Bulk Deal vs Block Deal: What is the difference

You open your trading app one morning and a stock you have been watching has jumped 4%. No news. No results. The volume bar is enormous. You wonder if you missed something.

You did not miss the news. You probably missed a bulk deal. And that one term explains more about the day's price move than anything else you will find.

Quick summary

• A bulk deal happens when someone buys or sells 0.5% or more of a company's total listed shares in regular trading hours. It shows up on your volume chart in real time.
• A block deal is a large privately negotiated trade worth at least ₹25 crore in a single transaction, executed in a separate window before the market opens or in the afternoon. It does not appear on your chart while it is happening.
• Bulk deals can move the stock price immediately because they happen in the open market. Block deals are designed to avoid moving the price.
• Both deal types are disclosed to the public after execution. The privacy of a block deal is only during execution, not permanently.
• When a company's founder or major shareholder sells via a block deal, it is worth investigating why. When an institution buys via one, it often signals conviction. Who is trading matters as much as how much.
• Neither deal type is a buy signal. Both are research signals.

What is a bulk deal?

A bulk deal is any trade where a single investor, or a group acting together under one client code, buys or sells 0.5% or more of a company's total listed shares in a single trading session. It happens in the regular market during normal hours, from 9:15 AM to 3:30 PM, alongside every other retail order.

Think of it like a large customer walking into a regular grocery store and buying out half the stock of one item. Everyone in the store sees it happening. The shelves empty. The price adjusts. Other customers react.

That is what a bulk deal looks like on your chart: a sudden spike in volume, often accompanied by a sharp price move, because the large order is absorbing available shares from the regular order book.

The broker handling the trade is required to report it to the stock exchange immediately if it happened in a single transaction, or within one hour of market close if it was done across multiple smaller trades. The exchange then publishes the buyer and seller names publicly, usually the same evening. You can find this data on the NSE and BSE websites under the "Bulk Deals" section, updated daily after market hours.

Unlike block deal orders, a bulk deal order that is not fully filled does not get cancelled at the end of a window. It remains active in the order book until it finds matching supply or demand, which is exactly why large bulk orders can sustain price momentum for extended stretches of a trading session.

Why do institutions use bulk deals?

Bulk deals serve three main purposes: portfolio rebalancing when a fund adjusts weights across stocks, building or exiting a position when an institution has a directional view, and market-making activity where large participants provide liquidity. Mutual funds, domestic institutions, and large HNIs are the most common participants, though retail investors can technically trigger a bulk deal threshold in smaller companies if their transaction crosses the 0.5% mark.

What are the benefits of bulk deals?

Bulk deals offer three concrete advantages that make them the preferred route for institutions comfortable with market visibility.

The first is flexibility. A bulk deal can be executed at any point during regular trading hours, with no appointment needed and no dependency on a counterparty showing up in a fixed window. If an institution has a strong view and wants to act immediately, the open market lets them move.

The second is transparency for the other side. Because bulk deals are visible on charts in real time and disclosed by name after market close, they function as a public confidence signal. When a well-regarded fund appears as the buyer in a bulk deal, it tells the market something about their conviction at that price. That signal has value both for the buyer building credibility and for the retail investor doing research.

The third is cost. Bulk deals in the regular market carry standard brokerage and STT with no additional execution fee for using a special window. For institutions with high-volume trading desks, keeping execution simple and cost-predictable matters.

What is a block deal?

A block deal is a large, privately negotiated transaction between two parties, worth at least ₹25 crore or 5,00,000 shares in a single trade, per the SEBI circular effective December 7, 2025. The ₹25 crore threshold was raised from the earlier ₹10 crore, reflecting the growth of India's institutional market. The 5,00,000-share alternative threshold means that in smaller companies with lower share prices, the volume trigger can kick in before the value threshold does.

Unlike a bulk deal, block deals do not happen during regular trading hours. They take place in two exclusive 15-minute windows: a morning session from 8:45 AM to 9:00 AM, and an afternoon session from 2:05 PM to 2:20 PM. These windows exist specifically to keep large trades out of the live order book where they would move the price.

