement in this behalf, before the appointed day. Provided that in no case the period agreed upon between the supplier and the buyer in writing shall exceed forty-five days from the day of acceptance or the day of deemed acceptance. The appointed day where no written agreement exists is fifteen days from the day of acceptance of the goods or services. This is the statute that defines the 15-day and 45-day windows the Section 43B(h) disallowance is anchored to — an agreement clause specifying 60 or 90 days is legally void, and the enforceable cap remains 45 days.
- ▸ Section 2, MSMED Act 2006 — MSME classification and MoMSME Notification S.O. 2119(E) dated 26 June 2020 — A Micro enterprise is one where investment in plant and machinery or equipment does not exceed one crore rupees and turnover does not exceed five crore rupees. A Small enterprise is one where investment does not exceed ten crore rupees and turnover does not exceed fifty crore rupees. A Medium enterprise is one where investment does not exceed fifty crore rupees and turnover does not exceed two hundred fifty crore rupees. Section 43B(h) applies only to Micro and Small enterprises — Medium enterprises are explicitly outside the scope of the disallowance regardless of Udyam registration status. The composite investment-and-turnover criteria mean a vendor breaching either limit moves to the next category, and the buyer's MSME classification tracker must refresh at the year-end vendor master reconciliation to catch upward-drift cases where an ancillary supplier has grown past the Small threshold.
- ▸ MoMSME Office Memorandum F.No.5/2(2)/2021-E/P&G/Policy dated 2 July 2021 — Retail and wholesale trade — Retail and wholesale trade enterprises may register on the Udyam portal for the limited purpose of Priority Sector Lending benefits under the RBI framework. Such enterprises shall not be considered as MSMEs for any other benefits under the MSMED Act 2006 or the schemes framed thereunder. The consequence for Section 43B(h) is that a Udyam-registered distributor, dealer, or reseller vendor does not fall within the Micro or Small enterprise definition for the disallowance regime — the buyer's classification filter must exclude such traders even where the URN verifies on the portal. Verify the vendor's principal activity code against the Udyam registration record before applying the disallowance.
- ▸ Rule 6G and Clause 22 of Form 3CD, Income-tax Rules 1962 — Every assessee liable to audit under Section 44AB shall furnish the audit report in Form 3CB and the statement of particulars in Form 3CD. Clause 22 requires disclosure of the amount of interest inadmissible under Section 23 of the MSMED Act 2006 and, following the Finance Act 2023 amendment, the disclosure has been extended to capture the amounts inadmissible under Section 43B(h) of the Income-tax Act. The tax auditor tests the Section 43B(h) disclosure against the MSME payables ageing at year-end — a missed or under-stated disclosure surfaces as an audit qualification and creates re-assessment exposure under Section 143(3) in a subsequent scrutiny cycle.
- ▸ Section 16, MSMED Act 2006 — Interest on delayed payment — Where any buyer fails to make payment of the amount to the supplier as required under Section 15, the buyer shall, notwithstanding anything contained in any agreement between the buyer and the supplier or in any law for the time being in force, be liable to pay compound interest with monthly rests to the supplier on that amount from the appointed day at three times of the bank rate notified by the Reserve Bank. The interest is not deductible under Section 37 of the Income-tax Act by virtue of Section 23 of the MSMED Act, which means the interest cost sits on top of the Section 43B(h) disallowance as a separate non-deductible expense — the buyer's year-end exposure is the disallowance plus the compound interest plus the tax auditor's Clause 22 disclosure trail, not any one of these in isolation.