Mainboard IPO: Meaning, Eligibility and Key Benefits

A mainboard IPO is the first public sale of a company's equity shares, made when the company plans to list on the main trading platform of the NSE or BSE. It gives the company access to public capital and gives investors ownership in a business that has already cleared a defined set of regulatory checks.

Mainboard IPOs mobilised ₹1,60,273 crore between April and December 2025 (FY 2025-26), up from ₹1,46,534 crore in the same period a year earlier, according to the Economic Survey 2025-26. This scale makes it important to understand how the route works, who can use it, and what investors should check before applying.

What is a Mainboard IPO?

A mainboard IPO refers to an IPO routed for listing on the regular equity market of recognised exchanges such as NSE and BSE. It is governed by SEBI's mainboard IPO framework and the exchange's admission rules. It can take any of these three forms:

• Fresh issue: the company issues new shares and keeps the proceeds
• Offer for Sale (OFS): existing shareholders sell shares they already hold; the company receives nothing
• Combination issue: part fresh issue, part OFS, under one offer document

Once shares are allotted, they list on the exchange and trade freely in the secondary market. This is what separates "mainboard" from NSE Emerge and BSE SME, the platforms built for smaller issuers. You will need a demat account to hold whatever shares you're allotted.

Mainboard IPO Eligibility Criteria in India

Eligibility for a mainboard IPO is not decided by one common checklist. An issuer must meet SEBI’s ICDR requirements and the separate listing conditions of the exchange where it plans to list.

On March 21, 2026, SEBI introduced an amendment in its ICDR framework, which updated certain disclosure and lock-in provisions. The core financial eligibility conditions under Regulation 6(1) remained unchanged.

The first eligibility route is based on the issuer’s financial track record.

Route 1: Financial Track Record Under Regulation 6(1)

Under Regulation 6(1), an issuer can make a mainboard IPO if it meets the prescribed financial conditions. These include:

• Net tangible assets of at least ₹3 crore in each of the preceding three full years.
• Monetary assets capped at 50% of net tangible assets, except when the issue is entirely an OFS.
• Average operating profit of at least ₹15 crore during the preceding three years, with operating profit in each of those years.
• Net worth of at least ₹1 crore in each of the preceding three full years.
• An additional revenue condition if the issuer changed its name within the preceding year.

This route is used when the issuer has a clear operating and financial track record. But this is not the only way to access the mainboard IPO market.

Route 2: QIB-Led Route as per Regulation 6(2)

An issuer that does not meet the Regulation 6(1) conditions can still make a mainboard IPO under Regulation 6(2). This route is built to attract institutional participation.

The issue must be made through the book-building process, and at least 75% of the net offer must be allotted to Qualified Institutional Buyers, or QIBs. If this condition is not met, the application money must be refunded. The company cannot go ahead with a partial listing.

This route is important because it shows that a mainboard IPO is not limited only to companies that meet the standard profitability track record. The regulatory framework allows another route, but with a stronger institutional allocation requirement.

Lenskart used this route for its ₹7,278 crore IPO in November 2025. It reported a profit in FY25, but losses in FY23 and FY24 meant it did not have the three-year track record Route 1 requires.

Exchange-Level Requirements (NSE/BSE)

SEBI’s eligibility rules are only one part of the process. The issuer must also meet the listing conditions of the exchange where it plans to list.

For an NSE mainboard listing, key requirements include:

• Post-issue paid-up equity capital of at least ₹10 crore.
• Post-issue market capitalisation of at least ₹25 crore.
• A minimum three-year track record for the company, its promoters or a related business.
• No admitted winding-up petition, insolvency proceedings or material regulatory defaults.
• A proper investor grievance mechanism.

These exchange conditions should not be confused with SEBI’s Regulation 6(1) and 6(2) eligibility routes. SEBI decides the regulatory framework for the issue. The exchange decides whether the securities meet its listing admission conditions.

Mainboard IPO vs SME IPO

A mainboard IPO and an SME IPO both help companies access public capital. The difference lies in the listing platform, regulatory framework and capital conditions.

Key Benefits of a Mainboard IPO

A mainboard IPO has different benefits for the issuing company and for investors. These benefits should be understood as structural features, not as guarantees of return.

For companies:

• Large-scale capital in a single transaction, for expansion, debt reduction or capacity addition
• Governance and disclosure standards that build institutional trust
• An OFS route for existing shareholders to unlock value without diluting the company's balance sheet
• A public listing that eases all further capital raising

For investors:

• Ownership in businesses with an audited, multi-year financial history
• Comparatively higher post-listing liquidity than SME-platform stocks
• Standardised, SEBI-mandated disclosure in the offer document

These are structural features of the mainboard route. They do not guarantee allotment, listing gains, or investment returns. Prices of listed shares stay market-linked and can fall as easily as they rise.

What Should You Check Before Applying?

Before applying to a mainboard IPO, investors should look beyond subscription numbers and brand recall. The offer document is the most important starting point.

Check the following points:

• Whether the IPO is a fresh issue, an OFS or a combination of both.
• Who receives the money from the issue.
• What the objects of the issue say about the use of fresh proceeds.
• Revenue, profit and cash flow trends across multiple years.
• Debt levels and major financial obligations.
• Valuation compared with listed peers, where a fair comparison is available.
• Risk factors disclosed in the offer document.
• Promoter shareholding before and after the IPO.
• Whether the issuer used Regulation 6(1) or Regulation 6(2).

A heavily subscribed IPO is not automatically a good investment. A well-known company is also not automatically a suitable investment. The business, financials, valuation, and risks still need to support the decision.

Conclusion

A mainboard IPO is a regulated route to public capital, governed by SEBI's two eligibility tracks and separate exchange-level thresholds. The route an issuer takes, and how it plans to deploy the proceeds, say more than the "mainboard" label itself. Before applying to any issue, read its DRHP or RHP directly instead of relying on secondary summaries.

FAQs

Is every mainboard IPO from a profitable company?

No. Some issuers qualify through Regulation 6(1), which is based on financial track record. Others may use Regulation 6(2), where at least 75% of the net offer must be allotted to Qualified Institutional Buyers.

What is the difference between a fresh issue and an OFS?

In a fresh issue, the company issues new shares and receives the proceeds. In an OFS, existing shareholders sell shares they already hold and receive the proceeds. The company does not receive money from the OFS portion.

Does SEBI approval mean an IPO is a safe investment?

No. SEBI reviews the offer document for disclosure requirements. It does not certify that the IPO is a good investment or that investors will earn returns.

What is the minimum market capitalisation for an NSE mainboard listing?

For an NSE mainboard listing, post-issue market capitalisation must be at least ₹25 crore. This is separate from the minimum post-issue paid-up equity capital requirement of ₹10 crore.