Why Is My WiFi So Slow? 7 Common Causes (And How to Fix Them)

You're paying for fast internet, so why is everything buffering? The frustrating truth is that most slow WiFi problems have nothing to do with your internet plan or your ISP. The problem is usually inside your home.

Here are the 7 most common reasons I see when helping people in Geelong, Surf Coast, and Bellarine - and how to fix each one.

1. Your router is in the wrong spot

This is the #1 cause of slow WiFi I see in Australian homes.

The problem: WiFi signals radiate outward from your router. If it’s tucked in a cupboard, behind the TV, or in the corner of the house, half your signal is being wasted.

Signs it’s this:

• WiFi is fast near the router, slow in bedrooms
• You have “dead zones” in parts of the house
• Moving closer to the router fixes the problem

The fix:

• Move the router to a central, elevated location
• Keep it out of cupboards and off the floor
• Away from metal objects, mirrors, and fish tanks
• Not behind the TV (TVs block signal)

2. Too many devices on 2.4GHz

Your router broadcasts two WiFi networks: 2.4GHz and 5GHz.

The problem: 2.4GHz has better range but is much slower and gets congested easily. If all your devices are connecting to 2.4GHz, they’re fighting for bandwidth.

Signs it’s this:

• You have lots of smart home devices (they usually use 2.4GHz)
• Slow speeds even when you’re close to the router
• Your network name doesn’t indicate which band you’re on

The fix:

• Connect phones, laptops, and tablets to 5GHz when possible
• 5GHz is faster but shorter range - use it for devices near the router
• Keep 2.4GHz for smart home devices, printers, and devices far from the router
• Some routers let you create separate network names for each band

3. Neighbours’ WiFi interference

In Australia’s suburbs, houses are close together. If you can see your neighbours’ WiFi networks, they’re competing with yours.

The problem: WiFi uses shared radio channels. If everyone’s on the same channel, you’re all slowing each other down.

Signs it’s this:

• Slow WiFi in the evenings when neighbours are home
• You can see 10+ other networks from your house
• Problems started when new neighbours moved in

The fix:

• Log into your router and change the WiFi channel
• For 2.4GHz: Try channels 1, 6, or 11 (the only non-overlapping ones)
• For 5GHz: Try channel 36, 40, 44, 48, or higher
• Let your router auto-select if you’re not sure

4. Old router hardware

Routers age faster than you’d think. WiFi standards improve every few years, and older routers can’t keep up with modern devices.

The problem: A 5+ year old router may not support current WiFi standards, has weaker processors, and less memory.

Signs it’s this:

• Your router is from your original NBN installation
• You’ve never upgraded or replaced it
• Newer devices (iPhone 14+, recent laptops) are slower than old devices

The fix:

• If your router is 5+ years old, it’s time to upgrade
• Look for WiFi 6 (802.11ax) routers - they handle multiple devices better
• Don’t use the free router your ISP provided if it’s old
• Budget around $150-300 for a decent home router

5. Your house is too big for one router

This isn’t a criticism - Australian homes are often large, single-storey, and spread out. One router simply can’t cover 200+ square metres through multiple walls.

The problem: Physics. WiFi signal gets weaker with distance and loses strength passing through walls, especially brick and concrete.

Signs it’s this:

• Great WiFi in one part of the house, terrible in others
• The far end of the house is always slow
• You have thick walls or a split-level home

The fix:

• Consider a mesh WiFi system (like Google Nest, TP-Link Deco, or Ubiquiti)
• Mesh systems use multiple units that work together
• They’re designed for coverage, not just speed
• Properly set up mesh beats range extenders every time

6. Background devices hogging bandwidth

Modern homes have 20-40 connected devices. Many of them use bandwidth you don’t even notice.

The problem: Smart TVs, security cameras, backup software, and app updates all use bandwidth in the background.

Signs it’s this:

• Random slowdowns that come and go
• Slow speeds during business hours (work devices backing up)
• You have multiple streaming devices, cameras, or smart home gear

The fix:

• Check what’s connected to your network (router admin page shows this)
• Pause or schedule backups for overnight
• Reduce security camera quality settings if they’re cloud-based
• Consider QoS (Quality of Service) settings to prioritise important devices

7. Your internet plan is actually slow

Sometimes it really is the internet, not the WiFi.

The problem: You’re paying for a slow plan, or you’re not getting the speeds you’re paying for.

Signs it’s this:

• Slow speeds on wired AND wireless connections
• Slow at all times, not just in certain rooms
• You’re on an entry-level NBN plan (NBN 25 or Basic)

The fix:

• Run a speed test on a device plugged directly into the router via Ethernet cable
• Compare the result to what you’re paying for
• If wired is slow too, contact your ISP
• Consider upgrading your plan if it’s genuinely too slow for your household

Quick diagnosis checklist

Before calling anyone, try these:

1. Restart your router (unplug for 30 seconds, wait 2 minutes after plugging back in)
2. Test wired vs wireless (if wired is fast, it’s a WiFi problem)
3. Test close vs far (if close is fast, it’s a coverage problem)
4. Test different times (if evenings are slow, it’s congestion)
5. Test different devices (if one device is slow, it’s that device)

Still slow? Get a proper assessment

If you’ve tried everything and your WiFi is still frustrating, it might be time for a professional look. I help homeowners in Geelong, Surf Coast, and Bellarine sort out WiFi problems without the jargon.

Common questions

Will a WiFi extender fix my slow WiFi? Maybe, but usually no. Extenders repeat a weak signal, so you get slightly better coverage but often slower speeds. Mesh systems are better for coverage problems.

Should I call my ISP? Only if your wired connection is also slow. If wired is fast but wireless is slow, your ISP can’t help - the problem is inside your home.

Do I need to upgrade my NBN plan? Not if only certain rooms are slow. That’s a WiFi problem, not an internet problem. Paying for faster internet won’t fix WiFi coverage.

Is my router too old? If it’s more than 5 years old, probably yes. WiFi technology has improved significantly. A modern router can make a noticeable difference.

Why is WiFi slow in the evenings? Usually neighbour interference - everyone comes home and turns on their devices. Try changing your WiFi channel.

Serving Geelong, Surf Coast, and Bellarine Peninsula.

Why Oh WiFi - 0489 998 445 - hello@whyohwifi.com.au