Description

Comstel ICT · Voice Solutions · Business Grade

SIP Phone Lines

Business-Grade IP Voice Calling Over the Internet

No private IP network required · Use any internet provider · PAYG from $5/line · Unlimited from $25/line

HD Voice Quality
Any Internet Provider
Scalable Lines
PAYG & Unlimited
ISDN Replacement

PAYG From
$5

per line / month

Unlimited From
$25

per line / month

Product Overview

What Are SIP Phone Lines?

SIP (Session Initiation Protocol) Phone Lines are a modern business telephony solution that routes voice calls over your internet connection — replacing traditional copper landlines and ISDN services entirely. Instead of paying for expensive legacy phone infrastructure, your calls travel as data over the internet, delivering crystal-clear HD voice quality at a fraction of the cost.

Comstel ICT’s Business Grade SIP Phone Lines are delivered over Australia’s most reliable telecommunications backbone. There’s no need for a dedicated private IP network — they work over any standard internet connection from any provider. Simply add or remove lines as your business grows, keep your existing phone numbers, and enjoy enterprise-grade voice reliability from as little as $5 per line per month.

Replacing Traditional Landlines & ISDN

With Australia’s copper PSTN and ISDN networks being decommissioned, SIP is the modern, future-proof replacement. Switch to SIP and keep your existing phone system and phone numbers — no disruption to your operations.

Works With Your Existing Phone System

Compatible with IP phones, softphone apps, hosted PBX systems (iPECS, Avaya, 3CX), and legacy PABX systems via an adaptor. No need to replace all your handsets — SIP connects to the infrastructure you already have.

Choose Your Plan

PAYG or Unlimited — Priced Per Line

Pay As You Go

PAYG SIP Line

$5
/line/month

Low monthly fee — pay only for calls you make

Call Rates Per Call

6¢

Local

per call

8¢

National

per call

14¢

Mobile

per call

35¢

13/1300

per call

Best For:

Businesses with lower or unpredictable call volumes who prefer low monthly overheads.

Get a Quote →

Best Value

Unlimited Calls

Unlimited SIP Line

$25
/line/month

Flat-rate — no surprise call costs at end of month

What’s Included

Unlimited

Local · National · Mobile

All included in your flat monthly rate

13/1300 Calls

Charged separately

35¢

per call

Best For:

High call volumes — customer service, sales teams, and operations needing predictable flat-rate billing.

Get a Quote →

Pricing is per line per month. Add as many lines as your business needs — from 1 to 100+. Multi-line discounts available. Contact Comstel ICT for a tailored quote.

Why Choose Comstel SIP Lines

Business-Grade Voice — Built For Australian Businesses

Crystal-Clear HD Voice

Wideband audio codecs deliver HD voice quality — noticeably clearer than traditional PSTN or ISDN calls. Every conversation sounds sharp, natural, and professional.

Use Any Internet Provider

No need for a dedicated private IP network or a specific broadband provider. Comstel SIP lines work over any standard internet connection you already have — NBN, fibre, fixed wireless, or 4G/5G.

Scalable — 1 to 100+ Lines

Add or remove lines instantly as your business grows or downsizes. No expensive hardware changes. Whether you need 1 line or 100, Comstel ICT can scale your service to match your needs today and tomorrow.

Keep Your Existing Phone Numbers

Port your current business numbers across to SIP with no disruption. Your clients keep calling the same numbers — the only thing that changes is the quality and cost of your calls.

Compatible With Your Phone System

Works seamlessly with IP phones, softphones, hosted PBX (iPECS Cloud, Avaya Cloud Office, BizTel, 3CX), and legacy PABX systems. No need to replace handsets or hardware to get started.

Reduce Phone Bills Significantly

Businesses switching from ISDN or PSTN to SIP typically save up to 60% on monthly phone costs. With PAYG rates from 6¢ per call or unlimited for $25/line, the savings add up fast.

Australia’s Most Reliable Network

Delivered over Australia’s most trusted business telecommunications backbone — built for exceptional uptime, voice encryption, and enterprise-grade reliability for business-critical communications.

Fast Setup — Live in Days

Traditional ISDN provisioning could take weeks. SIP lines can be live within days. Comstel ICT guides you through onboarding, compatibility checks, and deployment with minimal disruption to your business.

Self-Service Online Portal

Manage your SIP service online — assign users, update phone numbers, check call performance, view reports, and configure call routing. Full visibility and control without calling for support.

Call Rates Summary

At a Glance — PAYG vs Unlimited

Call Type	PAYG SIP — $5/line/mo	Unlimited SIP — $25/line/mo
Local Calls	6¢ per call	Unlimited ✓
National Calls	8¢ per call	Unlimited ✓
Mobile Calls	14¢ per call	Unlimited ✓
13/1300 Calls	35¢ per call	35¢ per call
Monthly Line Fee	$5 / line	$25 / line

Future-Proofing Your Business

Why Move to SIP Now?

Australia’s traditional copper-based PSTN and ISDN telephone networks are being progressively decommissioned. Businesses still relying on legacy landlines will be forced to migrate at some point — moving now means you get to do it on your own terms, at a time that suits your business, without the pressure of a forced cutover.

60%

Avg. Cost Saving

Typical saving for businesses switching from ISDN to SIP

Days

Setup Time

Live in days — vs weeks for traditional ISDN provisioning

1–100+

Lines Available

Scale up or down instantly — no hardware changes required

Who Benefits

Comstel SIP Lines Are Ideal For

Businesses Replacing ISDN / PSTN

If you’re still on old copper-based landlines, now is the time to upgrade. SIP is the modern replacement — migrate at your pace, keep your numbers, and cut costs immediately.

Customer Service & Call Centres

High-volume inbound and outbound calling at flat-rate pricing. The Unlimited plan’s predictable $25/line billing eliminates the unpredictability of per-minute billing during busy periods.

Offices With Existing PBX / PABX

SIP connects directly to your existing PABX hardware via an adaptor — no need to replace your phone system or handsets. Extend the life of your current investment while upgrading your line infrastructure.

Businesses Moving to Cloud Phone Systems

Connecting to iPECS Cloud, Avaya Cloud Office, BizTel, or 3CX? Comstel SIP lines are the ideal backbone — seamless integration with all major Australian hosted PBX platforms.

Upgrade Your Business Phone Lines Today

Talk to Comstel ICT — Australia’s Business SIP Experts

We’ll assess your current setup, recommend PAYG or Unlimited, and have your SIP lines live with minimal disruption. Contact us for a personalised quote — multi-line discounts available.

1300 070 747
Get a Quote →

Pricing is per line per month. Call rates apply per call as listed. 13/1300 calls are charged separately on all plans at 35¢ per call. International call rates apply and are not included in any plan. Pricing subject to change — contact Comstel ICT for current confirmed rates. Multi-line discounts available for businesses requiring multiple lines. A standard internet connection is required (minimum 100Kbps uncontended bandwidth per voice line recommended for optimal call quality).
Comstel ICT · 1300 070 747 ·

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SIP PHONE LINES

Description

Replacing Traditional Landlines & ISDN

Works With Your Existing Phone System

Talk to Comstel ICT — Australia’s Business SIP Experts

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Shopping cart

SIP PHONE LINES

Description

Replacing Traditional Landlines & ISDN

Works With Your Existing Phone System

Talk to Comstel ICT — Australia’s Business SIP Experts

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