Most slow NBN is not a slow NBN. It is slow Wi-Fi, an old router, or tired copper wiring inside the home — all of which you can test and often fix yourself. Here is how to speed up NBN the right way: diagnose first, then fix in the order that actually works.
Your NBN plan says 100 Mbps, your speed test says 22, and the first instinct is to blame the provider. Sometimes that is fair. But in most Australian homes, the bottleneck is not the network — it is the last few metres inside the house. The good news is that those metres are yours to fix, and the fixes are usually free or cheap. The bad news is that most guides list the same generic tips in no particular order, so people buy a booster they did not need or upgrade a plan that was never the problem. This guide does it differently: one diagnostic test first, then the fixes in the order that matches your result.
How to speed up NBN: start with a wired test
Everything starts with one test, because it splits every slow-NBN complaint into two very different problems.
Plug a laptop or desktop directly into your modem or router with an Ethernet cable, turn Wi-Fi off on that device, close everything else using the connection, and run a speed test. Repeat it once in the morning and once between 7pm and 11pm, the busy evening period. Write both results down.
If the wired test is close to your plan speed but Wi-Fi is slow, your NBN connection is fine. The problem is your wireless setup. Skip to the Wi-Fi section — nothing your provider does will help, because the slowdown happens after the signal reaches your house.
If the wired test is also well below your plan speed, the problem is the line, the plan, or the provider. Check the line and router sections, then the plan and provider section. Do not buy a mesh kit yet — it cannot fix a line that is delivering 20 Mbps to the front door.
If speeds collapse only in the evening, note the pattern. Evening slowdowns on fixed-line NBN are far less common than they used to be — the ACCC’s final Measuring Broadband Australia report found fixed-line NBN connections averaged 99.4 per cent of plan speed during busy evening hours in March 2026 — so a big evening drop is worth investigating rather than accepting. On Fixed Wireless, evening congestion is a known weakness, and the fix is different again.
One more thing before you touch anything: reboot properly. Turn the modem or router and the NBN connection box (if you have one) off at the power point, wait 30 seconds, then power the NBN box back on first, wait for its lights to settle, then the router. NBN Co lists a full power cycle as its first troubleshooting step for a reason — it clears a surprising number of glitches, and it costs nothing.
Fix your Wi-Fi first if the wired test is fine
Wi-Fi is a shared radio signal, not a cable. Everything between the router and your device — walls, floors, mirrors, fish tanks, microwaves — eats into it. Most Wi-Fi problems come down to placement, band, or congestion.
Placement matters more than anything. Put the router in a central, elevated, open spot — on a shelf, not on the floor inside a cupboard or behind the TV. Keep it away from microwaves, baby monitors, cordless phone bases and Bluetooth speakers, which all share or crowd the same radio spectrum. NBN Co’s own in-home guidance warns that metal doors, appliances, mirrors, solid walls and even liquids like fishtanks and hot water systems can reflect or absorb Wi-Fi signal. One room of clear air can be worth more than any settings change.
Use the right band. Most modern routers broadcast on 2.4 GHz, 5 GHz, and — on newer models — 6 GHz. The 2.4 GHz band reaches furthest and passes through walls best, but it is slower and the most crowded. The 5 GHz band is much faster but fades sooner with distance and walls. The 6 GHz band (Wi-Fi 6E and Wi-Fi 7 routers) is the fastest and least congested, but its range is the shortest of the three. If your device is in the same room as the router, 5 GHz or 6 GHz will usually beat 2.4 GHz by a wide margin. If it is two rooms away through brick, 2.4 GHz may be the only band that holds a usable signal at all. Many routers let you split the bands into separate network names so you can choose deliberately instead of letting the router guess.
Check your channels. In apartments and townhouses, dozens of neighbouring networks fight over the same channels, and on the 2.4 GHz band only channels 1, 6 and 11 avoid overlapping each other. Most routers pick a channel automatically, but they do not always pick well. A free Wi-Fi analyser app on your phone shows which channels are crowded near you; if yours is sitting on a congested channel, switching it in the router settings can lift speeds noticeably. On 5 GHz there is more room, and the higher DFS channels are often quieter — though some routers avoid them because they must vacate the channel if they detect radar.
