API Versioning

The versions on this page represent breaking changes that we have made to our API since January 2021. The definition of a breaking change is one that causes some code that was written against a prior version of our API to break in the new version. Breaking changes are most commonly caused by either removing or renaming existing fields in the API, or by making a field required that was previously not required. We do not consider adding new endpoints or new fields to existing endpoints breaking changes. For more information on how to use a specific version of our API, please see our page on Versioning.

We release new code, functionality, tests, and other features to the Check API many times per day. However, we do our best in our power to minimize the number of breaking changes that we release to Check's APIs. This is because we want to avoid forcing our customers to change their code to benefit from new features that we've launched to our system. We publish all new changes and features that we release to our product on our Changelog.


  • The amount field on net pay split objects is now optional instead of required. We have added a percentage field, and one of amount or percentage must be specified.


  • The datatype of the approval_deadline field returned on a payroll is now datetime rather than date
  • When creating a post-tax deduction with a type of child_support, the related employee must now have a ssn
  • JSON structure of payroll item warnings has been updated to provide more detail and support additional deduction types


  • amount on earnings and reimbursements for payroll items is now required to be greater than $0.00
  • JSON structure and design of paystub endpoint has been updated to return a breakdown of current earnings in the period


  • phone is now a required field on company



As of August 9th, 2022 this change has been rolled back. phone is no longer a required field to create companies in any API version.


  • Introduced API versioning