curl --request POST \
  --url https://sandbox.elementpay.net/api/v1/partner/customers/{customer_id}/accounts/{account_id}/book-transfers/preview \
  --header 'Content-Type: application/json' \
  --header 'X-API-Key: <api-key>' \
  --data '
{
  "to_account_id": 7,
  "amount": "0.50"
}
'

import requests

url = "https://sandbox.elementpay.net/api/v1/partner/customers/{customer_id}/accounts/{account_id}/book-transfers/preview"

payload = {
    "to_account_id": 7,
    "amount": "0.50"
}
headers = {
    "X-API-Key": "<api-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'X-API-Key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({to_account_id: 7, amount: '0.50'})
};

fetch('https://sandbox.elementpay.net/api/v1/partner/customers/{customer_id}/accounts/{account_id}/book-transfers/preview', 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://sandbox.elementpay.net/api/v1/partner/customers/{customer_id}/accounts/{account_id}/book-transfers/preview",
  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([
    'to_account_id' => 7,
    'amount' => '0.50'
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "X-API-Key: <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://sandbox.elementpay.net/api/v1/partner/customers/{customer_id}/accounts/{account_id}/book-transfers/preview"

	payload := strings.NewReader("{\n  \"to_account_id\": 7,\n  \"amount\": \"0.50\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("X-API-Key", "<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://sandbox.elementpay.net/api/v1/partner/customers/{customer_id}/accounts/{account_id}/book-transfers/preview")
  .header("X-API-Key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"to_account_id\": 7,\n  \"amount\": \"0.50\"\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://sandbox.elementpay.net/api/v1/partner/customers/{customer_id}/accounts/{account_id}/book-transfers/preview")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["X-API-Key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"to_account_id\": 7,\n  \"amount\": \"0.50\"\n}"

response = http.request(request)
puts response.read_body

{
  "status": "success",
  "message": "Book-transfer preview",
  "data": {
    "preview_token": "nvbook.eyJhbGciOiJIUzI1NiJ9.preview",
    "currency": "EUR",
    "from_account_id": 21,
    "to_account_id": 31,
    "amount": "10.50",
    "fee": "0.00",
    "receive_amount": "10.50",
    "fee_status": "estimated",
    "expires_at": "2026-07-30T12:10:00+00:00"
  }
}

{
  "status": "error",
  "message": "Unauthorized"
}

{
  "status": "error",
  "message": "Book transfers require the same currency on both accounts",
  "data": null
}

{
  "status": "error",
  "message": "International entity onboarding is not configured",
  "data": null
}