Block Deal vs Bulk Deal: What the Disclosure Really Tells You

A single line scrolls across your trading app: "Bulk deal alert — 12 lakh shares bought." Your first instinct is that a big investor is accumulating, so the stock must be worth chasing. Most retail investors read that alert exactly wrong. Understanding block deal vs bulk deal is one of those small pieces of market literacy that quietly separates people who react to headlines from people who read what the exchange is actually disclosing. Both are official NSE and BSE disclosures, both involve large trades, and beyond that almost nothing about them is the same — not the trigger, not the trading window, not the price rules, and definitely not what they signal.

Two different reports, two different triggers

Start with what they have in common, because it is short. Both bulk deals and block deals are large-trade disclosures that the stock exchanges publish so that the market can see sizeable transactions it would otherwise miss. That is where the similarity ends.

A bulk deal is defined by quantity: any client whose total buying or selling in a single stock crosses half a percent of that company's listed shares in a day. A block deal is defined by value and executed in a completely separate trading window reserved for very large, negotiated trades. One is a size threshold that a trade can cross almost by accident during normal hours; the other is a deliberate, pre-arranged transaction routed through a special session.

Confusing the two leads to bad conclusions, because they carry very different information. A bulk deal can be a day-trader churning a mid-cap; a block deal is usually an institution moving a genuine position. If you want to build this kind of market-reading foundation properly rather than piecing it together from scattered videos, a structured stock market training course compresses years of trial and error into a few focused weeks.

What counts as a bulk deal (the 0.5% rule)

The rule is purely about proportion. When all of a single client's trades in one scrip on one exchange add up to more than 0.5% of the number of that company's equity shares listed on the exchange, that client's activity qualifies as a bulk deal. The 0.5% can be hit in one large order or across many smaller orders through the day — the exchange totals them up per client.

Three features matter for how you read it:

• No rupee minimum. A bulk deal is triggered by the quantity crossing 0.5%, irrespective of the trade's value. In a small-cap with few listed shares, even a modest rupee amount can cross the line.
• Normal market window. Bulk deals happen in the regular trading session, at prevailing market prices, alongside everyone else's orders. There is no special window.
• Same-day disclosure. The broker executing the trade reports it to the exchange, which publishes the bulk-deal list — client name, quantity, and weighted-average price — after the market closes that same day.

A quick illustration makes the proportional nature clear. Suppose a company has 10 crore equity shares listed. Half a percent of that is 5 lakh shares, so any client whose net buying or selling in that stock touches 5 lakh shares in a day gets reported as a bulk deal. Now take a company with only 1 crore listed shares: the same rule triggers at just 50,000 shares. The threshold scales with the company's size, which is why the same rupee amount can be a bulk deal in one stock and a routine trade in another.

Because the threshold is proportional, bulk-deal lists on NSE and BSE are dominated by mid-caps and small-caps, where 0.5% of the float is a reachable number. In a heavyweight like an index major, crossing 0.5% in a day takes an enormous order, so genuine large-caps appear far less often. That size bias is worth remembering: the stocks that show up most often on these lists are precisely the ones where a single active trader can tip the scale. We unpacked how sustained institutional buying and selling actually shows up in the tape in our guide to FII and DII data and institutional flows, which is a more reliable signal than any single day's bulk print.

What counts as a block deal (the separate window)

A block deal is a large, negotiated trade executed in a dedicated block-deal window that runs outside the continuous market. It exists so that big buyers and sellers can transact large quantities at a mutually agreed price without their order visibly moving the market for hours. SEBI overhauled this framework through a circular dated 8 October 2025, with the revised rules taking effect on 7 December 2025 — so the numbers below are the current ones, and they are meaningfully different from the old regime many older articles still quote.

Under the current framework, a block deal must meet these conditions:

• Minimum order value of ₹25 crore, raised from the earlier ₹10 crore. This keeps the window for genuinely large trades.
• Price within ±3% of the reference price (the previous day's closing price), widened from the old ±1% band, which had made deals hard to execute.
• Two windows a day instead of one: a morning session from 8:45 to 9:00 and an afternoon session from 2:05 to 2:20.
• Mandatory delivery. Every block-window trade must result in actual delivery of shares, and client identities are disclosed — there is no squaring off inside the window.

