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POST
/
communications
/
block-trade-proposals
Propose Block Trade
curl --request POST \
  --url https://external-api.kalshi.com/trade-api/v2/communications/block-trade-proposals \
  --header 'Content-Type: application/json' \
  --header 'KALSHI-ACCESS-KEY: <api-key>' \
  --header 'KALSHI-ACCESS-SIGNATURE: <api-key>' \
  --header 'KALSHI-ACCESS-TIMESTAMP: <api-key>' \
  --data '
{
  "buyer_user_id": "<string>",
  "seller_user_id": "<string>",
  "market_ticker": "<string>",
  "price_centi_cents": 2,
  "centicount": 2,
  "expiration_ts": "2023-11-07T05:31:56Z",
  "buyer_subtrader_id": "<string>",
  "buyer_subaccount": 31,
  "seller_subtrader_id": "<string>",
  "seller_subaccount": 31
}
'
import requests

url = "https://external-api.kalshi.com/trade-api/v2/communications/block-trade-proposals"

payload = {
    "buyer_user_id": "<string>",
    "seller_user_id": "<string>",
    "market_ticker": "<string>",
    "price_centi_cents": 2,
    "centicount": 2,
    "expiration_ts": "2023-11-07T05:31:56Z",
    "buyer_subtrader_id": "<string>",
    "buyer_subaccount": 31,
    "seller_subtrader_id": "<string>",
    "seller_subaccount": 31
}
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({
    buyer_user_id: '<string>',
    seller_user_id: '<string>',
    market_ticker: '<string>',
    price_centi_cents: 2,
    centicount: 2,
    expiration_ts: '2023-11-07T05:31:56Z',
    buyer_subtrader_id: '<string>',
    buyer_subaccount: 31,
    seller_subtrader_id: '<string>',
    seller_subaccount: 31
  })
};

fetch('https://external-api.kalshi.com/trade-api/v2/communications/block-trade-proposals', 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/communications/block-trade-proposals",
  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([
    'buyer_user_id' => '<string>',
    'seller_user_id' => '<string>',
    'market_ticker' => '<string>',
    'price_centi_cents' => 2,
    'centicount' => 2,
    'expiration_ts' => '2023-11-07T05:31:56Z',
    'buyer_subtrader_id' => '<string>',
    'buyer_subaccount' => 31,
    'seller_subtrader_id' => '<string>',
    'seller_subaccount' => 31
  ]),
  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/communications/block-trade-proposals"

	payload := strings.NewReader("{\n  \"buyer_user_id\": \"<string>\",\n  \"seller_user_id\": \"<string>\",\n  \"market_ticker\": \"<string>\",\n  \"price_centi_cents\": 2,\n  \"centicount\": 2,\n  \"expiration_ts\": \"2023-11-07T05:31:56Z\",\n  \"buyer_subtrader_id\": \"<string>\",\n  \"buyer_subaccount\": 31,\n  \"seller_subtrader_id\": \"<string>\",\n  \"seller_subaccount\": 31\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/communications/block-trade-proposals")
  .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  \"buyer_user_id\": \"<string>\",\n  \"seller_user_id\": \"<string>\",\n  \"market_ticker\": \"<string>\",\n  \"price_centi_cents\": 2,\n  \"centicount\": 2,\n  \"expiration_ts\": \"2023-11-07T05:31:56Z\",\n  \"buyer_subtrader_id\": \"<string>\",\n  \"buyer_subaccount\": 31,\n  \"seller_subtrader_id\": \"<string>\",\n  \"seller_subaccount\": 31\n}")
  .asString();
require 'uri'
require 'net/http'

url = URI("https://external-api.kalshi.com/trade-api/v2/communications/block-trade-proposals")

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  \"buyer_user_id\": \"<string>\",\n  \"seller_user_id\": \"<string>\",\n  \"market_ticker\": \"<string>\",\n  \"price_centi_cents\": 2,\n  \"centicount\": 2,\n  \"expiration_ts\": \"2023-11-07T05:31:56Z\",\n  \"buyer_subtrader_id\": \"<string>\",\n  \"buyer_subaccount\": 31,\n  \"seller_subtrader_id\": \"<string>\",\n  \"seller_subaccount\": 31\n}"

response = http.request(request)
puts response.read_body
{
  "block_trade_proposal_id": "<string>"
}
{
  "code": "<string>",
  "message": "<string>",
  "details": "<string>",
  "service": "<string>"
}
{
  "code": "<string>",
  "message": "<string>",
  "details": "<string>",
  "service": "<string>"
}
{
  "code": "<string>",
  "message": "<string>",
  "details": "<string>",
  "service": "<string>"
}
{
  "code": "<string>",
  "message": "<string>",
  "details": "<string>",
  "service": "<string>"
}

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

Body

application/json
​
buyer_user_id
string
required

User ID of the buyer

​
seller_user_id
string
required

User ID of the seller

​
market_ticker
string
required

The ticker of the market for this block trade

​
price_centi_cents
integer<int64>
required

Price in centi-cents

Required range: x >= 1
​
centicount
integer<int64>
required

Number of contracts in centicounts

Required range: x >= 1
​
maker_side
enum<string>
required

The maker side of the trade

Available options:
yes,
no
​
expiration_ts
string<date-time>
required

Expiration time of the proposal

​
buyer_subtrader_id
string

Subtrader ID of the buyer. Provide either this or buyer_subaccount, not both.

​
buyer_subaccount
integer

User-managed subaccount number of the buyer (0 for primary, 1-63 for numbered subaccounts). Provide either this or buyer_subtrader_id, not both.

Required range: 0 <= x <= 63
​
seller_subtrader_id
string

Subtrader ID of the seller. Provide either this or seller_subaccount, not both.

​
seller_subaccount
integer

User-managed subaccount number of the seller (0 for primary, 1-63 for numbered subaccounts). Provide either this or seller_subtrader_id, not both.

Required range: 0 <= x <= 63

Response

Block trade proposal created successfully

​
block_trade_proposal_id
string
required

The ID of the newly created block trade proposal