For big or awkward homes, mesh beats boosters. A cheap plug-in booster repeats a weak signal, which usually halves the speed it repeats. A mesh kit uses multiple nodes that cooperate, and if the nodes are connected to each other by Ethernet cable — wired backhaul — they behave almost like extra wired access points. If running cable is not possible, a tri-band mesh kit with a dedicated backhaul band is the next best thing. Expect to pay a few hundred dollars for a decent two- or three-node kit as at October 2026; it is money well spent only if you have already confirmed the wired test is fine and the problem is coverage.
Fix your router: firmware, settings and age
The router is the most overlooked part of the chain, and the one most people never update.
Update the firmware. Router makers patch bugs and security flaws through firmware updates, and some updates improve Wi-Fi stability and speed. Log into your router’s settings (usually at an address like 192.168.1.1 or 192.168.0.1, printed on the router’s label), check the firmware version, and update it if one is available. If your provider supplied the router, check whether it updates automatically — many do, but not all.
Turn on smart queue management if your router has it. When one device starts a big upload — a cloud backup, a game patch, a video upload — it can choke the whole connection for everyone else. This is bufferbloat: the router’s buffers fill up and every packet waits. Smart queue management (SQM), sometimes labelled QoS or “anti-bufferbloat” in gaming routers, paces traffic so one upload cannot starve the rest. If your router offers it, turn it on and set it to roughly 90–95 per cent of your plan speed. If your router has no SQM option, scheduling big uploads for overnight is the manual version of the same fix.
Try a different DNS. DNS is the phone book that turns names like google.com into addresses. A slow DNS server adds a small delay to every new connection. Switching your router’s DNS to a fast public resolver — Cloudflare’s 1.1.1.1 or Google’s 8.8.8.8 are the common choices — will not change your speed-test number, but it can make browsing feel snappier. It is a two-minute change and easy to reverse.
Know when the router itself is the problem. If your router is more than five years old, only supports Wi-Fi 5 (802.11ac) or earlier, and you are on a 100 Mbps or faster plan, it may simply be unable to deliver what you are paying for. NBN Co advises checking that a router supports at least Wi-Fi 6 or newer for the best speeds. A provider-supplied router is convenient, but it is built to a budget; a good standalone Wi-Fi 6 router costs around $200–$400 as at October 2026, and a Wi-Fi 6E or Wi-Fi 7 model costs more again. Buy the router that matches your plan — there is no point pairing a gigabit-capable router with a 50 Mbps plan, or a Wi-Fi 5 router with a 500 Mbps plan.
Fix your line: the fix depends on your NBN technology
If the wired test is slow, the fault may be in the line itself — and the right fix depends on which NBN technology serves your address.
Fibre to the Node (FTTN) — check your internal copper. On FTTN, fibre runs to a cabinet in the street and ageing copper phone line carries the signal the rest of the way. That copper is yours to look after. Plug the modem into the first phone socket — the one closest to where the line enters the house — and test again. Unplug every other phone, filter and unused device from the remaining sockets; each extra socket and metre of internal wiring can drag the signal down. If the speed jumps at the first socket, the problem is your internal wiring, and a licenced cabler can usually tidy it up. If it stays slow at every socket, the fault is likely outside, and your provider can raise it with NBN Co.
Fibre to the Curb (FTTC) — check the connection device. FTTC uses a small connection device that links the copper lead-in to the fibre in the street pit. Make sure it is powered, its lights are steady, and it is not sitting in a spot that overheats. The same first-socket logic applies to the short copper run into the house.
Fibre to the Premises (FTTP) — check the NBN box. On full fibre there is no copper to degrade, so a slow wired test usually means the NBN connection box, the router, or the provider. Check the box’s status lights against NBN Co’s guide for your model, and try a different Ethernet cable and port — cables fail more often than people expect, and a damaged cable can silently negotiate down to 100 Mbps or even 10 Mbps.
Hybrid Fibre Coaxial (HFC) — check splitters and the wall outlet. HFC runs over the old cable-TV coaxial network. Extra splitters, old wall plates and long coax runs can all weaken the signal. If the modem shares an outlet with a TV point through a splitter, try it on the first splitter or a direct outlet if one exists.
Fixed Wireless — check the antenna and the hour. Fixed Wireless serves homes from a nearby tower, and it is the most variable NBN technology: speed depends on distance, line of sight, weather and how many neighbours share the tower. If evenings are the problem and mornings are fine, that is congestion, and no in-home fix will cure it. Check that the outdoor antenna has a clear view of the tower and has not shifted. If performance stays poor, ask your provider whether another technology is available at your address — some Fixed Wireless premises have become eligible for other options over time.
