Transfer Funds (CoinSwitch Account ↔ Master)

Transfers funds between your CoinSwitch account (main book) and the master account.

This endpoint requires your CoinSwitch API key — not the master account or subaccount API key. Using a master/subaccount key returns 403.

Method	POST
Path	/dma/api/v1/funds/transfer/master-account
Auth	Authenticated (CoinSwitch main book API key).

Body parameters

Parameter	Type	Required	Description
subaccount_id	string	Yes	subaccount_id of the master account's subaccount.
amount	number (decimal)	Yes	Amount to transfer. Must be > 0.
direction	string	Yes	IN (CoinSwitch account → master) or OUT (master → CoinSwitch account).
client_txn_id	string (UUID)	Yes	Idempotency key — unique UUID per transaction.
quote_asset	string	Yes	USDT.

Request

Python

from reference_client import sign_request, BASE_URL
import requests, json, uuid

payload = {
    "subaccount_id": "1000",
    "amount": 500.00,
    "direction": "IN",
    "client_txn_id": str(uuid.uuid4()),
    "quote_asset": "USDT"
}
headers, path = sign_request("POST", "/dma/api/v1/funds/transfer/master-account")
r = requests.post(BASE_URL + path, headers=headers, data=json.dumps(payload))
print(r.json())

Java

Map<String, Object> body = new HashMap<>();
body.put("subaccount_id", "1000");
body.put("amount", 500.00);
body.put("direction", "IN");
body.put("client_txn_id", UUID.randomUUID().toString());
body.put("quote_asset", "USDT");

HttpResponse<String> resp = client.send(
    "POST", "/dma/api/v1/funds/transfer/master-account", null, body);
System.out.println(resp.body());

Go

body := map[string]any{
    "subaccount_id": "1000",
    "amount": 500.00,
    "direction": "IN",
    "client_txn_id": uuid.New().String(),
    "quote_asset": "USDT",
}
bodyJSON, _ := json.Marshal(body)
headers, p, err := SignRequest("POST", "/dma/api/v1/funds/transfer/master-account", nil)
if err != nil { panic(err) }

req, _ := http.NewRequest("POST", BaseURL+p, bytes.NewReader(bodyJSON))
for k, v := range headers { req.Header.Set(k, v) }
resp, err := http.DefaultClient.Do(req)
if err != nil { panic(err) }
defer resp.Body.Close()
out, _ := io.ReadAll(resp.Body)
fmt.Println(string(out))

Node.js

const {signRequest, BASE_URL} = require('./reference-client');
const crypto = require('crypto');

const body = {
    "subaccount_id": "1000",
    "amount": 500.00,
    "direction": "IN",
    "client_txn_id": crypto.randomUUID(),
    "quote_asset": "USDT"
};

const {headers, path} = signRequest('POST', '/dma/api/v1/funds/transfer/master-account');
const r = await fetch(BASE_URL + path, {
  method: 'POST',
  headers,
  body: JSON.stringify(body),
});
console.log(await r.json());

Response

{
  "message": "transfer successful",
  "data": {
    "txn_id": "exchange_txn_abc123",
    "subaccount_id": "1000",
    "direction": "IN",
    "amount": 500.00,
    "quote_asset": "USDT"
  }
}

Field	Type	Description
data.txn_id	string	Exchange transaction ID.
data.subaccount_id	string	The master subaccount involved.
data.direction	string	Echo of the direction.
data.amount	number	Amount transferred.
data.quote_asset	string	Asset transferred.

Errors

Status	Message	Cause
400	only USDT is supported for master account transfers	Non-USDT quote_asset specified.
400	amount must be greater than zero	Amount is zero or negative.
403	master account does not belong to this user	Master account belongs to a different user.
403	API key belongs to master/subaccount, not coinswitch key	Must use the CoinSwitch API key.
404	subaccount not found	Invalid subaccount_id.
500	internal server error	Unexpected failure.