1

ATO/ ATC Orders

Priority Adjustment: ATO/ATC orders are no longer prioritized over existing limit orders (LO).

Illustration

Price Display: ATO/ATC prices are no longer shown on the price board. Instead, the limit price is displayed, providing clearer visibility of executable prices.

Illustration

Volume Information: The pending order board will reflect a reduced executable volume. Bid/ask volumes at the top 03 price levels will show the estimated remaining volume after matching.

Details in Section 1: Interpretation 

Implication: 

• Investors may need additional data to estimate matched volumes during opening and closing call auctions. This information is available on HSC ONE.
• As ATO/ATC orders lose priority, execution at desired prices may be less certain, particularly in volatile sessions. Consider using ceiling (buy) or floor (sell) limit orders for better control.

ATO/ATC orders are prioritized over limit orders. 

"ATO"/"ATC" prices are displayed on the price board.

2

Amend/ Cancel Orders

Price and volume cannot be amended simultaneously. 

Priority rules: 

a) Amending price or increasing volume alters time priority. 

b) Decreasing volume retains time priority. 

Amendment/cancellation rules: 

• Opening/Closing Periodic Call Auction: No change. 
• During the last five minutes of Periodic Call Auctions (PCA) for securities under trading restrictions, amendments and cancellations are not allowed. 

Implication: 

• Investors must take 02 separate actions to amend both price and volume. 
• Amending price or increasing volume affects order priority; investors may consider placing new orders for additional volume.

HOSE: Cannot amend volume. 

HNX: Can amend both price and volume.

3

Trading boards & Trading sessions

Divide into 07 boards.

Trading hours and order types differ across Exchanges.

Illustration

4

Put-through Orders

Change of trading hours:

• Main trading session: 09:00-14:45
• Post-market trading session: 14:45-15:00

Both buyer and seller can initiate orders; the counterparty may accept or reject. 

Amendment: Executed put-through transactions cannot be canceled. 

Implication: 

• Main and post-market sessions operate on separate boards, requiring unmatched orders from the main session to be re-entered in the post-market session. 
• Unmatched put-through orders in the main session must be reordered in the post-market session.  

Valid throughout full session (09:00–15:00).

Seller enters order; buyer confirms. 

Amendments allowed per regulations.

5

Foreign investor trading

Current room updates: The bid volume of stocks and fund certificates is immediately deducted from the current room once an order is entered into the system.

• Regular Transactions:
  • Bid volume is deducted from the current room upon order entry
  • Decreasing bid volume increases the room. If the available room is insufficient, the order will be rejected. 
  • Cancelled or expired orders restore the room.
• Put-through Transactions: 
  • When a foreign investor buys from a domestic seller, the current room decreases upon order entry.
  • If the foreign buyer cancels or the domestic seller rejects the order, the current room is restored.

1

Contract Code

Futures contract codes now follow the ISIN-standard format:

• Format: [futures type] _ [futures group] _ [basic stock code] _ [expiry year] _ [expiry month] _ [futures code] 
• Example: 41I1F7000 = [4] _ [1] _ [l1] _ [F] _ [7] _ [000] 

(ISIN : International Securities Identification Number)

Implication:

• Future contract codes listed before go-live remain unchanged.
• Future contract codes listed after go-live follow new ISIN structure.
• Platforms like WinnerTrade and HSC ONE will show full future contract names to support investor trading.

Future Contract code consists of 3 components: Underlying Asset - Contract Type - Expiry.

2

MTL Orders

If not fully matched, the remaining volume of MTL is converted into a limit order (LO): 

• For buy orders: at the last matched price + 1 tick size 
• For sell orders: at the last matched price – 1 tick size

The remaining part of unmatched MTL Order is converted into LO order with order price defined be the last price.

3

Amend/ Cancel Orders

Price and volume cannot be amended simultaneously. 

4

ATO/ATC Orders

• No priority over ceiling/floor limit orders.
• Limit prices are displayed instead of “ATO”/“ATC” indicators.
• Volume at the top 03 bid/ask levels reflects post-matching estimates. 

ATO/ATC orders are prioritized. 

"ATO"/"ATC" prices shown on price board.

5

Buying power

Buying power updates immediately upon deposit.

6

Futures fees

Overnight Position Management Fee discontinued. 

Replaced with Derivatives Clearing Fee: 2,550 VND/contract 

Illustration

Implication: 

• Investors holding positions overnight no longer pay the Overnight Position Management Fee but will pay the Clearing Fee per transaction. 
• Intraday investors incur additional fees compared to the previous system.

Overnight Position Management Fee is 2,550 VND/contract/account/day.