Order Entry Messages

Overview

Kalshi treats all orders as bids or asks for Yes contracts. Selling Yes is equivalent to buying No contracts.

New Order Single (35=D)

Used to submit a new order to the Exchange.

Tag	Name	Type	Required	Description
11	ClOrderID	String	Y	Client order identifier for idempotency. Must not match any open orders. UUID format is preferred. Validation: • Maximum 64 characters • Only alphanumeric, ”+”, ”=”, ”_”, ”-”, and ”:” characters allowed • Pattern: `^[\-\w:+=/]*$`
18	ExecInst	Char	N	Execution instruction flags. Supported values: 6 = Post Only
38	OrderQty	Integer	Y	Number of contracts to trade.
40	OrdType	Char	Y	Order type. Supported values: 2 = Limit
44	Price	Integer	Y	Price per contract in cents (1-99).
54	Side	Char	Y	Side of the order. Supported values: 1 = Buy (Yes contracts) 2 = Sell (No contracts)
55	Symbol	String	Y	Market ticker (e.g., “EURUSD-23JUN2618-B1.087”).
59	TimeInForce	Char	N	Specifies how long the order remains in effect. Supported values: 0 = Day (expires at 11:59:59.999pm ET) 1 = Good Till Cancel (GTC) 3 = Immediate Or Cancel (IOC) 4 = Fill Or Kill (FOK) 6 = Good Till Date (GTD) Note: Day orders expire at 11:59:59.999pm ET. For GTD orders, any date in the past is treated as Immediate Or Cancel.
126	ExpireTime	UTCTimestamp	C	Required when TimeInForce=GTD. Specifies when the GTD order expires.
448	PartyID	UUID	N	Only applicable for FCM entities . Sub-account identifier.
452	PartyRole	Integer	N	Only applicable for FCM entities . Party role. Supported values: 24 = Customer Account
453	NoPartyIDs	Integer	N	Only applicable for FCM entities . Number of parties. Currently, only 1 is supported.
526	SecondaryClOrdID	UUID	N	Order group identifier. Please refer to the Order Groups tab for more information.
2964	SelfTradePreventionType	Char	N	Self-trade prevention mode. If unset, defaults to Taker At Cross. Supported values: 1 = Taker At Cross 2 = Maker
21006	CancelOrderOnPause	Boolean	N	If this flag is set to true, the order will be canceled if the order is open and trading on the exchange is paused for any reason.

8=FIXT.1.1|9=200|35=D|34=5|52=20230809-12:34:56.789|49=your-api-key|56=KalshiNR|
11=550e8400-e29b-41d4-a716-446655440000|38=10|40=2|54=1|55=HIGHNY-23DEC31|44=75|
59=1|10=123|

Order Cancel/Replace Request (35=G)

Used to modify an existing order without canceling it.

Supported Modifications

OrderQty: Increases or decreases the quantity of your order, note that increasing the quantity for the same point means forfeiting your queue position
Price: Changes the limit price of your order

Tag	Name	Type	Required	Description
11	ClOrderID	String	Y	Unique modification request identifier. Must not match any existing ClOrderID. UUID format is preferred. Validation: • Maximum 64 characters • Only alphanumeric, ”+”, ”=”, ”_”, ”-”, and ”:” characters allowed • Pattern: `^[\-\w:+=/]*$`
37	OrderID	String	N	Order identifier provided by Kalshi Exchange.
38	OrderQty	Integer	Y	New total quantity for the order. Note: If OrderQty equals filled quantity, the order will be canceled. If less than filled quantity, the request will be rejected.
40	OrdType	Char	Y	Order type. Supported values: 2 = Limit
41	OrigClOrdID	String	Y	ClOrderID of the order to modify.
44	Price	Integer	N	New price per contract in cents (1-99). Required if changing price.
54	Side	Char	Y	Must match the original order side.
55	Symbol	String	Y	Must match the original order symbol.
448	PartyID	UUID	N	Only applicable for FCM entities . Sub-account identifier. Must match the original order field value.
452	PartyRole	Integer	N	Only applicable for FCM entities . Party role. Must match the original order field value. Supported values: 24 = Customer Account
453	NoPartyIDs	Integer	N	Only applicable for FCM entities . Number of parties. Must match the original order field value. Currently, only 1 is supported.

Order Cancel Request (35=F)

Cancel all remaining quantity of an existing order.

