The short answer
What 5G home internet actually delivers
5G home internet promises gigabit speeds, and the marketing leans hard on that one big number. The truth is almost no Australian home ever sees it, because those headline speeds come from high-band millimetre-wave (mmWave) spectrum that fades within a few hundred metres and barely passes through a brick wall. What you actually connect to is mid-band 5G: genuinely fast and usually better than a basic NBN line, but variable, because it is mobile spectrum shared with every phone camped on the same tower. That is why two neighbours on the identical 5G plan can get wildly different speeds, and why your living room and your back bedroom can feel like two different services. This page explains how 5G the radio technology really works, which band you are most likely on, and the three physical factors that decide whether your 5G home internet flies or stutters.
Here is the core takeaway in one line: 5G's gigabit headline comes from high-band mmWave spectrum that barely reaches indoors, so almost every home runs on variable mid-band 5G whose real speed is decided by the band, your distance to the tower and the walls in between, not by the plan you bought. That single idea fixes the two things people get wrong: they expect the advertised gigabit (they will not see it, because mmWave is not at their address), and they assume the plan name guarantees a speed (it does not, because mid-band is shared mobile spectrum with no published evening-speed promise). Understand which band you are on and where you sit relative to the tower, and the variability stops being a mystery.
Reframe the assumption: 5G is not one speed, it is three spectrum bands that behave like completely different technologies. The gigabit number lives on a band (mmWave) that cannot cross a wall, while the speed you live with comes from a band (mid-band) that everyone on the tower shares. So your real 5G speed is a location lottery, and the prize depends on physics you can partly control.
The blind spot
Why most 5G explainers leave you confused
Most articles about 5G do one of three unhelpful things, and each one leaves you expecting a speed your home will never reach.
First, they quote the peak gigabit number as if it were normal. They lead with "up to 1000 Mbps and beyond" and never mention that figure only exists on mmWave, in a handful of dense city blocks, with near line-of-sight to the cell. For a home behind a brick wall a few hundred metres from the tower, that number is pure fiction. The headline describes a lab and a streetcorner, not your lounge room.
Second, they treat 5G as a single technology with a single speed. In reality 5G is a set of spectrum bands that behave nothing alike: low-band travels for kilometres but crawls, mid-band balances reach and speed, and mmWave is blisteringly fast but stopped by a pane of glass. Lumping them together is like averaging a sports car and a bus and quoting one top speed. Which band you are on changes everything, and almost no consumer guide tells you how to find out.
Third, they compare 5G to the NBN as if both gave you a guarantee. They do not. An NBN retailer must publish a Typical Evening Speed; a mobile tower publishes nothing of the kind, and your share of it shifts with how many phones are nearby and how far you sit from the cell. So a guide that says "5G is faster than the NBN" is comparing a fixed promise to a moving target, and setting you up to feel let down at 8pm.
How 5G radio works, band by band
Expert analysis: what really decides your 5G speed
The physics: higher frequency buys speed but loses reach
Every flavour of 5G is just radio waves at a different frequency, and there is an iron trade-off baked into the physics. Higher frequencies carry more data but travel shorter distances and are blocked more easily by solid objects. That is the whole story in one sentence. Low frequencies bend around buildings and reach for kilometres but cannot carry much; high frequencies carry enormous amounts but fade fast and stop at the first wall. The Australian Communications and Media Authority (the ACMA) licenses this spectrum to the carriers in distinct bands, and which band reaches your home decides what 5G can physically do for you.
Mid-band at 3.5 GHz is what most homes really run on
Here is the band that matters for almost everyone. Mid-band 5G, around 3.5 GHz and often called C-band, is the workhorse the carriers built their capacity on. It strikes the practical balance: enough reach to cover a suburb from a tower, enough capacity to deliver real-world speeds in the low hundreds of Mbps. This is the band a fixed home 5G modem usually locks onto, and it is genuinely good, often better than a basic NBN line. But mid-band still loses signal through brick and double glazing, and it is mobile spectrum, so it is shared with every phone on the same tower. That sharing is why the speed is not a fixed number but a band that swings with demand.
mmWave is the gigabit headline that never came home
The eye-watering speeds live on high-band millimetre-wave (mmWave), up around 26 to 28 GHz. It can carry a gigabit and more, but the physics that gives it that capacity also makes it almost useless for the home: it reaches only tens to a few hundred metres, needs near line-of-sight to the cell, and is effectively stopped by a single wall, heavy rain, or even a passing truck. Carriers have deployed it only in dense pockets like stadiums and busy city corners. So when you see the gigabit number, understand that it describes mmWave, and mmWave is almost certainly not what serves your house. This is the single biggest reason 5G home internet underdelivers against its own advertising.
