Reviewed on 24 Oct 2026 · Source: IPO Bulletin explainer; checked against SEBI ICDR Regulations 2018 (as amended) and exchange listing rules
A mainboard IPO is a public issue by a company that lists on the main platform of the BSE or the NSE, as opposed to the SME platforms made for smaller businesses. Mainboard companies must meet stricter eligibility tests set by SEBI, including a track record of operating profit, minimum net worth and a minimum post-issue market capitalisation, or alternatively use the route in which at least 75 percent of the issue is allotted to qualified institutional buyers. Issue sizes are larger, disclosure is more extensive, and the shares are generally more liquid after listing, because a bigger number of investors, funds and analysts follow them. Retail investors can apply for up to Rs 2 lakh, a lot normally costs around Rs 14,000 to Rs 15,000, and there is no mandatory market maker. Mainboard companies are also included in the broader indices after meeting criteria and are subject to continuing disclosure norms under the listing regulations. A mainboard listing is no guarantee of quality, but the checks are heavier than for SME issues. IPO Bulletin separates mainboard and SME IPOs on its pages so that investors can compare like with like.
Example: A manufacturing company with three years of profits raises Rs 800 crore through a mainboard IPO and lists on both the NSE and BSE main boards. A small firm raising Rs 20 crore lists on the SME platform instead.
A mainboard IPO is a public issue by a company that lists on the main platform of the BSE or the NSE, as opposed to the SME platforms made for smaller businesses. Mainboard companies must meet stricter eligibility tests set by SEBI, including a track record of operating profit, minimum net worth and a minimum post-issue market capitalisation, or alternatively use the route in which at least 75 percent of the issue is allotted to qualified institutional buyers. Issue sizes are larger, disclosure is more extensive, and the shares are generally more liquid after listing, because a bigger number of investors, funds and analysts follow them. Retail investors can apply for up to Rs 2 lakh, a lot normally costs around Rs 14,000 to Rs 15,000, and there is no mandatory market maker. Mainboard companies are also included in the broader indices after meeting criteria and are subject to continuing disclosure norms under the listing regulations. A mainboard listing is no guarantee of quality, but the checks are heavier than for SME issues. IPO Bulletin separates mainboard and SME IPOs on its pages so that investors can compare like with like.
A market maker is a broker-dealer that is obliged to keep buying and selling the shares of a particular company so that investors can always find a buyer or seller. In India, market makers are mandatory for SME IPOs. The lead manager appoints at least one market maker, who commits to quoting two-way prices for the shares for a minimum period, typically three years from listing, and to maintain a minimum quote size and a maximum spread between the buy and sell price. This is needed because small-company shares trade thinly, and without a market maker a seller might not find any buyer at all. The market maker usually receives a part of the issue, often around five percent, as a reserved portion so that it can start with some inventory. It earns its income from the spread between buy and sell prices. For investors the presence of a market maker supports liquidity but does not protect against price falls. The name of the market maker and the reserved portion are stated in the offer document and shown on IPO Bulletin's SME IPO pages.
Worked example
A manufacturing company with three years of profits raises Rs 800 crore through a mainboard IPO and lists on both the NSE and BSE main boards. A small firm raising Rs 20 crore lists on the SME platform instead.