The design intent is transparency with minimal disruption. A mutual fund rebalancing a large holding, a promoter selling a stake, or a private-equity investor exiting can move a very large block at a controlled price, and the market sees the disclosure rather than watching a giant order churn the order book. If you are still building intuition for how large orders interact with visible depth, our explainer on the bid-ask spread and reading the order book pairs naturally with this.

What SEBI's December 2025 revamp changed for block deals

Source: SEBI Review of Block Deal Framework circular, October 2025 (effective December 2025).

Block deal vs bulk deal at a glance

When you line the two disclosures up side by side, the difference in what they can tell you becomes obvious. A bulk deal is a proportional threshold crossed in the open market; a block deal is a large negotiated trade in a walled-off window. Use this comparison as your quick reference the next time either term flashes past.

Source: SEBI and NSE trading framework; block-deal figures per the December 2025 rules.

What these disclosures do NOT tell you

This is where most retail readers go wrong. A bulk-deal print is not, on its own, evidence that a smart investor is accumulating a stock. The 0.5% threshold counts net activity by a client in a day, and a very large share of bulk deals are simply intraday round trips — the same client buys and sells the same stock within the day, crossing the threshold in the process.

One independent analysis of roughly 90,000 NSE bulk-deal records found that close to 72% were same-day round trips rather than positions carried forward. Treat that figure as illustrative rather than official, but the direction is the useful lesson: a name on the bulk-deal list often reflects churn, not a long-term bet. Chasing a stock because it appeared on that list is reacting to noise.

A few more cautions worth internalising:

• A block deal is not an endorsement. A large negotiated sale can be an investor rebalancing or exiting for reasons that have nothing to do with your thesis. Disclosure tells you a trade happened, not why.
• Neither is a tip. Seeing an institution's name against a purchase is not a recommendation to buy; you do not know their entry cost, time horizon, or hedges.
• Surveillance still applies. Stocks that see unusual activity can move into monitoring frameworks that restrict trading, which we covered in our post on the ASM and GSM surveillance framework on NSE.

Used well, these lists are a starting point for questions — who traded, how much, at what price — not an answer key.

Where to read them and what to do next

Both NSE and BSE publish their bulk-deal and block-deal reports on their own websites after market hours every trading day. On NSE, look for the Bulk Deals and Block Deals reports under the market-data section; BSE carries the equivalent pages. Note that a bulk deal you see in the special block window is a different disclosure from the intraday block trading session mechanics — the report is the data, the session is the plumbing that produced it.

The practical habit is simple: when a bulk or block deal catches your eye, read it as one data point among many. Cross-check it against fundamentals, delivery volumes, and broader institutional flows before you form any view. That discipline — treating disclosures as inputs, not signals — is exactly what structured market education is meant to build.

Frequently Asked Questions

Is a bulk deal good or bad for a stock?

Neither by itself. A bulk deal only tells you that one client's trading in a stock crossed 0.5% of its listed shares in a day. A large part of bulk-deal activity is intraday churn, so it is not evidence of long-term accumulation. Read it alongside fundamentals and delivery data rather than as a buy or sell cue.

Where can I see block deals and bulk deals?

NSE and BSE both publish bulk-deal and block-deal reports on their official websites after the market closes each trading day. The reports list the client name, the stock, the quantity, and the weighted-average or traded price, so you can see exactly what was disclosed.

What is the minimum value for a block deal in India?

Under SEBI's framework effective December 2025, a block deal requires a minimum order value of ₹25 crore, up from the earlier ₹10 crore. Trades must also be within ±3% of the previous day's closing price and are executed in a dedicated block-deal window.

Can a retail investor do a block deal?

In practice, no. The ₹25 crore minimum order value puts block deals well beyond ordinary retail sizes, so the window is used by institutions, promoters, and other large participants. Retail investors trade in the normal market window at prevailing prices.

What is the difference between a block deal and a bulk deal in one line?

A bulk deal is any client crossing 0.5% of a company's listed shares in the normal market in a day; a block deal is a large trade of at least ₹25 crore executed in a separate negotiated window within ±3% of the previous close.

Disclaimer: This article is for educational purposes only and does not constitute investment advice. Markets carry risk — please do your own research or consult a qualified financial professional before investing. NIFM provides training and exam preparation; certification exams conducted by regulatory or professional bodies are administered by those bodies independently.