Create external account

curl --request POST \
  --url https://api.getlemma.com/v0/external-accounts \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --header 'Idempotency-Key: <idempotency-key>' \
  --data '
{
  "entity_id": "<string>",
  "nickname": "<string>",
  "holder_type": "<string>",
  "routing_number": "<string>",
  "account_number": "<string>",
  "holder_name": "<string>",
  "holder_address": {
    "line1": "<string>",
    "line2": "<string>",
    "city": "<string>",
    "state": "<string>",
    "postal_code": "<string>",
    "country": "<string>"
  }
}
'

import requests

url = "https://api.getlemma.com/v0/external-accounts"

payload = {
    "entity_id": "<string>",
    "nickname": "<string>",
    "holder_type": "<string>",
    "routing_number": "<string>",
    "account_number": "<string>",
    "holder_name": "<string>",
    "holder_address": {
        "line1": "<string>",
        "line2": "<string>",
        "city": "<string>",
        "state": "<string>",
        "postal_code": "<string>",
        "country": "<string>"
    }
}
headers = {
    "Idempotency-Key": "<idempotency-key>",
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {
    'Idempotency-Key': '<idempotency-key>',
    Authorization: 'Bearer <token>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    entity_id: '<string>',
    nickname: '<string>',
    holder_type: '<string>',
    routing_number: '<string>',
    account_number: '<string>',
    holder_name: '<string>',
    holder_address: {
      line1: '<string>',
      line2: '<string>',
      city: '<string>',
      state: '<string>',
      postal_code: '<string>',
      country: '<string>'
    }
  })
};

fetch('https://api.getlemma.com/v0/external-accounts', 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://api.getlemma.com/v0/external-accounts",
  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([
    'entity_id' => '<string>',
    'nickname' => '<string>',
    'holder_type' => '<string>',
    'routing_number' => '<string>',
    'account_number' => '<string>',
    'holder_name' => '<string>',
    'holder_address' => [
        'line1' => '<string>',
        'line2' => '<string>',
        'city' => '<string>',
        'state' => '<string>',
        'postal_code' => '<string>',
        'country' => '<string>'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json",
    "Idempotency-Key: <idempotency-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://api.getlemma.com/v0/external-accounts"

	payload := strings.NewReader("{\n  \"entity_id\": \"<string>\",\n  \"nickname\": \"<string>\",\n  \"holder_type\": \"<string>\",\n  \"routing_number\": \"<string>\",\n  \"account_number\": \"<string>\",\n  \"holder_name\": \"<string>\",\n  \"holder_address\": {\n    \"line1\": \"<string>\",\n    \"line2\": \"<string>\",\n    \"city\": \"<string>\",\n    \"state\": \"<string>\",\n    \"postal_code\": \"<string>\",\n    \"country\": \"<string>\"\n  }\n}")

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

	req.Header.Add("Idempotency-Key", "<idempotency-key>")
	req.Header.Add("Authorization", "Bearer <token>")
	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://api.getlemma.com/v0/external-accounts")
  .header("Idempotency-Key", "<idempotency-key>")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"entity_id\": \"<string>\",\n  \"nickname\": \"<string>\",\n  \"holder_type\": \"<string>\",\n  \"routing_number\": \"<string>\",\n  \"account_number\": \"<string>\",\n  \"holder_name\": \"<string>\",\n  \"holder_address\": {\n    \"line1\": \"<string>\",\n    \"line2\": \"<string>\",\n    \"city\": \"<string>\",\n    \"state\": \"<string>\",\n    \"postal_code\": \"<string>\",\n    \"country\": \"<string>\"\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.getlemma.com/v0/external-accounts")

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

request = Net::HTTP::Post.new(url)
request["Idempotency-Key"] = '<idempotency-key>'
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"entity_id\": \"<string>\",\n  \"nickname\": \"<string>\",\n  \"holder_type\": \"<string>\",\n  \"routing_number\": \"<string>\",\n  \"account_number\": \"<string>\",\n  \"holder_name\": \"<string>\",\n  \"holder_address\": {\n    \"line1\": \"<string>\",\n    \"line2\": \"<string>\",\n    \"city\": \"<string>\",\n    \"state\": \"<string>\",\n    \"postal_code\": \"<string>\",\n    \"country\": \"<string>\"\n  }\n}"

