Canadian Payroll Tax Library

CPTL is updated whenever CRA updates their documentation of specifications and requirements for payroll withholding calculations – usually on January 1 and July 1 of each year.

Our quality assurance process ensures that all calculations are tested extensively and results match exactly to all CRA test cases. As a payroll software provider, you can be assured that your Canadian tax deduction calculations are up-to-date and accurate with CPTL.

Payroll software vendors typically face the challenge of distributing updates to customers on a timely basis, in advance of implementation dates for new CRA rates and changes in calculation methods. CPTL is updated within 7-10 days of any CRA publication of changes to required payroll withholding rules, which are usually received 30-45 days in advance of the effective date for those changes, allowing our customers ample time to perform their own testing and quality assurance on their payroll application before the new payroll calculations come into effect.  By implementing our CPTL REST API in your payroll software, you don’t need to change anything to implement the updates – CPTL REST API will provide you with updated calculation results in response to your payroll software’s existing REST API requests, based on the payroll payment date value your software sends.

Payroll software developers can significantly reduce development and maintenance time and costs, and increase CRA payroll tax compliance and accuracy by employing CPTL (and QPTL) in their applications. 

CPTL REST API is easy to implement in web-based applications using a standard REST interface.  Download and import our Swagger specification file, obtain your authorized API Key, and start sending payroll deduction calculation requests from your application within minutes.