Amend Order (V2)
curl --request POST \
--url https://external-api.kalshi.com/trade-api/v2/portfolio/events/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": "HIGHNY-24JAN01-T60",
"side": "bid",
"price": "0.5700",
"count": "8.00",
"client_order_id": "8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1",
"updated_client_order_id": "2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a",
"exchange_index": 0
}
'import requests
url = "https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend"
payload = {
"ticker": "HIGHNY-24JAN01-T60",
"side": "bid",
"price": "0.5700",
"count": "8.00",
"client_order_id": "8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1",
"updated_client_order_id": "2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a",
"exchange_index": 0
}
headers = {
"KALSHI-ACCESS-KEY": "<api-key>",
"KALSHI-ACCESS-SIGNATURE": "<api-key>",
"KALSHI-ACCESS-TIMESTAMP": "<api-key>",
"Content-Type": "application/json"
}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {
'KALSHI-ACCESS-KEY': '<api-key>',
'KALSHI-ACCESS-SIGNATURE': '<api-key>',
'KALSHI-ACCESS-TIMESTAMP': '<api-key>',
'Content-Type': 'application/json'
},
body: JSON.stringify({
ticker: 'HIGHNY-24JAN01-T60',
side: 'bid',
price: '0.5700',
count: '8.00',
client_order_id: '8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1',
updated_client_order_id: '2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a',
exchange_index: 0
})
};
fetch('https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend', options)
.then(res => res.json())
.then(res => console.log(res))
.catch(err => console.error(err));<?php
$curl = curl_init();
curl_setopt_array($curl, [
CURLOPT_URL => "https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "POST",
CURLOPT_POSTFIELDS => json_encode([
'ticker' => 'HIGHNY-24JAN01-T60',
'side' => 'bid',
'price' => '0.5700',
'count' => '8.00',
'client_order_id' => '8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1',
'updated_client_order_id' => '2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a',
'exchange_index' => 0
]),
CURLOPT_HTTPHEADER => [
"Content-Type: application/json",
"KALSHI-ACCESS-KEY: <api-key>",
"KALSHI-ACCESS-SIGNATURE: <api-key>",
"KALSHI-ACCESS-TIMESTAMP: <api-key>"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"strings"
"net/http"
"io"
)
func main() {
url := "https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend"
payload := strings.NewReader("{\n \"ticker\": \"HIGHNY-24JAN01-T60\",\n \"side\": \"bid\",\n \"price\": \"0.5700\",\n \"count\": \"8.00\",\n \"client_order_id\": \"8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1\",\n \"updated_client_order_id\": \"2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a\",\n \"exchange_index\": 0\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("KALSHI-ACCESS-KEY", "<api-key>")
req.Header.Add("KALSHI-ACCESS-SIGNATURE", "<api-key>")
req.Header.Add("KALSHI-ACCESS-TIMESTAMP", "<api-key>")
req.Header.Add("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.post("https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend")
.header("KALSHI-ACCESS-KEY", "<api-key>")
.header("KALSHI-ACCESS-SIGNATURE", "<api-key>")
.header("KALSHI-ACCESS-TIMESTAMP", "<api-key>")
.header("Content-Type", "application/json")
.body("{\n \"ticker\": \"HIGHNY-24JAN01-T60\",\n \"side\": \"bid\",\n \"price\": \"0.5700\",\n \"count\": \"8.00\",\n \"client_order_id\": \"8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1\",\n \"updated_client_order_id\": \"2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a\",\n \"exchange_index\": 0\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["KALSHI-ACCESS-KEY"] = '<api-key>'
request["KALSHI-ACCESS-SIGNATURE"] = '<api-key>'
request["KALSHI-ACCESS-TIMESTAMP"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n \"ticker\": \"HIGHNY-24JAN01-T60\",\n \"side\": \"bid\",\n \"price\": \"0.5700\",\n \"count\": \"8.00\",\n \"client_order_id\": \"8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1\",\n \"updated_client_order_id\": \"2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a\",\n \"exchange_index\": 0\n}"
response = http.request(request)
puts response.read_body{
"order_id": "3b23c1c7-f4ef-4f0d-8b9a-9e53c61f1a0d",
"client_order_id": "2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a",
"remaining_count": "8.00",
"fill_count": "0.00",
"ts_ms": 1715793690123
}{
"code": "<string>",
"message": "<string>",
"details": "<string>"
}{
"code": "<string>",
"message": "<string>",
"details": "<string>"
}{
"code": "<string>",
"message": "<string>",
"details": "<string>"
}{
"code": "<string>",
"message": "<string>",
"details": "<string>"
}orders
Amend Order (V2)
Endpoint for amending the price and/or max fillable count of an existing event-market order using the V2 request/response shape. The request count is the updated total/max fillable count, equal to already filled count plus desired resting remaining count. This behavior matches the v1 amend endpoints; only the request/response shape differs.