Contention: why a tower's speed is shared, unlike a wired line
The last piece is the one the NBN comparison hides. A wired line is yours alone up to the exchange; a mobile tower's capacity is a single pool split live across every device connected to it. So your 5G speed falls as more phones and homes camp on your tower, especially in the evening. The Australian Competition and Consumer Commission (the ACCC) reports on fixed-wireless and home internet performance through its Measuring Broadband Australia programme, but there is no mandatory Typical Evening Speed for a 5G tower the way there is for an NBN plan. Distance and walls set your ceiling; contention is the variable that makes the same connection feel fast at 8am and sluggish at 8pm.
Interactive explainer
Why does my 5G speed vary?
Pick the band, your distance to the tower and the obstructions in between, and it shows the realistic speed band you can expect, plus the physical reason behind it. It works from the radio physics that actually decides 5G speed, not from a plan label.
See why your 5G home internet flies or stutters
Indicative only. Real speeds also depend on tower congestion, your modem and your device.
What is between you and the tower?
Realistic speed band
Assumptions: indicative real-world speed bands, not peak lab figures. mmWave is stopped by walls and fades within a few hundred metres; mid-band is shared mobile spectrum that swings with distance, obstructions and congestion; low-band reaches far but carries the least. Tower congestion is not modelled here and reduces all figures at peak times. Sources: ACMA spectrum allocations, ACCC Measuring Broadband Australia, carrier coverage data, 2026.
| 5G band | Reach & wall penetration | Indicative home speed | What it is for |
|---|---|---|---|
| Low-band (700 to 850 MHz) | Several km, through walls | ~30 to 100 Mbps | The coverage layer. Reaches far and penetrates buildings, but the slowest 5G. What rural and fringe homes usually get. |
| Mid-band (3.5 GHz, "C-band") | ~1 to 2 km, some wall loss | ~100 to 400 Mbps | The workhorse of Australian 5G. Most home 5G runs here: fast, but shared with every phone on the tower, so it swings with congestion and distance. |
| High-band mmWave (26 to 28 GHz) | ~Tens to a few hundred metres, blocked by walls | ~1000 Mbps and up | The gigabit headline. Almost no home gets it: it needs near line-of-sight to the cell and is deployed only in dense pockets. |
What this looks like in real homes
How the band lottery plays out for real households
The physics above is not theory. It is exactly how Australian households end up baffled by their 5G home internet:
The gigabit ad that never showed up
A renter signs up for 5G home internet expecting the gigabit speed from the campaign. They get a steady 250 Mbps instead, because their home is on mid-band like nearly everyone, and mmWave was never anywhere near their street. The plan was honest about being 5G; the marketing simply showed the band they would never touch.
The back bedroom that drops out
A household gets great 5G speed by the front window and almost nothing in the back bedroom. Nothing is broken: the mid-band signal weakens through each brick wall, so two rooms in the same house behave like two different connections. Moving the modem to the window facing the tower fixes most of it.
The 8pm slowdown with no fault to report
A family finds their 5G flies during the day and stutters every evening. There is no fault to log, because the tower's capacity is shared and the evening crowd thins everyone's share. With no Typical Evening Speed published for a tower, the slowdown is invisible until you live through it.
The regional home stuck on low-band
A property on the fringe of coverage gets reliable 5G that tops out far below the city numbers. It is on low-band, the band built to reach far and pass through walls rather than to go fast. The connection is dependable; it was simply never going to hit mid-band speeds at that distance.
The insider insight
5G is three technologies wearing one logo
Here is the part most 5G explainers never say out loud. When people talk about "5G speed" as if it were one thing, they are blending three bands that obey completely different physics, and the marketing leans on the fastest one while you live on the practical one. The gigabit headline is real, but it lives on mmWave, a band so fragile a single wall defeats it, which is precisely why it never became a home technology. Your actual service rides mid-band, shared with every phone on the tower, so your speed is set less by your plan than by where your house sits relative to the cell and what stands in between.
The non-obvious truth: on 5G you are not buying a speed, you are buying a position in a radio lottery whose odds are set by your band, your distance to the tower and your walls. The homes that get the most from 5G are not the ones on the best plan, they are the ones closest to the tower with the clearest path to it, who place their modem at a window facing the cell. Because a tower publishes no Typical Evening Speed, none of this shows up before you sign, which is exactly why understanding the bands matters more than reading the plan.
