Mainboard IPO versus SME IPO in India
The Indian public issue market operates on two parallel regulatory tracks: the mainboard, governed by Chapters II-VIII of the SEBI (ICDR) Regulations, 2018 , and the SME platform, governed by Chapter IX of the same regulations. Issuers self-select between these tracks based primarily on their post-issue paid-up capital: companies with paid-up capital above Rs 25 crore after the issue must list on the mainboard, while companies with paid-up capital of up to Rs 25 crore may choose the SME platform (ICDR Regulation 229). The two tracks differ substantially in eligibility criteria, disclosure burden, minimum lot sizes, investor category composition, post-listing obligations, and the market-making arrangement available to listed companies.
This article provides a structured comparison of the two tracks for the benefit of investors, issuers, and advisors evaluating the appropriate listing route. For standalone encyclopedic treatment of each track, see mainboard IPO and SME IPO .
Summary comparison table
| Attribute | Mainboard IPO | SME IPO |
|---|---|---|
| Governing regulation | SEBI ICDR 2018, Chapters II-VIII | SEBI ICDR 2018, Chapter IX |
| Exchange platform | NSE main, BSE main | NSE Emerge, BSE SME |
| Post-issue paid-up capital | No ceiling | Up to Rs 25 crore (Reg 229) |
| Profit test | Rs 15 crore average operating profit (Reg 6(1)), or the 75 per cent QIB route (Reg 6(2)) | EBITDA Rs 1 crore in two of three years (Reg 229(6), from 8 March 2025), plus SME exchange criteria |
| SEBI review | SEBI issues observations on the DRHP | None; the SME exchange reviews the draft (Reg 246(2)) |
| Public comment on draft | 21 days | 21 days (Reg 247(1), from 8 March 2025) |
| Disclosure schedule | ICDR Schedule VI Part A | ICDR Schedule VI Part A, plus EPF and ESIC details, lead manager’s site visit report and fees (Reg 245(2)) |
| Minimum application | Rs 10,000 to Rs 15,000 (Reg 47(2)) | Two lots, above Rs 2 lakh (Reg 267(2), from 8 March 2025) |
| QIB allocation | At most 50% (Reg 6(1) issuer) | At most 50% (Reg 253(1)) |
| NII allocation | At least 15% | At least 15% (Reg 253(1)) |
| Small-investor allocation | At least 35% to retail individual investors | At least 35% to individuals applying for the minimum application size |
| Anchor investor minimum | Rs 10 crore per anchor | Rs 2 crore per anchor (Reg 2(1)(c)) |
| Offer for sale | No cap for a Reg 6(1) issuer | Up to 20% of issue; each seller at most 50% of its holding (Reg 230(1)(f), (g)) |
| Underwriting | Under Reg 40 | 100% compulsory; lead manager 15% on own account (Reg 260) |
| Market making obligation | None | 3 years from listing (Reg 261) |
| Promoter lock-in | 18 months on minimum contribution; 6 months on excess | 3 years on minimum contribution; excess 50% for 1 year and 50% for 2 years (Reg 238, from 8 March 2025) |
| Minimum allottees | 1,000 | 200 (Reg 268(1), from 8 March 2025) |
| Financial results | Quarterly | Half-yearly (LODR Reg 33(5)) |
| Governance provisions | LODR Regs 17 to 27 apply | Exempt under LODR Reg 15(2)(b), except Reg 23 above Rs 10 crore paid-up or Rs 25 crore net worth |
| Migration | Not applicable | To mainboard with paid-up capital above Rs 10 crore and up to Rs 25 crore (Reg 277) |
Eligibility: the paid-up capital threshold
The most fundamental distinction between the two tracks is the post-issue paid-up capital ceiling. A company planning an issue that will result in a post-issue paid-up capital above Rs 25 crore must list on the mainboard. The Rs 25 crore ceiling is based on the nominal value of all outstanding equity shares after the issue (including shares being issued and any pre-issue shares), not on the market capitalisation.
In practice, many companies design their pre-IPO capital structure specifically to stay under or above this threshold, depending on which track they prefer. A company that wants the SME platform’s lighter disclosure burden but is growing toward Rs 25 crore in paid-up capital may time its IPO to precede the threshold breach; a company that has already crossed Rs 25 crore has no choice but to list on the mainboard.
