Onboarding guide: Full Procurement Integration for ServiceTitan partners

  • Updated on Mar 27, 2026
  • Published on Mar 14, 2026
  • 4 minute(s) read
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Overview

This guide provides a step-by-step overview of the end-to-end integration process for suppliers connecting with ServiceTitan. It streamlines the supply chain, enhances supplier collaboration, and improves operational efficiency.

Who uses this feature

  • Supply Chain partners, vendors, suppliers

  • Applies to all business types

Overview: Full Procurement Integration through Request Middleware

ServiceTitan uses Request Middleware for an optimized integration. The Request Middleware acts as a bridge between ServiceTitan and supplier APIs, ensuring seamless data exchange. It processes all outbound requests from ServiceTitan, transforming them into the supplier's expected format. It also modifies supplier responses to match ServiceTitan's required structure. This allows suppliers to integrate with ServiceTitan without making any changes to their API. For more, see Full Procurement Integration Request Middleware.

Request Middleware visual

Middleware serves two main functions:

  • Data Transformation: It reformats API requests and responses.

  • Authentication Management: It facilitates secure communication between ServiceTitan and suppliers by handling authentication methods such as OAuth 2.0, API key, and Basic Auth.

Suppliers can integrate in two ways:

  • Using Middleware Templates (Recommended): Define request and response templates to automatically convert outbound requests to a shape that the supplier API understands and supplier API responses back to ServiceTitan's data model.

  • Pass-through Mode: Suppliers modify their APIs to directly accept ServiceTitan's request format without transformation. In this case, the Middleware acts as a pass-through and is still necessary for managing authentication between ServiceTitan and the supplier API.

This guide outlines the essential steps to configure the Middleware for your supplier, define API endpoints, and test the integration.

What you need to get started

Before getting started, ensure the initial setup process is complete. This includes submitting your form, getting it reviewed and approved, and signing all required contracts.

After approval, you'll get an email with the following information:

  • Partner Portal credentials

  • Authentication details

  • API documentation

Note: These details are required to proceed.

Step 1: Set up Postman for API calls

Create an account on the Postman site and download the ServiceTitan Postman collection to test API requests and configurations.

To configure your Authorization settings:

  1. Open the ServiceTitan Request Middleware collection.

  2. Go to the Authorization tab to set up your environment variables.

  3. Enter your Access Token URL provided to you in the email from the product team.

  4. Enter your Client ID and Client Secret generated from the Partner Portal when creating your supply chain application. Client ID and Client Secret generated from the Partner Portal

  5. When you're finished, click Get New Access Token to submit your request.

Step 2: Configure supplier settings

Establish global API settings for authentication and endpoint access.

  1. Go to the Supplier Configuration folder in Postman. Cursor Supplier Configuration

  2. Open the Set Supplier Config request that corresponds to your authentication method (Basic, API key, OAuth2).

  3. Navigate to the request body.

  4. Set the Base URL for your API.
    Example: https://api.supplier.com. BaseURL: https://api.supplier.com. 

  5. Configure your Authentication:        

    1. GlobalBasic

    2. API Key

    3. OAuth2

Note: Supplier-level authentication applies to all endpoints by default. However, per-endpoint authentication can override global settings if needed.

For details on the authentication methods supported by our Request Middleware and how to configure them, see Full Procurement Integration authentication process.

Step 3: Configure API endpoints

Overview

By default, authentication is handled at the supplier level. However, if a specific endpoint requires a different authentication method, you can override the global settings.

Note: Any authorization settings that you add here will override the supplier-level authentication settings.

ServiceTitan uses predefined endpoint names in the URL when making API requests (e.g. /endpoints/{endpointName}/config). Your endpoint configurations must exactly match these names to ensure proper data exchange.

Endpoint names include:

  • account

  • branches

  • pricing

  • purchaseorder

Note: The minimum requirements for integration are Account Setup, Pricing, and Purchase Orders.

Configuration

To configure your endpoints:

  1. In Postman, go to the Endpoint Configuration folder.

  2. Select your endpoint (e.g. Account configuration), and then Endpoint Configuration.

  3. Click Add endpoint configuration.

  4. In the request body, set the API URL. This should match your API documentation. Endpoint configuration folder

  5. Set your Request Template:        

    1. From the side panel, go to Template Configuration > Request Template > Create endpoint request template.

    2. Use the Request templates from our Repository in the request body when configuring your endpoint in Postman. Example templates will demonstrate all available fields and how to access them in the request template.

  6. Set your Response Template:        

    1. From the side panel, go to Template Configuration > Response Template > Create endpoint response template.

    2. Use the Response templates from our Repository in the request body when configuring your endpoint in Postman. Example templates will show the fields that the ServiceTitan API is expecting back in the response.

  7. (Optional) Configure your Error Templates:        

    1. From the side panel, go to Template Configuration > Error Template > Create endpoint error response template.

    2. Use the Error Response template from our Repository in the request body when configuring your endpoint in Postman. Example templates will show the fields that the ServiceTitan API is expecting back in the response.                

      Note: The endpoint error template is used when your API returns a response with a status code of 400 or higher. If no custom error template is specified, the default error template will be applied.

For detailed information about the available generic endpoints, see Full Procurement Integration generic endpoints.

Step 4: Test API calls in Postman

Run tests using mock data to validate your API calls in Postman before integrating with ServiceTitan.

  1. In the Postman Endpoint Configuration tab, select your endpoint (e.g. Account configuration), and then Sandbox.

  2. Enter test data in the request body and ensure the API returns a valid response.

Tip: Always test in Postman first before using the ServiceTitan UI as debugging is easier in Postman than in ServiceTitan's UI.

Step 5: Final testing in ServiceTitan

Validate the integration using ServiceTitian's interface.

  1. Sign in to the ServiceTitan API Credentials Portal.

  2. Test your Account Setup, Pricing, and Purchase Orders.

Tip: Use the customers' Quick Start Guide for a step-by-step guide on enabling supplier integration in ServiceTitan, configuring the pricebook, and understanding purchase order management.

FAQ

Check out the most frequently asked questions for the Full Procurement Integration.

Additional resources

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