WestFax Fax API

WestFax offers a standards based fax API you can use to empower your applications. We provide a free SDK for easy setup and integration. Our fax API is highly flexible with REST-ful services offering compatibility with all languages including PHP, .NET, Java, HTML, Web, Win 32, etc. The WestFax API supports multiple message formats such as SOAP, REST, JSON & XML. Seamlessly send and receive faxes from within your applications without the expense of complicated custom hardware and software solutions.

Transform your business processes while dramatically improving productivity by adding the ability to fax from within your mission-critical software applications. The WestFax Fax API can be used to integrate WestFax’s Robust Fax Service with many different applications. No more trips to the fax machine or wondering if a fax went through and must be re-sent.

Detailed setup documentation and our guarantee for technical support ensures your IT team can have applications “fax capable” in just a few hours. Integrate the fax functionality any way you want: from an application’s File menu, as a button, or even through a web page.

Use it to send outbound faxes wherever you might be whether on the road or in the office. Because its designed for enterprise-level applications, the WestFax Fax API offers unlimited scalability. Plus, with the industry-leading resources of WestFax, Inc. behind it, you can be assured your faxes always go through safely and securely.

If you’re a developer we’d love to hear about your project needs!! Every project is unique, so give us a call or complete our Developer Registration form to communicate directly with our technical team.

  • Our most popular API Downloads
Developer Resources

We have several repositories on Git Hub offering code samples and demo projects to help kick start your API integration.  View them all here.

WestFax SDK and Demo – C# project with SDK and Demo project.  All source code included.  *Recommended
WestFax API Postman Collection – A postman collection demonstrating methods of the WestFax API.
WestFax PHP Sample – A ready-to-use Php example using the WestFax API.  Includes client side and server side API access.
Technical Documentation (PDF) – Detailed technical documenation of API interfaces.(Updated 09/2018)
Demo App Download – WinForms demo of various API methods.

HIPAA Compliant Fax


WestFax offers a fully HIPAA-PCI Certified fax API with an easy to use Restful interface. We go beyond HIPAA requirements to provide an industry-leading secure fax solution.  SSL/PKI encryption of faxes on server and the only PCI-DSS Certified faxing service.  Transmit medical information more efficiently via fax without compromising security.


Fax from any development environment. Our fax solution easily integrates with the leading EMRs, EHRs, and Clinical Management platforms.  From XML, JSON and/or SOAP message encoding to Java, C# and PHP.  Our flexible and consistent API interface makes your fax project a reality.


Our geographically diverse network provides 99.9% up-time.  Our network architecture has the capacity and speed to scale with your business and will deliver the first dialing attempt within 60 seconds.  The WestFax  topology aware intelligent network provides the highest successful delivery rate.

For Developers

By Developers.   Our off-the-shelf PHP and .NET SDKs  and code samples greatly simplify the development and implementation effort required to get you up and running with API faxing.  Our technical team will assist you in the application process making recommendations of best practices tailored to your needs.

Easy fax integration into your critical business processes – any language – any platform.