OnPay Payroll API

Integration requirements for developers

Getting Started

Welcome to OnPay’s payroll API Partner Requirements documentation! Our API enables powerful integrations to our software, simplifying payroll, HR, and benefits for small businesses, accountants, and bookkeepers.

If you are interested in becoming an integration partner, please reach out to developersupport@onpay.com. Also, be sure to check out our API documentation at docs.onpay.com

Integration Requirements

Potential API Partners will first be issued credentials to one of our test environments. After you’ve built your integration, you can submit your application for review.

To ensure optimal performance and security, make sure your application meets the following criteria before submitting for review:


Connection requirements detail how your connection with OnPay is created and maintained.

  • Once connected using OAuth2.0, the connection is maintained until the user chooses to disconnect (signing out of the app does not disconnect).
  • The refresh token is used to retrieve a new access token on expiration. Users should not have to re-authenticate once the access token expires.
  • The user has the ability to disconnect your from OnPay within your app.


Data requirements specify how your app should use OnPay API calls. More information around your data calls will be required in Documentation.

  • Read data from OnPay appears appropriately in-app.
  • Write data to OnPay appears successfully in OnPay.
  • Version control is leveraged to ensure data is the most up-to-date.

See detailed documentation


Integrations are a great way to enhance a user’s experience and give them the power to do more. We want you to be able to share information about OnPay with your audience, so we’ve put together a few guidelines on how to use our name and logos.

You can refer to OnPay products and services with our associated name and logos, so long as such references are truthful, fair, not misleading, and properly represent our brand.


Our company has a rich history, with over 30 years of payroll experience. With that, our brand name has evolved from Payroll Center to OnPay.

Our product and company should be referred to only as “OnPay”.


Approved OnPay logos can be downloaded here.

With the exception of resizing as appropriate, do not alter the logos in any way when using it in your application. Please preserve the integrity of the OnPay logo by maintaining some clear space between the logo and any other visual elements.

On light backgrounds, the logo should be blue.

On darker backgrounds, the white logo can be used.

When space is limited, this version of the logo can be used.


OnPay’s brand colors are:

Primary Colors
Cyan Blue

Hex: #4486C6

RGB: 68, 134, 198

CMYK: 51, 25, 0, 22


Hex: #EC893E

RGB: 236, 137, 62

CMYK: 0, 42, 74, 7



RGB: 255, 255, 255

CMYK: 0, 0, 0, 0

Secondary Colors
Light Grey

Hex: #F8F8F8

RGB: 248, 248, 248

CMYK: 0, 0, 0, 3

Dark Grey

Hex: #525252

RGB: 82, 82, 82

CMYK: 0, 0, 0, 68


Once your integration is built and you feel it meets the specified requirements, you can submit your application for review. Upon successful review, production credentials will be issued and you begin connecting users to OnPay.


Providing documentation helps give OnPay an understanding of what you are trying to accomplish in the integration and explains how a user will interact with it.

  • A short summary on the purpose of the integration.
  • List which endpoints you are using and how you are using them.
  • Account credentials for your app to test the integration.
  • Step-by-step guide on how to use the integration. Videos, screenshots, or any additional tips would be helpful and will result in a faster review.


To submit your request for review, contact us at developersupport@onpay.com with the support documentation.

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