How MSME Delayed Payment Interest Is Calculated Under Section 16 of the MSMED Act 2006
A precise, law-based explanation of how compound interest accrues on delayed payments to MSME suppliers — with formula, real examples using current RBI Bank Rate, and the legal sections that make this enforceable.
When a buyer delays payment to an MSME supplier beyond the agreed period, Section 16 of the Micro, Small and Medium Enterprises Development (MSMED) Act 2006 mandates compound interest with monthly rests at three times the RBI Bank Rate on the outstanding amount. As of February 2023, the RBI Bank Rate is 6.75%, making the applicable MSME interest rate 20.25% per annum, compounded monthly.
This is not optional. The Act does not require a court order for interest to accrue — it accrues automatically from the day after the agreed payment period expires. The buyer is legally liable for this amount whether or not they acknowledge it.
The Legal Foundation: Sections 15 and 16 of the MSMED Act 2006
Two sections of the MSMED Act govern delayed payment interest. Understanding both is essential before any calculation.
"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."
"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 or, as the case may be, from the date immediately following the date agreed upon, at three times of the bank rate notified by the Reserve Bank."
Key phrase: "notwithstanding anything contained in any agreement"
The buyer cannot contractually waive their obligation to pay this interest. Any such clause in a purchase order or contract is void.
The Formula: How MSME Delayed Payment Interest Is Calculated
Section 16 requires compound interest with monthly rests. This is standard compound interest formula applied monthly (12 periods per year).
Formula
A = P × (1 + r/n)n×t
A = Total amount payable (principal + interest)
P = Principal invoice amount
r = Annual interest rate = 3 × RBI Bank Rate
n = 12 (monthly compounding)
t = Time in years (days delayed ÷ 365)
Interest = A − P
Why monthly compounding matters: On a ₹5,00,000 invoice delayed 60 days at 20.25% p.a., monthly compounding gives ₹16,768 in interest vs ₹16,644 with simple interest — a ₹124 difference. Over larger amounts and longer delays, this gap grows significantly.
Real Calculation Examples — MSME Delayed Payment Interest
Three representative examples showing how Section 16 interest accrues across different invoice sizes and delay durations. All use the current RBI Bank Rate of 6.75% (MSME rate: 20.25% p.a.), monthly compounding.
Example 1: IT Services Invoice — 45 Days Overdue
Typical scenario for software/consulting firms
Invoice Details
Interest Calculation
Example 2: Manufacturing Supply Invoice — 90 Days Overdue
Common in auto-ancillary and industrial supply chains
Invoice Details
Interest Calculation
Example 3: Construction Subcontractor — 180 Days Overdue
Infrastructure and real estate payment delays — a chronic problem
Invoice Details
Interest Calculation
Quick Reference: Interest on ₹1,00,000 at Current MSME Rate (20.25% p.a.)
| Delay Period | Interest Amount | Total Payable | % of Principal |
|---|---|---|---|
| 30 days | ₹1,659 | ₹1,01,659 | 1.66% |
| 45 days | ₹2,511 | ₹1,02,511 | 2.51% |
| 60 days | ₹3,368 | ₹1,03,368 | 3.37% |
| 90 days | ₹5,094 | ₹1,05,094 | 5.09% |
| 180 days | ₹10,447 | ₹1,10,447 | 10.45% |
| 365 days | ₹22,421 | ₹1,22,421 | 22.42% |
Based on RBI Bank Rate 6.75% × 3 = 20.25% p.a., monthly compounding. Principal: ₹1,00,000.
Common Mistakes When Calculating MSME Delayed Payment Interest
Most MSME interest calculations circulating on the internet contain one or more of these errors. They result in either understated claims (leaving money on the table) or overstated claims (which a court will reduce).
Using Repo Rate instead of Bank Rate
Repo Rate (currently 6.50%) is lower than Bank Rate (6.75%). Using Repo Rate understates MSME interest by about 1.1% p.a. The MSMED Act explicitly says 'bank rate notified by Reserve Bank' — this is the Bank Rate, not the Repo Rate.
High impactUsing simple interest instead of compound
Section 16 says 'compound interest with monthly rests.' Using simple interest understates the claim. On a ₹10 lakh invoice delayed 12 months, compound (monthly) gives ₹2,24,210 vs simple interest at ₹2,02,500 — a ₹21,710 difference.
High impactStarting interest from invoice date, not day after due date
Interest begins the day immediately after the agreed payment period expires — not from the invoice date. Starting from invoice date overstates the claim and a court will reduce it to the correct date.
Medium impactIgnoring the 45-day cap on payment agreements
If the purchase order or agreement specifies a 90-day payment term, that clause is void under Section 15 of the MSMED Act. Interest starts after 45 days regardless of what the contract says — but claiming from day 46 requires you to assert the 45-day rule explicitly.
Medium impactCalculating without Udyam Registration
The MSMED Act only protects registered MSMEs. If your Udyam Registration certificate was obtained after the invoice date, your protection under Section 16 may not apply to that invoice. Registration date matters, not just current registration status.
High impactUsing a static RBI Bank Rate instead of the date-correct rate
The RBI Bank Rate changed multiple times between 2019 and 2023. Using the current rate for an invoice from 2020 is incorrect. The rate applicable on the date the payment was due should be used for calculations involving that invoice.
Medium impactMSME Samadhaan: How to Enforce Your Interest Claim
Calculating interest is step one. Recovering it requires filing a reference on the MSME Samadhaan portal — the government's online dispute resolution platform for MSME payment disputes.
Filing Process — Summary
Verify MSME Registration
Confirm you have a valid Udyam Registration Certificate that predates the invoice in question.
Calculate Interest
Use the MSMED Act Section 16 formula: 3× RBI Bank Rate, monthly compounding, from day after due date.
Send Formal Demand Notice
Issue a written demand to the buyer citing the invoice, due date, days delayed, interest calculated, and the specific MSMED Act sections. Keep proof of delivery.
File on MSME Samadhaan
File at samadhaan.msme.gov.in with invoice copies, delivery proof, and your interest calculation. No court fees or advocate required at this stage.
MSME Facilitation Council Conciliation
The MSME Facilitation Council (MFC) will attempt conciliation first. If settled, the agreed amount (including interest) is binding.
Arbitration if Conciliation Fails
If conciliation fails within 45 days, the MFC proceeds to arbitration under the Arbitration and Conciliation Act 1996. Awards are final and executable as a court decree.
Frequently Asked Questions
Methodology & Data Sources
Interest Formula: Compound interest with monthly rests — A = P × (1 + r/12)^(12t). Rate r = 3 × RBI Bank Rate as of due date. As mandated by Section 16, MSMED Act 2006.
RBI Bank Rate Data: RBI Monetary Policy Press Releases ↗ — rates maintained from 2016 to present.
Legal Source: Micro, Small and Medium Enterprises Development Act 2006, Sections 15 and 16. Ministry of MSME, Government of India.
Data Reviewed by: invoicefollowups.com Research Team
Last Updated: May 2025
Disclaimer: This calculator provides indicative calculations for reference. Actual amounts may vary based on specific agreement terms, applicable RBI rate on dispute date, and legal interpretation. This does not constitute legal advice. Consult a CA or legal advisor for formal proceedings.
Official Sources: MSME.gov.in ↗, MSME Samadhaan ↗, RBI.org.in ↗