Place Order

/sapi/v1/trade/order

Request type: POST

Signature verification: Yes

Interface permission: Trade

Rate Limit: Generally, the private interface rate limit of API key is at most 144 times every 3 seconds for each UID (Trade Interface: at most 72 times every 3 seconds. Read Interface: at most 72 times every 3 seconds) (this rate limit is shared by all the altcoins contracts delivered by different date).

Interface description: Place an order in futures trading.

Request Address

Environment	Address
Online	https://api.sunx.io
Online (preferred by aws customers)	https://api.sunx.io

Request Parameter

Parameter	Data Type	Required	Description	Value Range	Default Value
contract_code	String	true	Symbol
margin_mode	String	true	Margin mode: cross (Cross margin
position_side	String	false	Position side	long: going long; short: going short; both: One-way mode. You must input long or short and both is default.
side	String	true	Order side	buy; sell
type	String	true	Order type; enumeration	"market": market order; "limit": limit order; "post_only": post-only order
price_match	String	false	BBO and price are mutually exclusive	opponent: counterparty price; "optimal_5": Best 5 BBO; "optimal_10": Best 10 BBO; "optimal_20": Best 20 BBO
client_order_id	String	false	Order ID you entered	Clients fill and maintain themselves. the value must be in [1, 9223372036854775807]
price	String	false	Price, applicable for limit orders only. No price input is required for market orders.
volume	String	true	Order size, specifically in Cont
reduce_only	Integer	false	Reduce only: 0 is false; 1 is true
time_in_force	String	false	Enumerate FOK, IOC, and GTC. It is an optional field with GTC by default.
tp_trigger_price	String	false	Trigger price of your take profit order
tp_order_price	String	false	Price of your take profit order. (There is no need to input a price when using BBO.)
tp_type	String	false	Type of your take profit order. "market" is default with no input. "market": market order; "limit": limit order. "optimal_5": Best 5 BBO; "optimal_10": Best 10 BBO; "optimal_20": Best 20 BBO.
tp_trigger_price_type	String	false	Trigger price type of your take profit order. The last price is default.	"last": last price; "market": mark price
sl_trigger_price	String	false	SL Trigger Price
sl_order_price	String	false	Price of your stop loss order. (There is no need to input a price when using BBO.)
sl_type	String	false	Type of your stop loss order. "market" is default with no input. "market": market order; "limit": limit order. "optimal_5": Best 5 BBO; "optimal_10": Best 10 BBO; "optimal_20": Best 20 BBO.
sl_trigger_price_type	String	false	Trigger price type of your stop loss order. The last price is default.	"last": last price; "market": mark price
price_protect	boolean	false	Price protection. "false" is default. The parameter is needed when you set TP/SL.	false or true
self_match_prevent	String	false	Self-trading prevention	cancel_taker: Cancel a taker order cancel_maker: Cancel a maker order cancel_both: Cancel all orders	The default is cancel_taker

Response Parameter

Parameter	Data Type	Required	Description	Value Range
order_id	String	true	Order ID
client_order_id	String	false	The order ID you entered when placing an order. The ID will not be returned if it is not provided.

Notes: Remark: position_side is the side of your position. This parameter is optional in the One-way mode. The field is optional, and only "both" can be entered. However, in Hedge mode, this field is mandatory, and only "long" or "short" can be selected. In Hedge mode, "side" and "position_side" need to be combined. Open long (Enter "buy" in the side field; "long" in the position_side field) Open short (Enter "sell" in the side field; "short" in the position_side field) Close long (Enter "sell" in the side field; "long" in the position_side field) Close short (Enter "buy" in the side field; "short" in the position_side field) In One-way mode, a long position returns "buy," while a short position returns "sell."

Request Example

POST https://api.sunx.io/sapi/v1/trade/order?SignatureVersion=2&SignatureVersion=2&AccessKeyId=<your key>&Signature=<your signature>&SignatureMethod=HmacSHA256&Timestamp=2025-09-16T07%3A16%3A15

{
    "time_in_force": "gtc",
    "price_protect": "true",
    "contract_code": "BTC-USDT",
    "margin_mode": "cross",
    "position_side": "both",
    "price": 0.015,
    "volume": 2,
    "side": "buy",
    "type": "limit"
}

Response Example

{
    "code": 200,
    "data": {
        "client_order_id": "1329503956647878656",
        "order_id": "1329503956647878656"
    },
    "message": "Success",
    "ts": 1737020044270
}