Do You Need a POE Switch for VOIP Phones? The Honest Answer

This guide explains what POE is, how it applies to IP desk phones, when a dedicated POE switch is necessary versus optional, and what to look for if you do need one. It is written for small Australian businesses setting up a VOIP phone system and trying to work out whether there is additional network hardware required beyond the phones themselves.

What POE Is

POE stands for Power over Ethernet. It is a standard that allows a network cable to carry both data and electrical power to a connected device. Think of it as a two-in-one cable: instead of running a separate power adapter from the phone to a wall socket, the Ethernet cable that connects the phone to your network also powers it. For a comparison of current options, see our guide to the best SIP desk phones in Australia.

A POE switch is a network switch. The box that your devices connect to via Ethernet cables. That has POE capability built in. Each POE port on the switch provides power to a device connected to it. The PoE switch detects and classifies a compatible powered device before supplying power, after which the device draws the allocated power through the Ethernet cable.

Do IP Phones Require POE?

Many IP desk phones support PoE, but PoE support and alternative power options vary by model and SKU. Do not assume a power adapter is included: Yealink and Grandstream package contents vary by model, SKU and seller bundle, and some official datasheets list the adapter as optional or excluded. If you plug that adapter into a wall socket, the phone will power on and work regardless of whether your network switch provides POE. POE is a convenience option, not a requirement.

The reason POE is common in IP phone deployments is practical: it removes one cable per phone. Without POE, each phone needs an Ethernet cable to the switch and a power adapter to a wall socket. With POE, only the Ethernet cable is required. For a five-phone office, that is five fewer power adapters and five fewer power points consumed. For larger deployments, the cable management benefit is significant.

When You Need a POE Switch

You need a POE switch if you want to power your phones via the network cable rather than individual adapters, and your current network switch does not support POE. This is a valid choice but not a mandatory one. The decision usually comes down to cable management preference and available power points near each phone location.

There is one scenario where POE is strongly recommended: if your phones are in locations where there is no nearby power point or where running additional power cabling would be difficult. This is common in reception areas, meeting rooms, and warehouses where desk placement does not align with power outlets. In these cases, POE eliminates the need to run power to the phone location separately.

When You Do Not Need a POE Switch

If every phone desk has a nearby power point and you are comfortable using the included power adapters, you do not need a POE switch. Your existing non-POE network switch will connect the phones to the VOIP service via Ethernet, and the phones will power via their adapters. This is a workable setup for a small office, provided compatible power adapters are available for the selected phones.

Similarly, if you are replacing a small unmanaged switch with a POE switch purely for the phone setup, factor in whether the cost is justified. For a two or three phone office where power points are readily available, using the included adapters and an existing non-POE switch is a simpler and cheaper starting point.

What to Look For in a POE Switch for VOIP

POE Standard: 802.3af vs 802.3at

Most current IP desk phones require either 802.3af POE (maximum 15.4W per port) or 802.3at POE+ (maximum 30W per port). Standard desk phones like the Yealink T33G, T46U, and T54W are 802.3af devices drawing 3 to 5W. Higher-end phones with colour touchscreens and Wi-Fi may draw up to 10W, still within 802.3af. POE+ is generally not required for standard IP desk phones.

An 802.3af switch will power many standard desk phones, but verify the PoE class and accessory requirements of each exact model; some phones or features require 802.3at. If you are also connecting IP cameras or wireless access points via POE, check their power requirements. Those devices often need 802.3at.

Total POE Budget

Every POE switch has a total power budget. The maximum combined wattage it can deliver across all POE ports simultaneously. A switch might have 8 POE ports rated at 15.4W each but a total budget of only 60W, meaning all 8 ports cannot run at full power simultaneously. For IP phones drawing 3 to 5W each, this is rarely a practical constraint. Eight phones at 5W each require 40W total, well within most small switch budgets.

Check the total POE budget only if you are also powering other devices (cameras, access points) from the same switch, or if you are planning significant expansion.

Managed vs Unmanaged

A managed switch is a network switch with configurable settings. You can create VLANs (virtual local area networks), set QoS (quality of service) priority rules, and monitor traffic per port. An unmanaged switch has no configuration options. It plugs in and works immediately with no setup required.

For VOIP specifically, a managed switch allows you to configure QoS, which prioritises voice traffic on your network over other data. This reduces call quality issues during periods of high network activity. An unmanaged switch can be adequate where the network has sufficient capacity and does not require configurable VLAN or QoS controls; assess congestion, simultaneous traffic and network topology rather than using a fixed phone-count threshold. For offices with higher call volumes, video conferencing, or bandwidth-heavy operations running simultaneously, a managed switch with QoS configured is worth the modest additional cost.

AU Pricing Guide for Small Office POE Switches

For 2 to 8 phones, select a switch by the number of PoE-capable ports remaining after any required uplink, as well as its power budget; an “8-port PoE switch” does not necessarily provide eight usable phone ports.

A managed 8-port POE switch suitable for VOIP with QoS capability costs approximately $150 to $300 AUD depending on brand and specification. TP-Link's TL-SG2008P and Netgear's GS308EP are common choices in this price range for small offices.

For larger offices (10 to 24 phones), 24-port managed POE switches are available from $300 to $600 AUD. Cisco, Ubiquiti, and TP-Link all have options in this range with strong AU availability and local warranty support.

The VLAN Consideration for VOIP

A VLAN, or virtual local area network, is a way of logically separating traffic on a physical network. Putting your VOIP phones on a separate VLAN from your computers and other devices is a best practice for larger deployments. A voice VLAN provides logical traffic separation and simplifies applying QoS and security policies; call-quality and security benefits depend on correctly configured prioritisation and access controls.

