Tools January 3, 2026 9 min read

Best Free Softphones for SIP Trunking in 2026

You do not need expensive desk phones to use SIP trunking. These free softphone apps turn your computer or smartphone into a full-featured business phone that connects to your Asterisk or FreePBX system.

What is a Softphone?

A softphone is a software application that acts as a SIP phone. Instead of a physical desk phone, you use your computer or mobile device with a headset. Softphones register to your Asterisk PBX just like a hardware phone would.

Desktop

Windows, Mac, Linux apps

Mobile

iOS and Android apps

WebRTC

Browser-based, no install

Free Softphone Comparison

SoftphonePlatformsTLS/SRTPVideoBest For
LinphoneWin/Mac/Linux/iOS/AndroidYesYesCross-platform, open source
MicroSIPWindowsYesNoLightweight, minimal
Zoiper (Free)Win/Mac/Linux/iOS/AndroidPaid onlyPaidUser-friendly, polished UI
3CX Web ClientWin/Mac/Linux/iOS/AndroidYesYes3CX PBX integration
Grandstream Wave LiteiOS/AndroidYesNoMobile-first, simple

1. Linphone (Best Overall Free Option)

Linphone is fully open-source and works on every platform. It supports TLS, SRTP, and video calling out of the box with no paid upgrades needed.

Pros

  • Fully free and open source
  • All platforms including Linux
  • TLS + SRTP encryption
  • Video calls and messaging
  • Multiple accounts

Cons

  • UI not as polished as paid apps
  • Can be complex to configure
  • Push notifications unreliable on mobile

2. MicroSIP (Best for Windows)

MicroSIP is an ultra-lightweight Windows softphone. The installer is under 10 MB and it uses minimal system resources. Perfect for call center agents or users who just need voice calling.

Pros

  • Tiny footprint (< 10 MB)
  • Starts in seconds
  • TLS/SRTP support
  • Open source
  • No bloat or unnecessary features

Cons

  • Windows only
  • No video calling
  • Basic UI (functional but plain)
  • No mobile version

3. Zoiper Free (Best UI)

Zoiper has the most polished user interface of the free options. The free version supports one SIP account with basic calling. TLS/SRTP and some advanced features require the paid version.

Pros

  • Clean, intuitive interface
  • All platforms
  • Good audio quality
  • Contact integration
  • Easy to set up

Cons

  • TLS/SRTP requires paid ($50)
  • Only 1 account in free version
  • Nag screens for paid features
  • No video in free version

WebRTC: No Install Needed

If you do not want to install any software, WebRTC softphones run directly in your browser. IPComms offers a built-in WebRTC phone in the customer portal:

IPComms WebRTC Phone

  • No software to install - works in Chrome, Firefox, Edge
  • Encrypted by default (WSS + SRTP)
  • Click-to-call from the portal
  • Works alongside your Asterisk system

Asterisk WebRTC: You can also configure Asterisk as a WebRTC server using the built-in HTTP server and WebSocket transport. See our trunk setup guide for WebSocket transport configuration.

Setting Up a Softphone with Asterisk

Regardless of which softphone you choose, the configuration is similar. You need these settings from your Asterisk administrator:

SettingValueNotes
SIP Serveryour-asterisk-ipOr domain name
Username101Your extension number
Password(from admin)Extension secret
TransportUDP or TLSTLS recommended
Port5060 or 50615061 for TLS
CodecG.711 ulawBest quality

Remote Users: If the softphone is outside your office network, ensure your Asterisk firewall allows the user's IP, or set up a VPN. Never expose Asterisk port 5060 to the entire internet.

Try IPComms with Any Softphone

Get a free test trunk and DID. Connect your favorite softphone to our SIP service and make test calls in minutes.

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