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POST
/
margin
/
orders
/
{order_id}
/
amend
Amend Order
curl --request POST \
  --url https://external-api.kalshi.com/trade-api/v2/margin/orders/{order_id}/amend \
  --header 'Content-Type: application/json' \
  --header 'KALSHI-ACCESS-KEY: <api-key>' \
  --header 'KALSHI-ACCESS-SIGNATURE: <api-key>' \
  --header 'KALSHI-ACCESS-TIMESTAMP: <api-key>' \
  --data '
{
  "ticker": "<string>",
  "price": "0.5600",
  "count": "10.00",
  "client_order_id": "<string>",
  "updated_client_order_id": "<string>"
}
'
{
  "order_id": "<string>",
  "client_order_id": "<string>",
  "remaining_count": "10.00",
  "fill_count": "10.00",
  "average_fill_price": "0.5600",
  "average_fee_paid": "0.5600"
}

Documentation Index

Fetch the complete documentation index at: https://docs.kalshi.com/llms.txt

Use this file to discover all available pages before exploring further.

Amending a resting order preserves queue position only when the amendment decreases size. All other amendments — like increasing size or changing price forfeit queue position and place the order at the back of the queue.

Authorizations

​
KALSHI-ACCESS-KEY
string
header
required

Your API key ID

​
KALSHI-ACCESS-SIGNATURE
string
header
required

RSA-PSS signature of the request

​
KALSHI-ACCESS-TIMESTAMP
string
header
required

Request timestamp in milliseconds

Path Parameters

​
order_id
string
required

Order ID

Query Parameters

​
subaccount
integer
default:0

Subaccount number (0 for primary, 1-32 for subaccounts). Defaults to 0.

Required range: x >= 0

Body

application/json
​
ticker
string
required

Market ticker

​
side
enum<string>
required

Side of the order

Available options:
bid,
ask
​
price
string
required

Updated price for the order in fixed-point dollars.

Example:

"0.5600"

​
count
string
required

String representation of the updated quantity for the order.

Example:

"10.00"

​
client_order_id
string

The original client-specified order ID to be amended

​
updated_client_order_id
string

The new client-specified order ID after amendment

Response

Order amended successfully

​
order_id
string
required
​
client_order_id
string
​
remaining_count
string | null

Number of contracts remaining after the amend. Only present when the amend caused a fill or changed the resting size.

Example:

"10.00"

​
fill_count
string | null

Number of contracts filled as a result of the amend crossing the book. Only present when fills occurred or remaining size changed.

Example:

"10.00"

​
average_fill_price
string | null

Volume-weighted average fill price for fills resulting from the amend. Only present when fills occurred.

Example:

"0.5600"

​
average_fee_paid
string | null

Volume-weighted average fee paid per contract for fills resulting from the amend. Only present when fills occurred.

Example:

"0.5600"