When you begin as a Paychex partner, you'll receive a "client app" within your sandbox environment. This is your playground to fully explore and test all our public API endpoints.

Once you're ready to move forward and after a successful demo with us, we'll provision a new, specialized "partner app" for you. This dedicated application (what we call the "N1 partner app") will be precisely configured with only the endpoints and profiles essential for your integration.

The key benefit? Your "N1 partner app" comes with a single, unique key and secret. This means you won't need to request or manage individual client app keys and secrets from each of your Paychex clients, streamlining your integration process significantly.

From there, you'll follow our standard integration steps to connect your application seamlessly with Paychex clients.

• Use the RequestClientAccess endpoint to push your app to the client's Paychex Flex account under Integrated Apps.
• Provide the Client's 8-digit displayId to initiate the access request
• when the request succeeds, you will receive a deep link URL, which you can share with the client to complete the set up

Optionally, you can register to 'CLT_ACCESS' webhooks, you will know when the client has agreed and connected to you integration this way so you can take the next step!

Use the cURL example below to submit the client access request.

curl --location 'https://api.paychex.com/management/requestclientaccess' \
--header 'Content-Type: application/json' \
--header 'Authorization: Bearer <Your_bearerToken_here>' \
--data '{
    "displayId":<display_Id>
}'

Sample Response  

{
    "approvalLink": "https://myapps.paychex.com/#?clients=clientId&app=IntegratedApplicationsAppV2&appContext=%7B%22clientId%22:%22008WQ28JLRREFLLE7HRR%22,%22appId%22:%2200H2A1IUK6FRAUE2T6P4%22%7D"
}

Client Setup in Paychex Flex

Your client must complete the following steps in Paychex Flex to approve your Partner App and finish the integration setup:
1. Log in to Paychex Flex as a Flex Admin user.
2. Navigate to Company Settings → Integrated Applications.
3. Locate your Partner App. It will appear with an “Access Requested” status.
4. Open the app and approve the connection.
5. Review and agree to the Third-Party Terms of Use, then click Save to confirm the integration.
 

If your client needs help linking their account, they can contact Paychex Support using:
https://developer.paychex.com/support