POST
/
portfolio
/
events
/
orders
/
{order_id}
/
amend
Amend Order (V2)
curl --request POST \
--url https://external-api.kalshi.com/trade-api/v2/portfolio/events/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": "HIGHNY-24JAN01-T60",
"side": "bid",
"price": "0.5700",
"count": "8.00",
"client_order_id": "8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1",
"updated_client_order_id": "2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a",
"exchange_index": 0
}
'import requests
url = "https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend"
payload = {
"ticker": "HIGHNY-24JAN01-T60",
"side": "bid",
"price": "0.5700",
"count": "8.00",
"client_order_id": "8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1",
"updated_client_order_id": "2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a",
"exchange_index": 0
}
headers = {
"KALSHI-ACCESS-KEY": "<api-key>",
"KALSHI-ACCESS-SIGNATURE": "<api-key>",
"KALSHI-ACCESS-TIMESTAMP": "<api-key>",
"Content-Type": "application/json"
}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {
'KALSHI-ACCESS-KEY': '<api-key>',
'KALSHI-ACCESS-SIGNATURE': '<api-key>',
'KALSHI-ACCESS-TIMESTAMP': '<api-key>',
'Content-Type': 'application/json'
},
body: JSON.stringify({
ticker: 'HIGHNY-24JAN01-T60',
side: 'bid',
price: '0.5700',
count: '8.00',
client_order_id: '8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1',
updated_client_order_id: '2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a',
exchange_index: 0
})
};
fetch('https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend', options)
.then(res => res.json())
.then(res => console.log(res))
.catch(err => console.error(err));<?php
$curl = curl_init();
curl_setopt_array($curl, [
CURLOPT_URL => "https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "POST",
CURLOPT_POSTFIELDS => json_encode([
'ticker' => 'HIGHNY-24JAN01-T60',
'side' => 'bid',
'price' => '0.5700',
'count' => '8.00',
'client_order_id' => '8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1',
'updated_client_order_id' => '2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a',
'exchange_index' => 0
]),
CURLOPT_HTTPHEADER => [
"Content-Type: application/json",
"KALSHI-ACCESS-KEY: <api-key>",
"KALSHI-ACCESS-SIGNATURE: <api-key>",
"KALSHI-ACCESS-TIMESTAMP: <api-key>"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"strings"
"net/http"
"io"
)
func main() {
url := "https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend"
payload := strings.NewReader("{\n \"ticker\": \"HIGHNY-24JAN01-T60\",\n \"side\": \"bid\",\n \"price\": \"0.5700\",\n \"count\": \"8.00\",\n \"client_order_id\": \"8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1\",\n \"updated_client_order_id\": \"2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a\",\n \"exchange_index\": 0\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("KALSHI-ACCESS-KEY", "<api-key>")
req.Header.Add("KALSHI-ACCESS-SIGNATURE", "<api-key>")
req.Header.Add("KALSHI-ACCESS-TIMESTAMP", "<api-key>")
req.Header.Add("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.post("https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend")
.header("KALSHI-ACCESS-KEY", "<api-key>")
.header("KALSHI-ACCESS-SIGNATURE", "<api-key>")
.header("KALSHI-ACCESS-TIMESTAMP", "<api-key>")
.header("Content-Type", "application/json")
.body("{\n \"ticker\": \"HIGHNY-24JAN01-T60\",\n \"side\": \"bid\",\n \"price\": \"0.5700\",\n \"count\": \"8.00\",\n \"client_order_id\": \"8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1\",\n \"updated_client_order_id\": \"2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a\",\n \"exchange_index\": 0\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://external-api.kalshi.com/trade-api/v2/portfolio/events/orders/{order_id}/amend")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["KALSHI-ACCESS-KEY"] = '<api-key>'
request["KALSHI-ACCESS-SIGNATURE"] = '<api-key>'
request["KALSHI-ACCESS-TIMESTAMP"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n \"ticker\": \"HIGHNY-24JAN01-T60\",\n \"side\": \"bid\",\n \"price\": \"0.5700\",\n \"count\": \"8.00\",\n \"client_order_id\": \"8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1\",\n \"updated_client_order_id\": \"2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a\",\n \"exchange_index\": 0\n}"
response = http.request(request)
puts response.read_body{
"order_id": "3b23c1c7-f4ef-4f0d-8b9a-9e53c61f1a0d",
"client_order_id": "2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a",
"remaining_count": "8.00",
"fill_count": "0.00",
"ts_ms": 1715793690123
}{
"code": "<string>",
"message": "<string>",
"details": "<string>"
}{
"code": "<string>",
"message": "<string>",
"details": "<string>"
}{
"code": "<string>",
"message": "<string>",
"details": "<string>"
}{
"code": "<string>",
"message": "<string>",
"details": "<string>"
}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
Your API key ID
RSA-PSS signature of the request
Request timestamp in milliseconds
Path Parameters
Order ID
Query Parameters
Subaccount number (0 for primary, 1-63 for subaccounts). Defaults to 0.
Body
application/json
Market ticker
Side of the order
Available options:
bid, ask Updated price for the order in fixed-point dollars.
Example:
"0.5600"
Updated total/max fillable count for the order. Set this to the order's already filled count plus the desired resting remaining count after the amend.
Example:
"10.00"
The original client-specified order ID to be amended
The new client-specified order ID after amendment
Exchange shard index. If omitted, auto-routes when ticker is provided; otherwise defaults to 0. Use -1 to require auto-routing by ticker.
Example:
0
Response
Order amended successfully
Matching engine timestamp at which the amend was processed, as Unix epoch milliseconds.
Number of resting contracts remaining after the amend. This is the actual post-amend resting quantity, not the request's total/max fillable count. Only present when the amend caused a fill or changed the resting size.
Example:
"10.00"
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"
Volume-weighted average fill price for fills resulting from the amend. Only present when fills occurred.
Example:
"0.5600"
Volume-weighted average fee paid per contract for fills resulting from the amend. Only present when fills occurred.
Example:
"0.5600"