SEBI T+0 settlement expanded to top 500 stocks: liquidity profile, optional vs default toggle, and broker readiness

Indian cash equity shifted from T+2 to a rolling T+1 cycle on 27-Jan-2023, cutting counterparty exposure by a full trading day. The next leap is T+0, where the buy and sell legs of the same trade settle the same evening. SEBI's circular dated 21-Dec-2024 announced the phased expansion of optional T+0 settlement to the top 500 stocks by market capitalisation, building on the 28-Mar-2024 beta that launched with 25 scrips. This pre-open note maps the new liquidity surface, the optional toggle that lets clients choose T+0 over T+1 till 1:30 PM IST, and what brokers still need to wire before the August 2024 FPI inclusion translates into actual cross-border same-day flows.

The immediate read-through is that retail traders running systematic investment plans or one-off lumpsum allocations will see no operational change because the broker handles the channel selection. The change matters at the margin for self-directed clients moving large lots intraday, for treasurers parking surplus, and for mutual fund schemes managing redemption-heavy days.

Market Snapshot

The settlement cycle is itself the headline today. Before 28-Mar-2024 every cash leg cleared on a T+1 timetable; on that date the Securities and Exchange Board of India launched the optional T+0 beta with 25 scrips listed on both BSE and NSE. Following the 21-Dec-2024 press release the eligible universe is being broadened in tranches of 100 stocks ranked by market capitalisation, so that ranks 101-500 progressively join the existing top 100 to reach a 500-stock universe.

Two structural caveats define the snapshot. First, the optional T+0 window closes at 1:30 PM IST: trades placed after that timestamp on an eligible scrip continue to settle on the T+1 cycle. Second, block deals and the pre-open session continue at T+1, because the price discovery there is structurally different from continuous trading. Retail traders confused by the channel split should re-read the rules for block deals versus bulk deals before assuming that a large order qualifies for same-day funds release.

What Moved Yesterday

Yesterday's headline read-through is structural rather than tick-level. Once ranks 101-500 by market cap enter the T+0 tape, the depth profile of mid-caps changes: a mid-cap that earlier required 24 hours of margin park can now release capital the same evening for clients opting into T+0. SEBI's 21-Dec-2024 circular makes the broker opt-in mandatory for the channel itself and the client opt-in voluntary at the order level, which means the actual fraction of the order book settling T+0 will depend on how many qualified clearing members switch on the workflow.

The other quiet move was the eligibility of mutual funds. Vide circular SEBI/HO/IMD/IMD-SEC1/P/CIR/2024, asset management companies are now permitted to use T+0 for portfolio liquidity management. This matters because in a redemption-heavy day a scheme earlier had to plan for T+1 settlement to meet next-day pay-out; T+0 collapses that into the same evening for trades booked before 1:30 PM IST. Foreign portfolio investors were enabled through SEBI's August 2024 consultation paper, so the foreign side of the order book is no longer a structural blocker on the regulatory side.

Internal short-selling rules did not move. The intraday short-selling restrictions that apply on the T+1 cash tape continue to apply on the T+0 cash tape, so a client cannot exploit the cycle to evade the square-off discipline that already exists in cash equity. Likewise, the differential price between the T+0 and T+1 legs of the same scrip is expected to converge to T+1 once participation scales, because the absence of arbitrage forces convergence after initial discovery.

What to Watch Today

Watch three buckets at the open.

First, the spread between the T+0 and T+1 prices for the same scrip. In the 28-Mar-2024 beta SEBI flagged that a small differential price could emerge during initial discovery; the 21-Dec-2024 circular reiterates that this differential should converge to T+1 over time as the optional channel scales. Today is a useful day to log the basis on the 25 original beta scrips against the ranks 101-500 entrants to confirm whether convergence has held since the December 2024 announcement.

Second, broker readiness. Eligible brokers must opt-in, and several mid-sized members may take more than one settlement cycle to enable the workflow because their back-office funds pay-in routine needs to compress to a same-day timetable. A client who places an order at 1:25 PM IST expecting T+0 but whose broker has not yet opted in will see the trade default to T+1, with no error message at the terminal.