Sky Muster satellite — know its limits. Sky Muster is the service of last resort for the most remote homes. Its latency is around 660 milliseconds because the signal travels to geostationary orbit and back, and no settings change can fix physics. If video calls and real-time work matter to you, satellite broadband from a low-Earth-orbit provider is a different conversation — see our guide to Starlink in Australia.
Fix your devices and apps
Sometimes the connection is fine and the device is the bottleneck.
Old devices cap your speed. A laptop with a Wi-Fi 4 (802.11n) card cannot go faster than its radio allows, no matter how good the router is. Phones more than five or six years old are similar. If one device is slow while everything else is fast, suspect the device, not the network. A $30–$60 USB Wi-Fi adapter can give an old laptop a modern radio — cheaper than a new laptop and often transformative.
Background uploads are silent speed thieves. Cloud photo backups, game downloads, operating system updates and video uploads all consume bandwidth in the background. Check what is running: on a computer, the task manager or activity monitor shows network usage per app. Pause the big ones and re-test. If the speed recovers, you have found your thief.
Turn off the VPN for the test. NBN Co lists VPN use as a common cause of slow speeds, because all your traffic takes a detour through the VPN server. If speeds recover with the VPN off, the VPN is the bottleneck — try a closer server or a different provider before blaming the NBN.
Check for malware. Malware on a device can saturate a connection or hijack traffic. If one device is slow and behaves strangely, run a scan before anything else. NBN Co lists viruses and malware among the common causes of slow speeds for this reason.
Fix your plan and provider
If the wired test is slow at every hour and every socket, the answer may be that you are simply not getting what you pay for.
Compare against your provider’s typical evening speed. Providers publish a typical evening speed for each plan — the speed most customers on that plan can expect between 7pm and 11pm. Compare your wired evening test against that number, not the headline “up to” figure. If you are consistently well below it, contact your provider with your test results, dates and times. The ACCC has said customers on services that do not deliver expected speeds should contact their provider about fixing the issue or moving to a cheaper plan.
Decide whether to upgrade or switch. If your wired test matches your plan but the plan is too slow for the household, the fix is a faster tier — see our guide to NBN speeds for which tier fits. If your wired test is well below your plan, upgrading the tier will not help: a line delivering 25 Mbps will not deliver 100 just because you pay for it. In that case, fix the line first, or switch providers — and note that the ACCC’s final broadband report found little difference between providers’ average performance, so switching helps most when your current provider has a specific fault or congestion problem, not as a magic fix.
Escalate properly. If your provider cannot fix a genuine fault, lodge a formal complaint and keep records of every test and call. If the complaint goes nowhere, the Telecommunications Industry Ombudsman (TIO) is the free, independent next step. It exists for exactly this situation, and providers take TIO complaints seriously.
The Australian context
Australia’s fixed-line NBN is, on the numbers, in good shape. The ACCC’s final Measuring Broadband Australia report — the last in a program that ran from 2017 — found fixed-line connections averaged 99.4 per cent of plan speed in busy evening hours in March 2026, up from 80–85 per cent in the program’s early years. In other words, if your wired test is far below your plan, you are the exception, not the rule — and that is worth knowing when you call your provider, because it means something specific is wrong rather than “the NBN is just slow.”
The other piece of Australian context is that the fastest tiers now demand modern in-home gear. NBN Co’s September 2025 wholesale changes lifted the old 100/20 tier to 500/50 and the old 250/25 tier to 750/50 on fibre and HFC. A household that jumps to a 500 Mbps plan on a five-year-old Wi-Fi 5 router will see almost none of it. The network has moved on; the in-home gear has to move with it.
What this means for you
- Test wired first. One Ethernet test tells you whether the problem is Wi-Fi, the line, or the provider — and stops you buying the wrong fix.
- Wi-Fi fixes are free. Move the router to a central, elevated spot, use 5 GHz or 6 GHz near the router, and clear congested channels before spending anything.
- Update and maintain the router. Firmware updates, smart queue management and a DNS change cost nothing; replacing a five-year-old router is the biggest single upgrade for many homes.
- FTTN homes: check the first socket. Unplug everything else and test at the socket closest to the street — internal copper wiring is the most common hidden fault.
- If the wired test stays slow, escalate with evidence. Log dates, times and results, compare against your provider’s typical evening speed, and take it to the TIO if the provider cannot fix it.