Reliably transmit documents with our Programmable Fax API over Private IP
More Ways to Fax
Programmable Fax API
Traditional Fax over SIP
Build on a RESTful API with unmatched developer experience and support.

- Automate your processesOur Fax API can help automate your most tedious processes, saving you time and eliminating errors.
- Secure your communicationsSend and receive secure fax wherever you are on our global private IP network.
- Eliminate errorsOur advanced error correction features ensure your faxes get delivered with confidence.
FEATURES
Fax Features for Total Control
Enhanced Security
Safeguard your data with encryption of signaling and media, and transmission over our private network.
Private Network
Strengthen your faxing with a purpose-built, private IP network, and certified fax-ready SIP trunks.
24/7 Support
Our in-house fax-experts are available around the clock, for all of our customers.
Quality Routing
Access premium outbound routing with direct connections to Tier-1 faxing partners across our network.
Set Your Resolution
With our Fax API you can choose between normal, high, or very quality resolution for your faxes.
Protocol Choice
Deliver faxes via T.38 or G.711 pass-through, and control T.38 re-INVITE initiator for deep configurability.
High Reliability
Ensure your faxes are delivered thanks to automatic error correcting and our multi-cloud network architecture.
Elastic Scalability
Scale on-demand to handle as many inbound and outbound faxes as you need, exactly when you need them.
FEB 02, 2021
“It has been helpful to have Pomelo Tech available for troubleshooting fax errors when it is beyond our scope of knowledge.”
USE CASES
Your communications powered by our API
Healthcare
Faxes are used in healthcare to share a patient’s protected health information (PHI) between physicians, and when processing claims forms.
Professional Services
Faxed documents are legally binding and highly condifdential, and so they are often used in law firms to transmit sensitive information.
Government
Financial Services
Real-time Faxing that's HIPAA-Compliance Ready
- Encrypted Fax Signaling and MediaEnable encryption on signaling with TLS and on media with SRTP or ZRTP.
- Secure Private NetworkEliminate the risks of the public internet with our private IP network.
- Real-Time TransmissionSIP Trunks provide reliable, real-time transmission, so no data is stored at any point.
- Automatic Error CorrectionT.38 error correction guarantees accurate delivery of information, with page-by-page confirmation.

Frequently Asked Questions
Most frequent questions and answers
Yes – you can send, receive and manage faxes over your SIP trunks with Pomelo Tech. This allows you to reliably send, receive and manage secure documents without the need for an antiquated fax machine. What’s more – our Programmable Fax API allows you to send and manage faxes programmatically.
Fax over IP (FoIP) is a term used to describe sending faxes using a voice-over IP (VoIP) network. FoIP uses a protocol like T.38 or G.711 to encode the file into a format suitable for sending over SIP trunks.
Fax is still a popular choice in applications where there are legal and regulatory considerations, such as transferring documents that require hard-copy signatures, and protected health information (PHI). It’s also popular as a backup communications method in case of internet connectivity issues.
You can send and receive fax programmatically in just a few lines of code using the Telnyx Programmable Fax API. Learn how to get started by checking our developer docs.