Tag	Name	Type	Required	Description
11	ClOrderID	String	Y	Unique cancel request identifier. Must not match any existing ClOrderID. UUID format is preferred. Validation: • Maximum 64 characters • Only alphanumeric, ”+”, ”=”, ”_”, ”-”, and ”:” characters allowed • Pattern: `^[\-\w:+=/]*$`
37	OrderID	String	N	Order identifier provided by Kalshi Exchange.
41	OrigClOrdID	String	Y	ClOrderID of the order to cancel.
54	Side	Char	Y	Must match the original order side.
55	Symbol	String	Y	Must match the original order symbol.
448	PartyID	UUID	N	Only applicable for FCM entities . Sub-account identifier. Must match the original order field value.
452	PartyRole	Integer	N	Only applicable for FCM entities . Party role. Must match the original order field value. Supported values: 24 = Customer Account
453	NoPartyIDs	Integer	N	Only applicable for FCM entities . Number of parties. Must match the original order field value. Currently, only 1 is supported.

Execution Report (35=8)

This message is sent by Kalshi Exchange back to clients to reflect changes to an order’s state (accepted, replaced, partially filled, filled or canceled).

Tag	Name	Type	Required	Description
6	AvgPx	Decimal	Y	Calculated average price of all fills on this order.
11	ClOrderID	String	Y	ClOrderID provided by the initiator on the last message that made any change to the order.
14	CumQty	Integer	Y	Total number of contracts filled in this order so far.
17	ExecID	String	Y	Unique sequenced identifier for this report message. Format: `integer;integer` pattern (e.g., “4;4”, “4;7”, “7;3”) Monotonically increasing at the Exchange level. Returns “-1;-1” for PENDING execution reports.
31	LastPx	Integer	C	Price of this (last) fill in cents. Present only for trade execution reports.
32	LastQty	Integer	C	Number of contracts bought or sold in this fill. Present only for trade execution reports.
37	OrderID	String	Y	Unique identifier for the order in the Kalshi Exchange. Use this ID when referencing the order for support.
38	OrderQty	Integer	Y	Total number of contracts currently in the order. OrderQty = CumQty + LeavesQty.
39	OrdStatus	Char	Y	Current status of the order after this event. See Order Status values below.
41	OrigClOrdID	String	C	ClOrderID of the previous non-rejected order state. Present for Replaced/Canceled orders.
44	Price	Integer	C	Price per contract in cents.
54	Side	Char	Y	Side of the original order. Values: 1 = Buy (Yes contracts) 2 = Sell (No contracts)
55	Symbol	String	Y	Market ticker for the order.
58	Text	String	N	Human-readable description of the execution report result.
60	TransactTime	UTCTimestamp	Y	Timestamp for the event that triggered this execution report.
103	OrdRejReason	Integer	C	Rejection reason. Present only when ExecType = Rejected. See Order Rejection Reasons below.
126	ExpireTime	UTCTimestamp	C	Order expiration timestamp. Returns 11:59pm ET for Day orders.
150	ExecType	Char	Y	Reason why this execution report was sent. See Execution Types below.
151	LeavesQty	Integer	Y	Remaining quantity open for further execution on this order.
448	PartyID	UUID	N	Only applicable for FCM entities . Sub-account identifier.
452	PartyRole	Integer	N	Only applicable for FCM entities . Party role. Supported values: 24 = Customer Account
453	NoPartyIDs	Integer	N	Only applicable for FCM entities . Number of parties. Currently, only 1 is supported.

Order Status (39)

New<0>: Active order, no fills
Partially Filled<1>: Some quantity filled
Filled<2>: Completely filled
Canceled<4>: Canceled (may have partial fills)
Pending Cancel<6>: Cancel pending
Rejected<8>: Order rejected
Pending New<A>: Order pending acceptance
Expired<C>: Time in force expired
Pending Replace<E>: Modification pending

Order Rejection Reasons (103)

Unknown symbol<1>
Exchange closed<2>
Order exceeds limit<3>
Too late to enter<4>
Duplicate order<6>
Unsupported order characteristic<11>
Unknown account<15>
Other<99>

Execution Types (150)

New<0>: Order accepted
Trade<F>: Order filled (partial or complete)
Canceled<4>: Order canceled
Replaced<5>: Order modified
Rejected<8>: Order rejected
Expired<C>: Order expired
Pending New<A>: Order pending acceptance
Pending Cancel<6>: Cancel pending
Pending Replace<E>: Modification pending

Text Field Values (58)

Common values for the Text field in Execution Reports:

