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CustomersMerge customers

Merge customers

POST/partners/customers/merge

Folds one or more duplicate customers into a target customer.

Repoints every record on the source customers — invoices, transactions, projects, documents, contacts, addresses, notes and more — at the target, then soft-deletes the sources. This runs in a single transaction and cannot be reversed through the API. Call Preview a customer merge first.

HMAC signature + Bearer access token
Try this request
Invoices APIProjects APIRecurring Invoice Templates API

Request body

targetCustomerUuiduuidrequired

The customer that survives the merge and receives every reference.

sourceCustomerUuidsarrayrequired

Customers to fold into the target and soft-delete. Non-empty, capped at 100 per request. The target UUID is ignored if it also appears here, and duplicates are collapsed.

Responses

200Merge committed. The merged customer is returned at the top level, not under `data`.
400targetCustomerUuid missing, sourceCustomerUuids empty or over 100 entries, no distinct source left after the target is excluded, or a source is a firm-managed customer.
404The target or one of the source customers was not found in this workspace.
401Missing or invalid HMAC signature, expired timestamp, or invalid Bearer token. Troubleshoot
403The credential does not have access to this workspace or resource. Troubleshoot
429Rate limit exceeded (100 requests per minute per clientId). Retry after the Retry-After header. Troubleshoot
POSThttps://api.getcount.com/partners/customers/merge
Request
import crypto from 'node:crypto';

const BASE_URL = 'https://api.getcount.com';
const CLIENT_ID = process.env.COUNT_CLIENT_ID;
const CLIENT_SECRET = process.env.COUNT_CLIENT_SECRET;
const ACCESS_TOKEN = process.env.COUNT_ACCESS_TOKEN;

const method = 'POST';
const signingPath = '/customers/merge';
const timestamp = Math.floor(Date.now() / 1000).toString();
const body = {
  "targetCustomerUuid": "dfa3219e-6af8-4c53-997a-037534f63a35",
  "sourceCustomerUuids": [
    "7c8d9e0f-1a2b-4c3d-8e4f-5a6b7c8d9e0f"
  ]
};
const bodyString = JSON.stringify(body);

const bodyHash = crypto.createHash('sha256').update(bodyString).digest('hex');
const baseString = `${method}:${signingPath}:${timestamp}:${bodyHash}`;
const signature = crypto.createHmac('sha256', CLIENT_SECRET).update(baseString).digest('hex');

const response = await fetch(`${BASE_URL}/partners/customers/merge`, {
  method,
  headers: {
    'x-client-id': CLIENT_ID,
    'x-timestamp': timestamp,
    'x-signature': signature,
    'Content-Type': 'application/json',
    Authorization: `Bearer ${ACCESS_TOKEN}`,
  },
  body: bodyString,
});

console.log(await response.json());
Response · 200
{
  "message": "Successfully merged 1 customer(s) into Acme Corporation",
  "customer": {
    "id": "dfa3219e-6af8-4c53-997a-037534f63a35",
    "customer": "Acme Corporation",
    "email": "contact@acme.com",
    "mainPhone": "+1234567890",
    "website": "https://acme.com",
    "status": "active",
    "notes": "Preferred customer. Net-30 terms.",
    "paymentTerm": "net30",
    "taxNumber": null,
    "taxAutoCalculate": false,
    "taxExcluded": false,
    "contactName": "John Doe",
    "billingAddress": {
      "id": "0b2c1f5e-7a9d-4f2b-9c1e-2a4b6d8e0f12",
      "street": "123 Main St",
      "city": "San Francisco",
      "state": "CA",
      "zipCode": "94102",
      "country": "USA"
    },
    "shippingAddress": null,
    "contacts": [
      {
        "id": "a5da3577-bf85-4e3a-aa73-df85ca69bc67",
        "firstName": "John",
        "lastName": "Doe",
        "email": "john@acme.com",
        "phone": "+1234567890",
        "isPrimary": true
      }
    ],
    "taxes": [],
    "salesRep": null,
    "createdAt": "2026-01-15T10:30:00.000Z",
    "updatedAt": "2026-01-28T14:22:30.000Z"
  },
  "mergedCount": 1
}