cTrader ProtoOAAmendOrderReq

The message

Name

ProtoOAAmendOrderReq

Direction

Request, sent by the client

Payload type

PROTO_OA_AMEND_ORDER_REQ, number 2109. This number is what identifies the message on the wire.

Answered by

• ProtoOAExecutionEvent

Fields

Sample

Written by this site from the payload type and fields recorded on this page. It has not been run against a terminal, a server or an account, and the values in it are placeholders. No credential is typed into it: where a field holds one, the placeholder says where it comes from. Nothing is entered on this site.

The three outer keys, clientMsgId, payloadType and payload, are the ones Spotware's page on sending and receiving JSON gives. The sample holds the message's required and repeated fields and leaves the optional ones out. help.ctrader.comchecked 12 Oct 2026

{
  "clientMsgId": "msg-1",
  "payloadType": 2109,
  "payload": {
    "ctidTraderAccountId": 12345678,
    "orderId": 123456
  }
}

Limits that apply at cTrader Open API

Related cTrader messages: Orders and positions

• ProtoOAAmendPositionSLTPReqChanges the stop loss and take profit of an open position. The definition allows it only where the access token has trade permission for the account.
• ProtoOACancelOrderReqCancels a pending order. The definition allows it only where the access token has trade permission for the account.
• ProtoOAClosePositionReqCloses an open position, in full or in part. The definition allows it only where the access token has trade permission for the account.
• ProtoOADealListReqAsks for the account's deals in a period of time. A deal is one execution, so this is the trade history.
• ProtoOADealListResReturns the deals in the period, one page at a time.
• ProtoOAExecutionEventSent when the server accepts or executes an order. It is the answer to the new order, cancel, amend and close requests, and it is also sent when a deposit or withdrawal takes place.
• ProtoOAExpectedMarginReqAsks for an estimate of the margin a trade would need under the account's leverage profile, which the definition says can be done before a new order is sent.
• ProtoOAExpectedMarginResReturns the margin estimate for buying and for selling, for each size that was asked about.
• ProtoOANewOrderReqSends a new order. The definition allows it only where the access token has trade permission for the account.
• ProtoOAOrderErrorEventSent when an order request meets an error. It names the error and, where they apply, the order and the position.
• ProtoOAOrderListReqAsks for the account's orders in a period of time.
• ProtoOAOrderListResReturns the orders in the period, one page at a time.