Bulk deals vs block deals: what the difference means (2026)

Bulk deals vs block deals is the first distinction to get right when reading large trades on Indian exchanges. Both tell you that a big buyer or seller was active in a stock on a given day, but they run under different rules, trade in different places, and are triggered by different tests. Read on 18 September 2026, the current rules are these: a bulk deal is any trade above 0.5 percent of a company's listed shares in the normal market, under SEBI's circular of 14 January 2004; a block deal is a single trade of at least 25 crore rupees in a separate window, under SEBI's circular of 8 October 2025, which took effect on the 60th day after issue. Knowing which one you are looking at is the difference between reading the data right and misreading it.

What are bulk deals vs block deals, in one line each?

A bulk deal is triggered by size, not by a special window. When the total quantity a single client buys or sells in a stock crosses 0.5 percent of that company's listed equity shares in one trading day, the broker has to report it to the exchange, which publishes it after market hours. Bulk deals happen in the normal trading session, and the quantity can build up across the day before it crosses the threshold. Source: SEBI circular SEBI/MRD/SE/Cir-7/2004 dated 14 January 2004, as reproduced in SEBI press release 112/2005.

A block deal is defined by value and executed in a separate space. Two parties agree a large trade in advance and put it through a dedicated block deal window rather than the open market, so it does not move the regular order book. SEBI's circular of 8 October 2025 describes it as the "execution of large trades through a single transaction without putting either the buyer or seller in a disadvantageous position", and sets the minimum order size at 25 crore rupees.

How do the two block deal windows price a trade?

The 8 October 2025 circular replaced the earlier framework with two windows, each with its own reference price:

• Morning window, 08:45 to 09:00. The reference price is the previous day's closing price of the stock (paragraph 2.2.1.1).
• Afternoon window, 14:05 to 14:20. The reference price is the volume weighted average price (VWAP) of cash-market trades in the stock between 13:45 and 14:00. Between 14:00 and 14:05 the exchanges calculate and publish that VWAP so both sides know the number before the window opens (paragraph 2.2.1.2).

In either window, orders must sit within 3 percent of the applicable reference price, subject to surveillance measures and the stock's price bands (paragraph 2.2.2). Every block trade must result in delivery: it cannot be squared off or reversed (paragraph 2.2.3). The same conditions apply to the block deal window under the optional T+0 settlement cycle (paragraph 2.2.5).

Bulk deals vs block deals at a glance

For a column-by-column walk through an actual exchange record, see how to read a block deal disclosure. For the daily routine of pulling both feeds, see how to track bulk and block deals.

How to read the data without over-reading it

A bulk or block deal is a record of one day's activity, so read it with its limits in mind.

• The trade is a fact; the motive is not. A large sale can be portfolio rebalancing, a fund redemption, or a promoter raising cash. The disclosure does not say which.
• Thresholds and windows change. The October 2025 circular replaced the block deal framework in SEBI's master circular for stock exchanges, so check the rule in force on the date of the trade you are reading rather than assuming today's minimum applied.
• A block deal is not a bulk deal, and one trade can be reported as both. A block window trade that also crosses 0.5 percent of listed shares can appear in both feeds; count the shares once.
• Watch for repeated activity in the same name across days, or the same buyer turning up in several names. That is the pattern behind smart money convergence, and it is verifiable from the public record.

Where does bulk deals vs block deals data live?

The NSE and BSE each publish the day's bulk deals and block deals on their websites after the close, and the NSE's bulk deal file covers the current day only, so anything older has to come from an archive. Flock ingests both exchanges' deal reports daily, stamps each row with its date, and links it back to the exchange record; a bulk deals tracker or block deal alerts sits on top of that same feed. The trade is public. What it means for you is your call to make.