EXCHANGE_UNAVAILABLE - Catch-all for Exchange outage or unmapped errors, maps to OrdRejReason “Other”
MARKET_ALREADY_CLOSED - maps to OrdRejReason “Exchange closed”
MARKET_INACTIVE - maps to OrdRejReason “Exchange closed”
MARKET_NOT_FOUND - maps to OrdRejReason “Unknown symbol”
SELF_CROSS_ATTEMPT - maps to ExecutionType “Canceled”
SELF_CROSS_ATTEMPT_PARTIALLY_FILLED - maps to ExecutionType “Canceled”
ORDER_ALREADY_EXISTS - maps to OrdRejReason “Duplicate order”
INVALID_AMEND_QTY_FOR_ORDER - maps to OrdRejReason “Other”
CANNOT_UPDATE_FILLED_ORDER - maps to OrdRejReason “Too late to enter”
EXCEEDED_ORDER_GROUP_RISK_LIMIT - maps to OrdRejReason “Order exceeds limit”
INSUFFICIENT_BALANCE - maps to OrdRejReason “Other”
EXCHANGE_PAUSED - maps to OrdRejReason “Exchange closed”
TRADING_PAUSED - maps to OrdRejReason “Exchange closed”
INVALID_ORDER - maps to OrdRejReason “Unsupported order characteristic”
ORDER_GROUP_NOT_FOUND - maps to OrdRejReason “Unsupported order characteristic”
EXCEEDED_PER_MARKET_RISK_LIMIT - maps to OrdRejReason “Order exceeds limit”
EXCEEDED_SELL_POSITION_FLOOR - maps to OrdRejReason “Order exceeds limit”
NOT_FOUND - maps to OrdRejReason “Unknown symbol”
CUSTOMER_ACCOUNT_NOT_FOUND - maps to OrdRejReason “Unknown account”
PERMISSION_DENIED_FOR_CUSTOMER_ACCOUNT - maps to OrdRejReason “Unknown account”
FOK_INSUFFICIENT_VOLUME - maps to ExecutionType “Canceled”
POST_ONLY_CROSS - maps to OrdRejReason “Other”
ORDER_GROUP_CANCEL - maps to ExecutionType “Canceled”
TAKER_CANCEL_FOR_SELF_TRADE_PREVENTION - maps to ExecutionType “Canceled”
MAKER_CANCEL_FOR_SELF_TRADE_PREVENTION - maps to ExecutionType “Canceled”
IMMEDIATE_OR_CANCELLED - maps to ExecutionType “Canceled”

Position and Fee Information

When ExecType=Trade:

Tag	Name	Description
704	LongQty	Net Yes position after trade
705	ShortQty	Net No position after trade
136	NoMiscFees	Number of fees
137	MiscFeeAmt	Total fees in dollars
138	MiscFeeCurr	Currency (USD)
139	MiscFeeType	Exchange Fees<4>
891	MiscFeeBasis	Fee unit (always ABSOLUTE<0>)
880	TrdMatchID	Unique trade identifier
1057	AggressorIndicator	Taker/Maker flag

Collateral Changes

Tag	Name	Description
1703	NoCollateralAmounts	Number of collateral changes
1704	CurrentCollateralAmount	Delta in dollars
1705	CollateralType	BALANCE or PAYOUT

Party Information

Party fields from the original order request are echoed back in ExecutionReports:

Tag	Name	Description
453	NoPartyIDs	Number of parties (for sub-accounts)
448	PartyID	Sub-account identifier
452	PartyRole	Customer Account<24>

Party fields are only included when the order is placed under a sub-account. These fields help track orders across different sub-accounts or FCM clients.

Rejection Reasons (102)

Too late to cancel<0>: Order already filled
Unknown order<1>: Order not found
Other<99>: See Text field

Mass Cancel Request (35=q)

Cancel all orders for the trading session.

Tag	Name	Description
11	ClOrderID	Unique request ID
530	MassCancelRequestType	Cancel for session<6>

Mass Cancel Report (35=r)

Response to mass cancel request.

Tag	Name	Description
11	ClOrderID	Request ID
37	OrderID	Operation ID
531	MassCancelResponse	Success<6> or Rejected<0>
532	MassCancelRejectReason	If rejected

Individual ExecutionReports will follow for each canceled order.

​Order Entry Messages

​Overview

​New Order Single (35=D)

​Order Cancel/Replace Request (35=G)

​Supported Modifications

​Order Cancel Request (35=F)

​Execution Report (35=8)

​Order Status (39)

​Order Rejection Reasons (103)

​Execution Types (150)

​Text Field Values (58)

​Position and Fee Information

​Collateral Changes

​Party Information

​Rejection Reasons (102)

​Mass Cancel Request (35=q)

​Mass Cancel Report (35=r)

Order Entry Messages

Overview

New Order Single (35=D)

Order Cancel/Replace Request (35=G)

Supported Modifications

Order Cancel Request (35=F)

Execution Report (35=8)

Order Status (39)

Order Rejection Reasons (103)

Execution Types (150)

Text Field Values (58)

Position and Fee Information

Collateral Changes

Party Information

Rejection Reasons (102)

Mass Cancel Request (35=q)

Mass Cancel Report (35=r)