Disclosure burden
The disclosure schedule is the same on both tracks: an SME offer document must carry the disclosures in Part A of Schedule VI of the ICDR Regulations (Regulation 245(2)(b)), as a mainboard RHP does. The difference is the reviewer. SEBI issues observations on a mainboard DRHP, while for an SME issue it issues none (Regulation 246(2)) and the SME exchange reviews the draft. Since 8 March 2025 an SME draft must also stay open for 21 days of public comment (Regulation 247(1)) and carry EPF and ESIC details, the lead manager’s site visit report and the lead manager’s fees (Regulation 245(2)(c) to (e)).
Minimum lot size and investor base implications
The most visible difference from a retail investor’s perspective is the minimum lot size. Mainboard IPOs are designed with a minimum lot equivalent to approximately Rs 10,000-Rs 15,000 at the issue price, ensuring broad retail participation. SME IPOs require a minimum application of two lots, above Rs 2 lakh (ICDR Regulation 267(2), effective 8 March 2025; earlier Rs 1 lakh), so even the smallest SME bid is at the mainboard retail ceiling.
The higher SME lot size means:
- An SME IPO with 1,00,000 retail applications has a much smaller number of eligible applicants than a comparable mainboard issue with 30 lakh retail applications.
- Oversubscription multiples in popular SME issues are computed against a smaller tranche and a smaller applicant universe, which can make 60×-100× subscription in an SME issue correspond to a narrower pool of actual capital than the same multiple in a mainboard issue.
- An individual investor in an SME IPO applies for exactly two lots, the minimum application size; a larger bid is classified as non-institutional. Bids up to Rs 5 lakh can be placed through UPI ASBA .
Market making and liquidity
Mainboard-listed shares benefit from the full depth of the NSE/BSE main-market order book, with multiple market participants, algorithmic trading, institutional participation, and analyst coverage. There is no mandatory market-making obligation on the mainboard; liquidity emerges from the breadth of the investor base.
SME-listed shares rely on compulsory market making for three years from listing, which the lead manager must arrange through stock brokers of the SME exchange appointed by the issuer (ICDR Regulation 261(1)). On the allotment date the market maker must hold at least 5 per cent of the shares proposed to be listed (Regulation 261(4)). This engineered liquidity is a necessary substitute for the natural liquidity that is absent in a thinly traded SME stock. Once the three-year market-making period lapses, liquidity depends entirely on the trading interest that has developed organically.
Post-listing obligations
Mainboard-listed companies are subject to the full SEBI (Listing Obligations and Disclosure Requirements) Regulations, 2015 (LODR), which require:
- Quarterly and annual financial disclosures.
- Immediate disclosure of material developments (Regulation 30 of LODR).
- Constituted audit committee, nomination and remuneration committee, and stakeholders’ relationship committee.
- Minimum independent director representation on the board.
- Annual general meeting within six months of financial year end.
- Related-party transaction approval above LODR thresholds must be put to shareholder vote.
SME-listed companies are subject to a lighter LODR framework: half-yearly rather than quarterly financial results (LODR Regulation 33(5)), and exemption from the governance provisions of Regulations 17 to 27 (Regulation 15(2)(b)), except that from 1 April 2025 Regulation 23 on related-party transactions applies where paid-up capital exceeds Rs 10 crore or net worth exceeds Rs 25 crore. This lighter burden is a deliberate regulatory subsidy to SME companies that may lack the governance and financial infrastructure to comply with full LODR.
Migration from SME to mainboard
An SME-listed company whose post-issue paid-up capital is more than Rs 10 crore and up to Rs 25 crore may migrate to the mainboard under ICDR Regulation 277 if it meets the mainboard listing criteria and its shareholders pass a special resolution by postal ballot in which non-promoter votes in favour are at least twice the non-promoter votes against. Migration brings the company into the full LODR framework.
SEBI’s consultation paper of 19 November 2024 counted 322 migrations from the SME platforms to the mainboard up to 15 October 2024: 140 from NSE Emerge and 182 from BSE SME.
Investor considerations
For retail investors, the choice of which IPO type to participate in carries distinct risk profiles:
Mainboard IPOs typically have lower per-application minimum investment, broader analyst and media coverage, lower relative risk of price manipulation (because of stricter surveillance and broader investor base), and more predictable secondary-market liquidity.
SME IPOs carry a higher minimum investment, limited analyst coverage, higher price volatility around listing (both on the upside and downside), and dependence on the market maker for liquidity during the first three years. The historical pattern of very high listing-day gains in popular SME issues has attracted speculative retail interest, but many such gains are not sustained, and SME investors who are unable to sell on listing day may face illiquid secondary markets.