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

{
  "id": "external_account_Bx5nTm8hKw3pVd7c",
  "entity_id": "entity_k7mXp2vR9nTfBw4s",
  "nickname": "Quest Diagnostics Operating Account",
  "routing_number": "021000021",
  "account_number": "123456789",
  "status": "active",
  "created_at": "2026-03-20T18:45:00Z"
}

{
  "error": "holder_address.line1 is required"
}

POST

external-accounts

Create external account

curl --request POST \
  --url https://api.getlemma.com/v0/external-accounts \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --header 'Idempotency-Key: <idempotency-key>' \
  --data '
{
  "entity_id": "<string>",
  "nickname": "<string>",
  "holder_type": "<string>",
  "routing_number": "<string>",
  "account_number": "<string>",
  "holder_name": "<string>",
  "holder_address": {
    "line1": "<string>",
    "line2": "<string>",
    "city": "<string>",
    "state": "<string>",
    "postal_code": "<string>",
    "country": "<string>"
  }
}
'

import requests

url = "https://api.getlemma.com/v0/external-accounts"

payload = {
    "entity_id": "<string>",
    "nickname": "<string>",
    "holder_type": "<string>",
    "routing_number": "<string>",
    "account_number": "<string>",
    "holder_name": "<string>",
    "holder_address": {
        "line1": "<string>",
        "line2": "<string>",
        "city": "<string>",
        "state": "<string>",
        "postal_code": "<string>",
        "country": "<string>"
    }
}
headers = {
    "Idempotency-Key": "<idempotency-key>",
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {
    'Idempotency-Key': '<idempotency-key>',
    Authorization: 'Bearer <token>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    entity_id: '<string>',
    nickname: '<string>',
    holder_type: '<string>',
    routing_number: '<string>',
    account_number: '<string>',
    holder_name: '<string>',
    holder_address: {
      line1: '<string>',
      line2: '<string>',
      city: '<string>',
      state: '<string>',
      postal_code: '<string>',
      country: '<string>'
    }
  })
};

fetch('https://api.getlemma.com/v0/external-accounts', 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://api.getlemma.com/v0/external-accounts",
  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([
    'entity_id' => '<string>',
    'nickname' => '<string>',
    'holder_type' => '<string>',
    'routing_number' => '<string>',
    'account_number' => '<string>',
    'holder_name' => '<string>',
    'holder_address' => [
        'line1' => '<string>',
        'line2' => '<string>',
        'city' => '<string>',
        'state' => '<string>',
        'postal_code' => '<string>',
        'country' => '<string>'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json",
    "Idempotency-Key: <idempotency-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://api.getlemma.com/v0/external-accounts"

	payload := strings.NewReader("{\n  \"entity_id\": \"<string>\",\n  \"nickname\": \"<string>\",\n  \"holder_type\": \"<string>\",\n  \"routing_number\": \"<string>\",\n  \"account_number\": \"<string>\",\n  \"holder_name\": \"<string>\",\n  \"holder_address\": {\n    \"line1\": \"<string>\",\n    \"line2\": \"<string>\",\n    \"city\": \"<string>\",\n    \"state\": \"<string>\",\n    \"postal_code\": \"<string>\",\n    \"country\": \"<string>\"\n  }\n}")

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

	req.Header.Add("Idempotency-Key", "<idempotency-key>")
	req.Header.Add("Authorization", "Bearer <token>")
	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://api.getlemma.com/v0/external-accounts")
  .header("Idempotency-Key", "<idempotency-key>")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"entity_id\": \"<string>\",\n  \"nickname\": \"<string>\",\n  \"holder_type\": \"<string>\",\n  \"routing_number\": \"<string>\",\n  \"account_number\": \"<string>\",\n  \"holder_name\": \"<string>\",\n  \"holder_address\": {\n    \"line1\": \"<string>\",\n    \"line2\": \"<string>\",\n    \"city\": \"<string>\",\n    \"state\": \"<string>\",\n    \"postal_code\": \"<string>\",\n    \"country\": \"<string>\"\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.getlemma.com/v0/external-accounts")

