OANDA API PUT /v3/accounts/{accountID}/orders/{orderSpecifier}/clientExtensions

PUT/v3/accounts/{accountID}/orders/{orderSpecifier}/clientExtensionsversion v3Orders

Update the client extensions on an order: your own ID, tag and comment, for the order and for the trade it will open. OANDA says not to use them on an account linked to MT4.

Risk warning: CFDs and spread bets are complex instruments and come with a high risk of losing money rapidly due to leverage. You can lose money on these products, and each provider publishes its own loss figure under FCA rules. You should consider whether you understand how they work and whether you can afford to take the high risk of losing your money. Automated and API trading can amplify losses through bugs, connectivity failures and runaway orders.

Independent and unofficialdeveloper.oanda.comchecked 12 Oct 2026

Read on OANDA's own order endpoints page on 12 Oct 2026: method, path, parameters and the top level response fields.

Parameters

Name	In	Type	Description
Accept-Datetime-Format	header	string	Optional. RFC3339 (default) or UNIX for epoch seconds in datetime fields.
Content-Typerequired	header	string	Send application/json on every request with a body.
accountIDrequired	path	string	Account ID from GET /v3/accounts. Mock value shown.
orderSpecifierrequired	path	string	Order ID, or @ followed by your client order ID.
clientExtensions	body	object	The client extensions to set on the order.
tradeClientExtensions	body	object	The client extensions to set on the trade created when the order fills.

Authentication headers

Name	Type	Description
Authorizationrequired	string	Send Bearer followed by your personal access token. Placeholder only: never paste a real token into this site.

Request

Written from the method, path and parameters recorded on this page, against the demo host. Not executed against a live or demo account. Credentials are read from environment variables on your own machine and are never entered on this site. The request builder writes these same snippets, from the same record.

This call takes a request body. The record marks no body field as required, so the samples send an empty JSON object with a Content-Type of application/json (in Python, passing json= sets that header). Add the fields the call needs from the parameters above before the request can succeed.

Python

# Set OANDA_TOKEN, OANDA_ACCOUNT_ID as environment variables first. Never paste real values into code.
# Replace each {placeholder}, "..." and 0 with a real value before running.
# Optional and not shown: headers Accept-Datetime-Format; body fields clientExtensions, tradeClientExtensions.
import os
import requests

BASE_URL = "https://api-fxpractice.oanda.com"  # the demo host
headers = {
    "Authorization": "Bearer " + os.environ["OANDA_TOKEN"],
    "Content-Type": "application/json",
}
body = {}
resp = requests.put(BASE_URL + "/v3/accounts/" + os.environ["OANDA_ACCOUNT_ID"] + "/orders/{orderSpecifier}/clientExtensions", headers=headers, json=body, timeout=10)
resp.raise_for_status()
print(resp.json())

JavaScript

// Set OANDA_TOKEN, OANDA_ACCOUNT_ID as environment variables first. Never paste real values into code.
// Replace each {placeholder}, "..." and 0 with a real value before running.
// Optional and not shown: headers Accept-Datetime-Format; body fields clientExtensions, tradeClientExtensions.
// Run as a module, for example a .mjs file, on a Node version that has fetch built in.
const BASE_URL = "https://api-fxpractice.oanda.com"; // the demo host
const res = await fetch(BASE_URL + "/v3/accounts/" + process.env.OANDA_ACCOUNT_ID + "/orders/{orderSpecifier}/clientExtensions", {
  method: "PUT",
  headers: {
    "Authorization": "Bearer " + process.env.OANDA_TOKEN,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({}),
});
if (!res.ok) throw new Error(`HTTP ${res.status}`);
console.log(await res.json());

curl

# Set OANDA_TOKEN, OANDA_ACCOUNT_ID as environment variables first. Never paste real values into code.
# Replace each {placeholder}, "..." and 0 with a real value before running.
# Optional and not shown: headers Accept-Datetime-Format; body fields clientExtensions, tradeClientExtensions.
curl -X PUT "https://api-fxpractice.oanda.com/v3/accounts/$OANDA_ACCOUNT_ID/orders/{orderSpecifier}/clientExtensions" \
  -H "Authorization: Bearer $OANDA_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{}'

Response

A mock response. The values are invented, so check field names against the official reference.

{
  "_mock": true,
  "orderClientExtensionsModifyTransaction": {
    "id": "9014",
    "orderID": "9010",
    "accountID": "101-004-MOCK-001"
  },
  "relatedTransactionIDs": [
    "9014"
  ],
  "lastTransactionID": "9014"
}

Limits that apply at OANDA

Limit	Value	Scope	Source
Headline limit	120/s per IP address, HTTP 429 above it	ip	developer.oanda.comchecked 3 Oct 2026

OANDA API errors you may meet

All OANDA API error codes, including 236 more not listed here.