During these windows, trades must be executed within a narrow price band of plus or minus 3% of the stock's reference price. This prevents either party from using the private window to execute at a dramatically off-market price. Critically, 100% delivery is mandatory. Every share bought must be taken into the buyer's Demat account. There is no intraday squaring off. This rule exists to ensure that only investors with genuine long-term intent use the block window.

If a block deal order is placed in the morning window and does not find a matching counterparty, it is cancelled outright. It does not carry forward to the afternoon session. Both sides must show up.

Block deals are invisible on your regular trading charts while they are happening. But the exchange publishes the full details, including the buyer's and seller's names and the transaction price, immediately after execution. This is also available on NSE and BSE websites.

Why do institutions use block deals?

Block deals are the preferred route when large investors want to rebalance exposure to a specific stock or sector without alerting the broader market. A mutual fund exiting a large position in a mid-cap stock can use the block window to find a willing buyer without driving the price down through public selling pressure. Foreign Portfolio Investors (FPIs), promoters, and large insurance funds use this route for the same reason: execution without market disruption. The purpose is not secrecy from regulators, it is price efficiency for both buyer and seller.

What are the benefits of block deals?

Block deals solve a specific problem that bulk deals cannot: how to move a very large position without the market moving against you while you do it.

The most important benefit is price stability during execution. Because the trade happens in a private window outside the live order book, a fund selling ₹200 crore of a mid-cap stock does not trigger a cascade of stop-losses and panic selling on its way out. Both buyer and seller agree on a price before the market sees anything. By the time the disclosure hits, the transaction is complete.

The second benefit is certainty of execution. The price band of plus or minus 3% from the reference price means both parties know the range before they enter the window. There are no surprise fills at dramatically worse prices.

The third benefit is the delivery requirement itself. Because 100% delivery is mandatory, every block deal that closes represents a genuine, fully funded commitment by the buyer. No leverage, no intraday speculation. This makes the disclosed block deal data more meaningful as a research input than a bulk deal, which can include intraday traders with no intention of holding overnight.

Bulk deal vs block deal: side by side

One nuance worth knowing: a bulk deal can also be executed inside the block deal window if it meets both sets of criteria. An investor who wants to buy 0.5% of a company's shares and also wants privacy can choose the block window over the open market. The exchange classifies it by whichever rule it triggers.

How to read these deals as a retail investor

Meet Kavya, a 28-year-old marketing manager from Pune who started investing two years ago through DreamStreet. She follows a few mid-cap companies and checks NSE bulk deal data every evening. She does not chase every bulk deal she sees. She looks for patterns.

Here is the framework she uses, and the one most experienced investors implicitly follow.

Institutional buying is generally a positive signal. When a mutual fund or foreign institutional investor (FII) buys a large block in a company, they have typically done significant research before committing that capital. They are not speculating. A ₹50 crore block purchase by a well-known fund is not a guarantee, but it is worth examining why they found the stock interesting at that price.

Promoter selling via a block deal is worth investigating. When the founder or majority owner sells a large stake through a block window, that is not automatically bad. Promoters sell for many reasons: estate planning, diversification, personal liquidity. But if promoter holding has been falling steadily through repeated block deals, it is a meaningful signal that warrants checking. A promoter who is genuinely confident about the company's next two years rarely rushes to reduce their stake.

Single trades mean less than patterns. One bulk deal buy does not mean an institution has conviction. Five bulk buys over three weeks in the same stock, with no corresponding sells, is a different story.

The price of the deal relative to the market price matters. A block deal executed at a 2% premium to the previous day's closing price suggests the buyer wanted those shares enough to pay above market. A deal at a discount might mean the seller was eager to exit quickly.

What buying the noise actually costs you

It is tempting to react immediately when you see a big bulk deal and jump in hoping to catch the momentum. Before you do, run the full cost calculation.

