The Singapore Stock Exchange is the primary exchange in Singapore.
Currency: Singapore Dollar (SGD)
Order Types
- Limit Buy/Sell→ShortSell (Day/IOC)
- Market Buy/Sell→ShortSell (Day/IOC)
Basic Market Rules
- Lot Size: 100 shares.
- Tick Size: defined by product type and price. The tick size for equities is listed in the following table.
| Price Range (SGD) | Tick Size (SGD) |
|---|---|
| Below 0.20 | 0.001 |
| 0.20 to below 1.00 | 0.005 |
| 1.00 to below 2.00 | 0.005 |
| 2.00 to below 10.00 | 0.01 |
| 10 and above | 0.01 |
- Short Sale Rules: short sell orders must be marked appropriately. For more information, see Chapter 8A of the Rulebooks.
- Circuit Breakers: for more information, you can see the Trading page.
Auction Mechanisms
The opening and closing market phases of the Singapore Stock Exchange are described in detail in Practice Note 8.2.1, which can be found under the SGX-ST Rules page.
Open
Orders can be entered from 08:30:00 to 08:59:00 (pre-open), followed by a non-cancellation period from 08:59:00 to 09:00:00, after which order matching will occur and the market will open.
- The Opening Routine is a 30-minute session before normal trading starts at 09:00 hours. It comprises the Pre-Open Phase and the Non-Cancel Phase.
- Pre-Open Phase (08:30 – 08:58-59)
- Orders can be entered, modified, or cancelled in the ready and unit share markets.
- The bid (offer) can be higher (lower) than the offer (bid).
- No matching of orders.
- This phase will end randomly at any time from 08:58 to 08:59 hours.
- Non-Cancel Phase (08:58 – 59 – 09:00)
- This phase will begin simultaneously with the end of the Pre-Open Phase, which may be at any time from 08:58 to 08:59 hours.
- No input, amendment, nor cancellation of orders.
- Orders that can be matched are matched at a single price computed based on an algorithm set by SGX-ST. The computed price will be the opening price for the day.
- Unmatched orders are carried forward into the morning trading session.
- This phase will begin simultaneously with the end of the Pre-Open Phase, which may be at any time from 08:58 to 08:59 hours.
Close
Orders that can be matched are matched at a single price computed based on an algorithm set by SGX-ST. The computed price will be the closing price for the day.
Note: The Flattening button does not work in the closing auction for this market. Instead, orders can be flattened only by manually sending a limit order that is not too aggressive, i.e., set close to the market price.
The methodology for computing the single price is as follows:
- a) A bid (offer) may be executed at a lower (higher) price.
- b) The cumulative bid (offer) volume at any price is the bid (offer) quantity at that price plus the sum of bid (offer) quantities at all higher (lower) prices.
- c) Sell (buy) pressure occurs when the cumulative offer (bid) volume is greater than the cumulative bid (offer) volume at a particular price. Zero pressure occurs when the cumulative offer volume is equal to the cumulative bid volume at a particular price.
- d) The tradable volume at any price is the lower of the cumulative bid or offer volume.
- e) The price overlap is the range of prices where tradable volumes are possible.
- f) The equilibrium is the price range within the price overlap where buy pressure changes to sell pressure. The computed price is either one of the following:
- i. The price within the equilibrium that has the largest trade volume, or
- ii. If there is no unique price, the average of all prices within the equilibrium with the maximum trade volume, or
- iii. The average is rounded to the next multiple of the minimum price multiple for this security or Futures Contract in the direction of the last traded price, or
- iv. If there is no last traded price, the average price is rounded to the next lower price multiple.
- g) If there is only buy or sell pressure within the price overlap, or if there is zero buy and sell pressure within the price overlap, or if the buy pressure and sell pressure are separated by a range of prices within the price overlap with zero pressure, the computing mechanism can be found in reference guide below
The methodology for computing the single price at which orders at the end of the Opening Routine, Closing Routine, and Adjust Phase are matched (“Equilibrium Price”) is as follows:
- The Equilibrium Price is the price that has the largest tradable volume and the lowest imbalance. “Imbalance” refers to the net difference between the cumulative bid volume and cumulative ask volume.
- If the highest tradable volume occurs at more than one price the Equilibrium Price is the price with the lowest imbalance.
- If the highest tradable volume and lowest imbalance occur at more than one price (“the price overlap”) the Equilibrium Price is determined by market pressure.
- If the highest tradable volume and lowest imbalance occur at more than one price and there is both buy and sell pressure or nil pressure within the price overlap, the Equilibrium Price is:
- the price within the price overlap that is the closest to the last traded price, or
- where there is no last traded price, the lowest price within the price overlap.
The Closing Range shall be the last 15 minutes of the Trading Phase, or such other time as may be determined by SGX-ST and notified to the market from time to time.
Unless otherwise specified, SGX-ST may use any of the following as the closing price of a Prescribed Security for a Trading Day:
- the single price at which orders are matched at the end of the Closing Routine;
- the last traded price that occurred in the Closing Range;
- a price determined by SGX-ST taking into account the bid and offer prices present in the Trading System during the Closing Range;
- the last traded price that occurred prior to the Closing Range; or
- the closing price of the previous Market Day.
Where SGX-ST deems it necessary or desirable for ensuring a fair, orderly, and transparent market or the integrity of the market, or for proper management of systemic risk in the market, SGX-ST may use an alternative formula and/or procedure to determine the closing price of a Prescribed Security.
Auction Periods
1. Pre-Close Phase (17:00 – 17:04-05)
All unmatched orders can be entered, reduced in quantity, or cancelled. No matching will take place.
2. Order Matching (17:04-05 – 17:06)
No order entry, amendment, or cancellation is allowed in this phase. All existing orders are matched at a single price according to the algorithm set by SGX-ST. All unmatched orders following the non-cancel phase at the close of trading will lapse. The computed single price will be the closing price of the day.
Auction Order Types: Limit order with TIF set as DAY.
For more information on the auction mechanisms on the Singapore Stock Exchange, see Practice Note 8.2.1.
