UniFi Switch Buying Guide: PoE Budget, Ports and Layer 3 Explained
How to choose a UniFi switch without overspending — work out your PoE budget, port speeds and whether you need Layer 3, then match it to the right USW model.
Switches look interchangeable until you buy the wrong one and run out of PoE or ports. Three questions decide it: how much PoE, how many ports and how fast, and do you need Layer 3. Let's answer them.
1. PoE budget
Every powered device (AP, camera, phone) draws from the switch's PoE budget (in watts). Add up your devices' draw and leave headroom. A WiFi 7 AP can pull 20W+, a PTZ camera more. A 400W switch comfortably runs a typical office; small sites do fine on a 50–95W Lite switch.
2. Ports and speed
Count your wired devices and pick a port count with room to grow. Then choose speed: gigabit is fine for most desks; go 2.5 GbE if you're deploying WiFi 7 APs; reserve 10 GbE for uplinks, NAS, AV-over-IP and power users.
3. Layer 2 vs Layer 3
Layer 2 switches just switch. Layer 3 switches can route between VLANs at hardware speed — worth it for larger or segmented networks where you don't want all inter-VLAN traffic hairpinning through the gateway.
Matching it to a UniFi switch
Popular UniFi switches
| Feature | Pro 24 PoE | Pro Max 24 PoE | Enterprise 24 PoE |
|---|---|---|---|
| Access ports | 24x GbE | 16x GbE + 8x 2.5 GbE | 12x GbE + 12x 2.5 GbE |
| 10G uplinks | 2x SFP+ | 2x SFP+ | 2x SFP+ |
| Switching capacity | 88 Gbps | 112 Gbps | 124 Gbps |
| PoE budget | 400W | 400W | 400W |
| Layer 3 | Yes | Yes | Yes |
- Home / small office: USW-Lite-8-PoE or Lite-16-PoE
- Standard office: USW-Pro-24-PoE
- WiFi 7 / future-proof office: USW-Pro-Max-24-PoE (2.5 GbE)
- 10 GbE edge / AV: USW-Pro-XG-8-PoE
- Aggregation / core: USW-Aggregation or Pro Aggregation
Shop UniFi switches
Ubiquiti UniFi Switch USW-Lite-8-POE, 4x PoE Output Ports, 52W PoE Supply, Fanless, Wall Mount Kit Included,
Ubiquiti USW-Pro-24-POE Gen2 UniFi 24 Port Gigabit Switch with 802.3bt PoE, Layer3 Features and SFP+
Ubiquiti UniFi Network, 24-Port, POE 400W, (8) 2.5GbEPoE++, (16) GbE Ports - (8) PoE+, (8) PoE++, (2)10G SFP+, Layer3, Rack Mount,
Ubiquiti Pro XG 8 PoE, Compact Desktop/Wall-mountable, Professional-grade 8-port, Layer 3 Etherlighting PoE++ Switch With (8) 10 GbE, (2) 10G SFP+
Ubiquiti UniFi Switch Enterprise 24-port PoE+ 12x2.5GbE 12x1GbE Ports, For Wi-Fi 6 AP, 2x 10g SFP+ Ports, Managed Layer 3 Switch (400W)
Ubiquiti UniFi USW-Aggregation, 8-port 10G SFP+ Aggregation Switch, Layer 2 Switch, Fanless, 1U Rackmount,
They're power levels: PoE (~15W), PoE+ (~30W), PoE++ (~60W) and PoE+++ (~90W) per port. Match the port class to your device — a WiFi 7 AP wants at least PoE+, a PTZ camera often PoE++.
For UniFi, yes — UniFi switches are managed, which is what gives you VLANs, PoE control and per-port insight from the same app as the rest of your network.
Lite and many desktop switches are fanless (silent) — ideal for offices and homes. Larger PoE switches have fans; put them in a comms cupboard.
Related reading
- USW Pro Max 24 PoE review — the 2.5 GbE office switch
- USW Pro XG 8 PoE review — compact 10 GbE
- Which cloud gateway to buy — pair switching with the right gateway
- What is a network switch? — the absolute basics
- Ubiquiti for small business — switching in a full SMB build
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