Third, the August 2024 FPI inclusion route. Foreign portfolio investors hold custody arrangements that were built for a T+1 funding window. The compression to T+0 has knock-on effects on custodian SWIFT cut-offs and FX conversion timestamps, which means the first FPI-driven T+0 trades will signal whether the custody plumbing is ready. SEBI's consultation paper of August 2024 cleared the regulatory side; the operational side is still being wired by individual custodians.

Practical Takeaways

For a retail investor running a systematic plan, the new settlement cycle is largely invisible: a fixed-date SIP mandate or a step-up SIP debits on schedule and the broker's mutual fund or equity leg clears through the normal pipeline. The cycle change matters at the margin for self-directed clients moving large lots intraday, because a sell at 12:00 PM IST under T+0 releases funds the same evening for a buy at 3:00 PM IST, halving the lag relative to T+1.

For corporate treasurers parking surplus in liquid equity proxies, the optional T+0 toggle reduces the working capital tied up in clearing margin. The Securities and Exchange Board of India retains the right to suspend the channel scrip by scrip on surveillance grounds, so this is not a stable property of every eligible name -- it is a daily, scrip-level toggle that the exchange can switch off.

For mutual fund unit-holders, the practical effect is on liquidity. A scheme that earlier sized its cash buffer for T+1 redemption settlement can shave that buffer using the SEBI/HO/IMD/IMD-SEC1/P/CIR/2024 permission, which over time may translate into a tighter tracking error for index funds because less drag-cash is parked uninvested through the settlement window.

For active intraday traders, the cycle interacts with margin. Capital released on a T+0 sell can be redeployed the same evening, but the order has to be booked before 1:30 PM IST, and the broker must have flagged the channel as live for that client on that scrip. The toggle is not a property of the scrip alone; it is the intersection of scrip eligibility, broker enrolment and client opt-in.

FAQ

What is the deadline for placing a T+0 trade on an eligible scrip?

1:30 PM IST. SEBI's circular dated 21-Dec-2024 fixes 1:30 PM IST as the cut-off for the optional T+0 settlement window. Trades booked after 1:30 PM IST on the same eligible scrip continue to settle on the T+1 cycle, with no override available at the terminal level.

Which 500 stocks are eligible for T+0 settlement?

The top 500 listed companies ranked by market capitalisation. The earlier 28-Mar-2024 beta enabled 25 scrips; the 21-Dec-2024 circular extends eligibility to the top 100 first and then to ranks 101-500 in tranches, with the end-state being the top 500 by market cap measured on the SEBI-published reference dates.

Is T+0 settlement compulsory for the eligible 500 stocks?

No. The 21-Dec-2024 SEBI circular makes broker opt-in mandatory for the channel but client opt-in voluntary at the order level. A client can continue to trade on the T+1 cycle even on an eligible scrip, and a broker that has not opted in cannot route a client into the T+0 channel.

Can FPIs use T+0 settlement?

Yes. SEBI's consultation paper of August 2024 enabled the FPI route to participate in the T+0 segment. Actual flow depends on custodian readiness because the FX conversion and SWIFT funding cut-offs were originally built around a T+1 settlement window, and individual custodians are upgrading these workflows over the rollout.

Do block deals and pre-open trades clear at T+0?

No. The 21-Dec-2024 SEBI circular specifies that block deals and the pre-open session continue to clear at T+1 because their price discovery is structurally different from continuous trading, and the differential price risk in those windows is judged unsuitable for same-day settlement.

Are mutual funds permitted to use T+0?

Yes. SEBI permits asset management companies to use the optional T+0 channel for portfolio liquidity management, vide circular SEBI/HO/IMD/IMD-SEC1/P/CIR/2024. This is helpful for redemption-heavy days because the scheme can release equity legs the same evening rather than waiting for the T+1 cycle.

Does T+0 change intraday short-selling rules?

No. The intraday short-selling restrictions that apply on the T+1 cash tape continue to apply on the T+0 cash tape, per the 21-Dec-2024 SEBI circular. A client cannot use the optional shorter cycle to evade the square-off discipline that already governs cash equity short positions.