# ADP iHCM — HRIS API: connection

> Canonical URL: https://developers.apideck.com/apis/hris/adp-ihcm/connection

# How to connect to ADP iHCM

This guide explains how to connect your ADP iHCM account through Vault.

> **Note**: ADP iHCM is ADP's HR and payroll solution for customers outside the US and Canada (including the UK and Europe). US and Canada customers should use ADP Workforce Now instead.

## Prerequisites

To connect, you need ADP API credentials (Client ID, Client Secret) and a TLS certificate. These are provisioned by ADP after purchasing the **ADP Developer Kit** (also known as Developer's Toolkit).

## Step 1: Purchase the ADP Developer Kit

Contact your ADP representative or the ADP Marketplace ESI team to purchase the Developer Kit. This unlocks API access for your ADP iHCM account.

## Step 2: Generate a TLS certificate

Generate an X.509 certificate using OpenSSL or a similar tool:

```
openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout adp_client.key -out adp_client.crt
```

This creates two files:
- **adp_client.crt**: your public certificate
- **adp_client.key**: your private key

Send the **public certificate** (.crt) to ADP. You can reach the ADP ESI support team at marketplace_esi_client_support@adp.com. You may also need to sign a client instruction agreement with ADP.

Keep the **private key** (.key) secure: you will need it later.

## Step 3: Receive your Client ID and Client Secret from ADP

Once ADP has processed your certificate and agreement, they will provide you with:
- **Client ID**
- **Client Secret**

ADP will also activate the required API access on their side.

## Step 4: Enter credentials in Vault

1. You will receive a Vault connection link from the application you are connecting to.
2. Open the link and select **ADP iHCM**.
3. Enter the following:
   - **Client ID**: from Step 3
   - **Client Secret**: from Step 3
   - **Client Certificate**: paste the full content of the .crt file from Step 2 (including `-----BEGIN CERTIFICATE-----` and `-----END CERTIFICATE-----`)
   - **Client Key**: paste the full content of the .key file from Step 2 (including `-----BEGIN PRIVATE KEY-----` and `-----END PRIVATE KEY-----`)
4. Click **Save**. The connection status should change to **Connected**.

![Vault - ADP iHCM connection](https://res.cloudinary.com/apideck/image/upload/v1777031697/docs/connectors/adp-ihcm/vault-adp-ihcm.png)

## Trouble Authenticating

If you are having trouble connecting:

- Verify that your Client ID and Client Secret are correct.
- Ensure the certificate and key content includes the full PEM headers.
- Confirm with ADP that your API access has been activated.
- Contact ADP support for further assistance.


[API reference](https://developers.apideck.com/apis/hris/reference.md) · [Coverage matrix](https://developers.apideck.com/apis/hris/coverage)