FOR DEVELOPERS

Add UK calling to the application you are building.

Use standard SIP for the media path and the Sipflex API for account automation. Inbound calls are free, so you pay for the number and capacity rather than every incoming minute.

Self-service by design

Free inbound calls
SIP registration or IP peering
Built-in platform profiles
Dedicated API credentials
Call-event webhooks

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TWO LAYERS

SIP for calls. API for control.

Keep real-time voice traffic on standard telephony protocols while automating the account operations around it.

Free inbound connectivity

Connect your app to a Sipflex number without a per-minute charge for incoming calls.

View platform options

Account automation

Use dedicated credentials to work with numbers, capacity, routing, usage and call records.

Preview the API

THE PUBLIC API STORY

Useful scope, without unnecessary complexity.

Sipflex highlights the API capabilities relevant to trunk customers. Full reference documentation is available in the portal, keeping the public site focused while giving authenticated developers access to the complete system.

Separate API users and credentials
Provisioning and configuration
Call records and usage
Real-time event delivery
Full reference inside the portal

POST /api
Authorization: dedicated-api-credentials

{
  "action": "Get-Channels",
  "context": "account"
}

API capabilities

See the useful public overview and understand where the full authenticated reference lives.

Explore the API

Webhooks

Receive call and account events in your application without polling continuously.

Explore webhooks

30-DAY FREE TRIAL

Start building with UK telephony.

Create a Sipflex account, connect your application and generate separate API credentials when you need automation.

Start free trial

No card required.