Meet Rohit, a 24-year-old software engineer from Rajkot with a ₹50,000 portfolio spread across six stocks. He sees a bulk deal in one of his holdings and decides to sell his other five positions to concentrate. Here is what that decision costs before he even places the new buy order.

He pays a Depository Participant (DP) charge every time shares leave his Demat account. That charge is flat, typically ₹15 to ₹20 including GST, and it is per company per day of selling, regardless of how many shares he sells. On DreamStreet, the DP charge applies the same way — it is a depository fee that no platform can waive. Selling five positions means five separate DP charges, around ₹75 to ₹100, applied to his principal before he has bought anything.

If he held any of those positions for under 12 months, any profit he made is a Short-Term Capital Gain, taxed at 20%. On a ₹5,000 gain, he pays ₹1,000 in tax.

By the time he accounts for DP charges on the sell side, brokerage on both sides, and STCG tax, the bulk deal he is chasing needs to move significantly just for him to break even.

The math almost never works for small position sizes. Large institutional trades are signals to research, not triggers to trade.

Frequently asked questions

What is the main difference between a bulk deal and a block deal?
A bulk deal involves buying or selling 0.5% or more of a company's total listed shares during regular market hours. A block deal is a privately negotiated transaction worth at least ₹25 crore or 5,00,000 shares, executed in a dedicated 15-minute window separate from the live market. Bulk deals are visible in real time and can move the price immediately. Block deals are hidden while they happen and are designed to avoid immediate price impact, though full details are disclosed publicly after execution.

Why was the block deal threshold changed to ₹25 crore?
SEBI raised the minimum block deal size from ₹10 crore to ₹25 crore via a circular effective December 7, 2025. The change reflects the significant growth in India's institutional investment base and is intended to restrict the block window to genuinely large institutional trades, preventing mid-sized investors from using the private window for moderately sized transactions.

Can retail investors participate in block deals?
In practice, no. The ₹25 crore minimum means block deals are accessible only to institutional investors, large mutual funds, foreign portfolio investors, and high-net-worth individuals. Retail investors trade through the regular order book.

What happens if a block deal order is not matched?
Unmatched block deal orders are cancelled at the end of each window. A morning session order that finds no counterparty is cancelled entirely. It does not carry forward to the afternoon session. Both buyer and seller must be present in the same window for execution to happen. This is different from bulk deal orders, which remain in the regular order book until filled.

Are block deals completely private?
Only during execution. Block deals are not visible on live trading charts while the window is open. However, the exchange publishes the full details, including buyer name, seller name, quantity, and price, immediately after execution. Bulk deal disclosures follow the same day, usually by evening. Neither deal type remains hidden from the public permanently.

Should I buy a stock just because a big institution bought it in a block deal?
No. Use institutional block buys as a prompt to research the company, not as a direct trading signal. Large institutions have different risk profiles, portfolio sizes, and time horizons than retail investors. They also have information you may not. What looks like a good entry for a ₹500 crore fund may not be the right position size or holding period for your portfolio.

How are profits from trading based on bulk or block deal news taxed?
Gains on equity shares held for under 12 months are Short-Term Capital Gains, taxed at 20%. Gains on shares held over 12 months are Long-Term Capital Gains, taxed at 12.5% on amounts exceeding ₹1.25 lakh per financial year. The ₹1.25 lakh exemption applies only to long-term gains.

Where can I find bulk and block deal data?
Both NSE and BSE publish bulk and block deal disclosures on their official websites daily. On NSE, go to the Market Data section and look for Bulk Deals and Block Deals under the equity segment. Data includes the company name, buyer or seller name, quantity, and price. This is updated every trading day after market hours. If you invest through DreamStreet, you can also track which stocks in your watchlist have seen recent bulk or block deal activity directly in the app.

Disclaimer: This article is for educational purposes only and does not constitute financial or investment advice. SEBI rules referenced are based on circulars effective as of April 2026. Please consult a SEBI-registered financial advisor before making investment decisions.