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

request = Net::HTTP::Post.new(url)
request["Idempotency-Key"] = '<idempotency-key>'
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"entity_id\": \"<string>\",\n  \"nickname\": \"<string>\",\n  \"holder_type\": \"<string>\",\n  \"routing_number\": \"<string>\",\n  \"account_number\": \"<string>\",\n  \"holder_name\": \"<string>\",\n  \"holder_address\": {\n    \"line1\": \"<string>\",\n    \"line2\": \"<string>\",\n    \"city\": \"<string>\",\n    \"state\": \"<string>\",\n    \"postal_code\": \"<string>\",\n    \"country\": \"<string>\"\n  }\n}"

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

{
  "id": "external_account_Bx5nTm8hKw3pVd7c",
  "entity_id": "entity_k7mXp2vR9nTfBw4s",
  "nickname": "Quest Diagnostics Operating Account",
  "routing_number": "021000021",
  "account_number": "123456789",
  "status": "active",
  "created_at": "2026-03-20T18:45:00Z"
}

{
  "error": "holder_address.line1 is required"
}

Creates a saved external account that can be used as a destination for transfers. External accounts represent bank accounts outside of Lemma, such as a vendor, payroll provider, or another financial institution. External accounts cannot be edited after creation. If you need to change account details, archive the existing external account and create a new one. See Saved recipients for more on why.

The nickname is visible to the account owner on their Lemma dashboard. Choose something descriptive and recognizable (e.g., “Owner’s Personal Account” rather than “Acct 4821”). We recommend making nicknames unique within a provider.

Headers

Idempotency-Key

string

required

A key that prevents creating a duplicate external account if the same request is retried. Reusing a key returns the originally created account instead of saving a second one. See Idempotency.

Request body

entity_id

string

required

The ID of the entity this recipient belongs to.

nickname

string

required

A human-readable label for this recipient. Displayed on the Lemma dashboard and in transaction history.

holder_type

string

required

Whether the account holder is a business or an individual. One of business or individual.

routing_number

string

required

The 9-digit ABA routing number of the recipient’s bank.

account_number

string

required

The bank account number. Digits only.

holder_name

string

required

The legal name of the account holder.

holder_address

object

required

The account holder’s mailing address. Must be a US address.

Show Address fields

line1

string

required

Street address.

line2

string

Apartment, suite, or unit number.

city

string

required

City name.

state

string

required

Two-letter US state code.

postal_code

string

required

ZIP code.

country

string

required

ISO 3166-1 alpha-2 country code. Must be US.

Response

Returns the created external account object.

string

Unique identifier for the external account, prefixed with external_account_.

entity_id

string

The ID of the entity that owns this external account.

nickname

string

The human-readable label for this external account.

holder_type

string

business or individual.

routing_number

string

The routing number of the account holder’s bank.

account_number

string

The external account’s account number.

status

string

The external account’s status. Always active on creation.

created_at

string

ISO 8601 timestamp of when the external account was created.

{
  "id": "external_account_Bx5nTm8hKw3pVd7c",
  "entity_id": "entity_k7mXp2vR9nTfBw4s",
  "nickname": "Quest Diagnostics Operating Account",
  "routing_number": "021000021",
  "account_number": "123456789",
  "status": "active",
  "created_at": "2026-03-20T18:45:00Z"
}

{
  "error": "holder_address.line1 is required"
}

List external accounts Get book transfer

Getting started

Concepts

Entities

Bank Accounts

Lockbox

Check deposits

Reconciliation

Transactions

External accounts

Book transfers

ACH transfers

Create external account

Headers

Request body

Response

​Headers

​Request body

​Response

Headers

Request body

Response