For a small office with two to five phones on a modern NBN connection, VLAN separation is a recommendation rather than a requirement. If your VOIP provider's support team recommends it, or if you experience call quality issues, ask your network person to configure a voice VLAN. If you have no IT support, start with a simple setup and optimise later if needed.

Recommended Brands for AU Small Business

For 2 to 8 phone deployments in Australian small business offices, TP-Link and NETGEAR both offer unmanaged PoE switch models in Australia. The TP-Link TL-SG1008P provides eight Gigabit Ethernet ports, four of which support PoE+, with up to 64W total PoE power. NETGEAR lists the Australian GS308P SKU in its EOL product list; choose a currently listed model with the required PoE-port count and power budget. Both options are reliable for pure phone deployments with no quality-of-service requirements beyond what the router provides.

The Cisco SG350 series is end-of-sale and should not be presented as a current standard recommendation; consult Cisco's current catalogue and migration guidance for a supported replacement. The Cisco SG350-10P is an end-of-sale model and should not be described as a current readily available choice. Ubiquiti UniFi switches are a popular alternative, particularly for businesses already running UniFi networking infrastructure. The UniFi US-8-150W (eight PoE+ ports, 130W total PoE availability) is approximately $250 to $350 AUD and integrates with the UniFi Network application for centralised management of compatible UniFi devices. For larger offices, compare current supported 24- to 48-port models; the Cisco SG350-28P is end-of-sale.

Power Backup: What POE Means for Emergency Calls

A simple corded handset on a network-powered non-NBN landline can continue operating during a premises power outage; cordless handsets require mains power, and most NBN-connected services will not operate without appropriate backup. VOIP phones, whether powered by a wall adapter or a POE switch, require mains power to function. When the power goes out, VOIP phones go offline unless backup power is in place. For businesses where phone availability during outages matters, including medical practices with after-hours lines, trades businesses with emergency contact numbers, legal offices with on-call requirements, and any business in a regional area with variable grid reliability, this is a practical infrastructure consideration that needs to be addressed during the initial deployment rather than after the first outage.

A UPS should cover every mains-powered on-premises component required by the service-typically the phones or PoE switch, router, and any NBN connection box or NTD used by the access technology. This does not guarantee service if the upstream NBN or carrier network is unavailable. UPS runtime must be sized from the manufacturer's runtime chart using the total measured watt load of every protected device; it varies by UPS model, battery capacity and condition, and connected equipment. AU retail pricing for a suitable 600VA UPS from brands including APC, Eaton, and CyberPower is approximately $150 to $250 AUD from IT retailers and electrical wholesalers. The UPS plugs into the wall outlet, and both the POE switch and router plug into the UPS. For businesses with higher continuity requirements, a generator or higher-capacity UPS sized to the total switch and router load is the appropriate solution.

Cabling: What to Check Before Deploying POE

A POE switch is only as useful as the cabling infrastructure it connects through. POE over Cat5e cable runs up to 100 metres works reliably for standard 802.3af devices. Category 5 can support 10/100 Mbps and standard PoE when compliant and correctly terminated; existing cabling should be tested where its condition, conductor quality or termination integrity is uncertain. Category 5e was standardised around 2001. For pre-existing structured cabling, verify that the complete channel is standards-compliant, correctly terminated, within length limits and suitable for the required Ethernet speed and PoE load. For any new cable runs in Australia, Cat6 is the recommended minimum standard regardless of whether POE is in use, as the cost differential over Cat5e is minimal and the performance headroom is useful for future-proofing.

Wall plates and patch panels in older buildings are a secondary point of failure worth checking. Damaged, poorly terminated or non-compliant jacks and patch-panel connections can cause intermittent Ethernet or PoE faults; test or bypass suspect components when diagnosing unreliable phone power. If you are deploying into a building with existing structured cabling from before 2005, having the end-to-end cabling tested by an IT cabling contractor before committing to POE across all runs is a worthwhile investment. The cost of the switch is often the smallest component in a cabling-related POE problem. When cabling is uncertain, using power adapters for the short term while cabling is upgraded is a lower-risk path.

What Most Businesses Get Wrong

The most common mistake is buying a POE switch before checking whether phones include power adapters. Do not assume every Yealink or Grandstream model includes an adapter; confirm the exact model, regional SKU and seller bundle. A POE switch is a convenience choice, not a requirement. Make the decision based on your cable management preference, not on a false assumption that it is mandatory.

The second mistake is confusing POE standard support with total power budget. A switch rated for 8 POE ports at 15.4W each may have a total budget of 65W, meaning sustained simultaneous full-power operation on all ports is not possible. For phones drawing 3 to 5W each, this is not a practical problem, but it is worth checking if you plan to add cameras or access points to the same switch.

A managed switch with correctly configured QoS can reduce LAN-side voice impairment during congestion, but it cannot prevent call-quality problems caused elsewhere in the network or service path. Base the managed-switch decision on simultaneous calls, available bandwidth, congestion, competing traffic and required VLAN or QoS controls-not on a daily call-count threshold.

Your Next Steps

Check whether the exact phone model, regional SKU or seller bundle includes a compatible power adapter. Decide whether POE is the right choice for your cable management situation. If your existing switch is non-POE and you decide to use adapters, no new switch hardware is needed. Connect the phones via Ethernet and plug the adapters into wall sockets. If you want POE or if your current switch needs replacement, Choose a switch by the number of PoE-capable device ports remaining after the uplink, its total PoE budget and required management features; an eight-port chassis does not necessarily provide eight usable phone ports.

For the next step in your phone setup, see our new IP phone setup guide for the full provisioning walkthrough, or our guide to setting up business phones on NBN for the network preparation steps.