SEBI’s investor advisory of 28 August 2024 (press release 18/2024) warned that some SME companies and promoters “project an unrealistic picture of their operations” after listing, and told investors not to rely on unverified social media posts or invest on tips and rumours.
The role of media coverage in the mainboard vs. SME distinction
Mainboard IPOs receive substantially more media and analyst coverage than SME IPOs, which itself creates a secondary information asymmetry between investors in the two segments.
Mainboard media coverage: a major mainboard IPO will typically be covered by the business correspondents of all major Indian financial newspapers (Economic Times, Business Standard, Mint, Financial Express) and business TV channels (CNBC-TV18, ET Now, Bloomberg Quint). The coverage includes DRHP analysis when filed, RHP analysis when the issue opens, live subscription data commentary during the window, and listing-day coverage. Multiple brokerage research notes are published, and IPO review websites provide standardised ratings.
SME media coverage: most SME IPOs receive no coverage from mainboard-focused financial media. Specialist SME IPO websites (such as chittorgarh.com, smedirectory.in, and ipowatch.in) track SME issues, but their reach and analytical depth are more limited. Many retail investors in SME IPOs make decisions based entirely on social media commentary, peer recommendations, and informal grey-market signals, with very limited analytical foundation.
This coverage gap is one of the structural arguments for the higher SME lot size: if retail investors cannot access quality independent analysis of an SME IPO, the higher minimum investment serves as a friction that limits the scale of potential mis-selling.
The mainboard vs. SME distinction in the context of corporate governance
One of the substantive differences between mainboard and SME-listed companies is the corporate governance framework that applies post-listing.
Mainboard LODR obligations
A mainboard-listed company must comply with the full SEBI (LODR) Regulations, 2015, including:
- An audit committee with a majority of independent directors.
- A nomination and remuneration committee to set executive pay.
- A stakeholders’ relationship committee to handle investor grievances.
- A risk management committee for the top 1,000 listed companies by market capitalisation.
- Board-level gender diversity (at least one independent woman director).
- Annual general meetings within six months of financial year end.
- Quarterly financial result disclosures within 60 days of quarter end.
- Related-party transactions above specified thresholds must be approved by shareholders in a meeting where related parties abstain from voting.
- CEO/CFO certifications on the accuracy of financial statements.
SME LODR obligations
SME-listed companies are subject to a lighter version of the LODR framework. Key differences:
- Half-yearly financial results instead of quarterly, with no year-to-date results (LODR Regulation 33(5)).
- Exemption from the board, committee and other governance provisions of Regulations 17 to 27 (Regulation 15(2)(b)).
- Related-party rules in Regulation 23 apply only from 1 April 2025, and only where paid-up capital exceeds Rs 10 crore or net worth exceeds Rs 25 crore.
The corporate-governance gap between mainboard and SME is shrinking over time as SEBI’s SME reforms have tightened some requirements, but meaningful differences remain. Investors in SME-listed companies should be aware that the continuous disclosure and governance accountability of an SME company is lower than for a comparable mainboard company.
References
- Securities and Exchange Board of India (Issue of Capital and Disclosure Requirements) Regulations, 2018, Chapters II-IX.
- SEBI, Consultation paper on review of SME segment framework under SEBI (ICDR) Regulations 2018, 19 November 2024, and SEBI (ICDR) (Amendment) Regulations 2025, effective 8 March 2025.
- Securities and Exchange Board of India (Listing Obligations and Disclosure Requirements) Regulations, 2015.
- SEBI, Annual Report 2023-24, SME platform statistics.
- NSE Emerge platform guidelines, available at nseindia.com.
- BSE SME platform guidelines, available at bsesme.com.
See also
- Mainboard IPO , detailed article on the mainboard track
- SME IPO , detailed article on the SME track
- Book running lead manager , the intermediary common to both tracks
- Book building , the price-discovery process common to both tracks
- IPO lot size , the key differentiator for retail investors
- Anchor investor , permitted on both tracks, lower minimum on SME
- UPI ASBA , the retail application channel common to both tracks
- IPO listing day , the T+3 listing process common to both tracks
- Basis of allotment , the allotment methodology common to both tracks
- National Stock Exchange , operator of both NSE main and NSE Emerge
- Bombay Stock Exchange , operator of both BSE main and BSE SME