What Is IPO GMP? Grey Market Premium Explained Simply

IPO GMP (grey market premium) is the amount above the issue price at which informal dealers say they will buy a company's IPO shares before they list. People add it to the issue price to guess the listing price. It is unofficial and unregulated: these trades happen outside the stock exchanges and outside SEBI's investor-protection system, the numbers cannot be verified, and as of October 2026 they remain a weak guide for any investment decision.

How the grey market works

Between the IPO opening and listing, there is no official market for the shares. A grey market fills that gap informally. Dealers, often operating through phone and messaging networks, quote prices for shares that do not yet exist in anyone's demat account. Deals are settled privately after listing, on trust.

Because no exchange records these trades, a GMP figure on a website is simply what someone says dealers are quoting. Two websites can show different premiums for the same issue on the same day.

The three common grey market quotes

• GMP (premium per share): the price above the issue price a dealer offers for shares to be delivered after listing.
• Kostak rate: a fixed sum paid for your whole application, whether or not you get shares. If you sell your application for a kostak rate, you must hand over the shares (and the profit or loss on them) if allotted.
• Subject-to-sauda rate: paid only if your application gets an allotment.

Selling an application or shares this way means sharing your PAN, application and demat details with an unregulated party and relying on a verbal promise. If the dealer does not pay, you have no remedy.

How "estimated listing price" is calculated

Websites usually compute:

Estimated listing price = upper end of price band + GMP

Estimated listing gain % = GMP ÷ upper end of price band × 100

Worked example (illustrative)

An issue has a price band of ₹270 to ₹285 and a lot size of 52 shares. A website shows a GMP of ₹40.

Now suppose the market weakens before listing and the shares open at ₹290.

If the shares opened at ₹270, the investor would show a loss of 52 × ₹15 = ₹780 per lot, even though GMP had suggested a 14% gain. And most retail applicants in an oversubscribed issue get either one lot or none, so a "₹2,080 per lot" headline is not what most people actually earn.

You can track issue dates and listing results on our live IPO dashboard. Compare the listing price with the issue price there, not with an earlier GMP figure.

Why GMP is not reliable

1. No verification. There is no public order book. A quote can come from a handful of trades or none at all.
2. Easy to influence. In small issues, especially SME IPOs, a few people talking up a premium can create a buzz that pulls in more applications. Thin markets are the easiest to push around.
3. It changes fast. GMP often moves sharply in the days between closing and listing, following the broader market and subscription numbers.
4. It reflects sentiment, not value. GMP says nothing about the company's earnings, debt or valuation. That is in the red herring prospectus; see how to read the IPO offer document.
5. Counterparty risk. Any money you make in the grey market depends on an unregulated dealer paying you.
6. It is not a SEBI number. SEBI does not publish, track or endorse GMP. Media and broker reports note that it is outside SEBI's framework, and SEBI has publicly discussed giving investors a regulated way to trade shares between allotment and listing to curb grey market activity. Check SEBI's latest circulars for the status of that idea.

Better things to check than GMP

Subscription numbers are official, unlike GMP, but they also measure demand rather than value. A heavily oversubscribed issue can still fall after listing.

Why GMP and listing often diverge

Several things happen between the last GMP quote and the opening bell that a grey market figure cannot capture:

• Final subscription data. QIB demand on the last day often shifts sentiment sharply, up or down.
• Market mood on listing day. A weak Nifty or Sensex opening drags new listings down regardless of earlier chatter.
• Supply from allottees. In heavily subscribed issues, many allottees sell at the open to book gains, which can cap the opening price.
• Exchange price discovery. Listing prices come from a special pre-open session on NSE and BSE, based on real orders, not dealer quotes.

So even a GMP figure quoted in good faith is a snapshot of informal sentiment, not a forecast.

Red flags around GMP

• Messages promising "assured listing gains" or offering to buy your application.
• Requests for your PAN, demat ID or OTP to "lock in" a kostak deal.
• Paid groups selling GMP "tips" or allotment guarantees.

Our guide on how to spot investment scams covers how to report such offers. If you do invest in an IPO and hold it, judge the result by your annualised return with our CAGR calculator, not by whether it beat a grey market guess.

This article is educational. It does not recommend any IPO or any grey market activity.

Key takeaways

• GMP is an unofficial premium quoted by informal dealers before listing; no exchange or regulator sets it.
• Estimated listing price = upper price band + GMP; the gain % is GMP ÷ upper band.
• Grey market deals are unregulated, unrecorded and not legally enforceable.
• GMP changes quickly, varies by source and is easy to influence in small issues.
• Base decisions on the RHP and official subscription data, not GMP.
• Never share PAN, demat or OTP details to sell an IPO application.