VoIP phone systems for Singapore businesses

What a business VoIP phone system is

VoIP (voice over IP) simply means that the voice part of a phone call travels as data over an IP network. For a business, a VoIP phone system usually has three parts that do different jobs:

• The IP PBX. The phone-system software that holds your extensions, ring groups, auto attendant (IVR), call queues, voicemail, recording and reports. It can sit in a server room (on-premise) or be hosted in the cloud.
• The telco connection. Usually a SIP trunk from a carrier. It connects the IP PBX to the public telephone network so you can call and receive calls from ordinary phone numbers. See SIP trunk vs phone lines.
• The endpoints. What your staff actually use: IP desk phones, cordless DECT handsets, headsets, and softphone apps on mobile, desktop and web browser.

Keeping these three parts separate makes quotations easier to compare. A low software price says nothing about the telco service, and a good carrier cannot fix a poorly designed call flow.

IP PBX: on-premise or hosted in the cloud?

An IP PBX does the same job wherever it runs, but the responsibilities change. With an on-premise IP PBX your business owns the hardware, its power and cooling, backups, security patching and remote access. With a hosted or cloud IP PBX, the platform runs in a data centre and is reached over the internet; your team keeps responsibility for the office network and devices.

LinkusPBX is a hosted cloud IP PBX. The provider publishes a 99.9% uptime SLA, built-in security features such as a firewall, TLS/SRTP encryption and a session border controller, and lifetime software updates. For a side-by-side comparison with a traditional office system, read cloud PBX vs PABX.

What you need in the office

• A stable internet connection with enough upload and download capacity for your peak number of simultaneous calls, plus your normal data traffic.
• Router and firewall settings for voice. Prioritise voice traffic (QoS) where your equipment supports it, and disable SIP ALG on the router, which often interferes with VoIP calls.
• Power over Ethernet (PoE) or power adapters for desk phones, and a plan for what happens during a power or internet outage.
• Good Wi-Fi coverage if staff will use mobile apps or cordless phones around the office.

Our network readiness checklist covers each point. We review it with you before ordering, so problems are found during testing rather than on cutover day.

Keeping your Singapore business numbers

Most businesses want to keep the numbers printed on their website, invoices and signage. Whether a number can move depends on the current carrier, the line type and your contract. ISDN numbers, for example, are usually ported as a whole block. Do not cancel your existing lines yourself before the move is confirmed, because a cancelled number may be lost. The steps are explained in our number porting guide, and porting is quoted case by case after we check eligibility.

Features a VoIP phone system gives you

• Auto attendant / IVR menus, ring groups, call queues, call parking and pickup
• Voicemail, call forwarding and time-based routing for after-hours calls
• Linkus apps for Windows, Mac, iOS, Android and web browser, so staff can take office calls away from the desk
• Call recording, call reports and call accounting (office plans list 500 minutes of recording)
• CRM integrations such as HubSpot, Zoho, Salesforce, Bitrix24, Odoo and Microsoft Dynamics 365
• Microsoft Teams integration and WhatsApp messaging, available depending on plan (see Teams & WhatsApp integration)
• Support for most SIP-based IP phones, with auto provisioning for supported models. See IP phones and headsets

Feature availability depends on your plan, licence and configuration. We confirm what is included in your written quotation.

What a VoIP phone system costs

LinkusPBX office packages start at SGD 39 per month for CP10 (10 extensions, 4 concurrent calls) and go up to SGD 329 per month for CP90 (90 extensions, 36 concurrent calls), on an annual commitment. That price covers the cloud IP PBX. The SIP trunk, phone numbers and external calls are quoted per customer, and setup, porting and any hardware are quoted case by case. See all prices and packages and the phone system cost guide for a fair comparison.

How to choose a VoIP provider in Singapore

1. Ask which IP PBX platform is used, and whether the provider is an authorised partner for it.
2. Get the PBX, the SIP trunk and the setup work itemised separately.
3. Size extensions and peak simultaneous calls separately. See extensions vs concurrent calls.
4. Check how existing numbers, desk phones and special lines (fax, alarms, door phones) will be handled.
5. Ask for a demo of the apps your staff will actually use, then test before cutover.

Switching from an existing phone system? We can review your current setup and plan a move to Yeastar LinkusPBX, including number porting.