The practical consequence: judge 5G home internet by your location relative to the tower and the band you are likely on, not by the gigabit number on the ad. The headline describes a band your home almost certainly cannot reach.
Grounded in the analysis
What you should actually do about 5G speed
Specific moves that follow from how 5G radio works, not generic advice.
Ignore the gigabit headline
That number lives on mmWave, which your home almost certainly cannot reach. Expect mid-band reality of roughly 100 to 400 Mbps, and judge a 5G service against that, not against the campaign figure. If you genuinely need a guaranteed speed, an NBN plan with a published Typical Evening Speed is the safer comparison.
Test, then place the modem with intent
Run a speed test in the room you will use it, then move the modem to a window on the side of the house facing the nearest tower, raised off the floor and clear of thick walls and metal. With mid-band, distance and walls change which band the modem locks onto, so placement can shift your speed materially.
Match the technology to your address
Close to a busy tower with a clear path, 5G can beat a basic line; on the fringe or behind dense brick you may be on slow low-band and an NBN line could serve you better. Decide on physics, not the plan name, and let the speed test be the tiebreaker.
Weighing 5G against a fixed line? Read our guide to home wireless broadband, run an internet speed test, or see how the NBN compares at your address.
Current figures, last updated 2026-06-16
Indicative Australian 5G figures for 2026. Sources: the Australian Communications and Media Authority (ACMA) spectrum allocations, the Australian Competition and Consumer Commission (ACCC) Measuring Broadband Australia programme, and carrier coverage data. Real speeds vary widely with distance to the tower, obstructions and congestion.
The bottom line
Why the band, not the plan, decides your 5G speed
5G is genuinely capable, but it is not one speed, it is three spectrum bands wearing one logo. The gigabit headline lives on mmWave, a band so easily blocked it never became a home technology, while the service you actually use rides mid-band, fast but shared with every phone on the tower and trimmed by your distance and your walls. So 5G home internet is a location lottery: close to a clear tower it can beat a basic line, and on the fringe behind thick brick it falls back to slow low-band. Judge it on the physics at your address, place your modem with intent, and treat the gigabit number as the band you will never reach rather than the speed you were promised. With no published Typical Evening Speed to hold a tower to account, understanding the bands is the only way to know what you are really buying in 2026.
Common questions
A Selectra expert answers your 5G questions
Because the gigabit figure in the ad comes from high-band millimetre-wave (mmWave) spectrum, and your home is almost certainly not on it. mmWave needs near line-of-sight to the tower and barely passes through a single wall, so it is deployed only in tiny dense pockets. What you actually connect to is mid-band 5G (the 3.5 GHz "C-band" layer), which typically delivers somewhere between 100 and 400 Mbps in real homes. On top of that, mid-band is shared mobile spectrum, so when more phones and homes camp on your tower the speed everyone gets drops. Your distance to the tower and the walls in between then trim it further.
It depends entirely on the band. Low-band 5G (around 700 to 850 MHz) passes through walls and travels for kilometres, which is why it is the coverage layer for fringe and regional homes, but it is the slowest flavour. Mid-band at 3.5 GHz still gets indoors but loses some signal through brick and double glazing, which is why placing your 5G modem near a window facing the tower can lift your speed noticeably. High-band mmWave is effectively stopped by a single wall, and even a hand or a passing truck can interrupt it, which is the core reason it never became a mainstream home technology.
The NBN is a wired (or fixed wireless) network where your line is yours: an NBN retailer must publish a Typical Evening Speed, so you have an honest number to compare. 5G home internet is mobile spectrum repurposed for the home, and there is no equivalent guarantee, because your speed is shared with every phone on the same tower and changes with distance, obstructions and congestion. So 5G can be faster than a basic NBN plan on a good day, but it is inherently more variable. For a guarantee you compare on Typical Evening Speed; for 5G you are betting on your location relative to the tower.
For the overwhelming majority of Australian homes, mid-band at 3.5 GHz (often called C-band). It is the layer the carriers have rolled out most widely for capacity in cities and large towns, and it is the band fixed home 5G modems usually lock onto. If you live on the fringe of coverage or in a regional area you may be on low-band instead, which reaches you but runs slower. You are almost never on mmWave unless you are in a specific high-density deployment zone, which is why the gigabit headline so rarely matches reality.
Because mid-band 5G is contended: the tower has a finite pool of capacity and splits it across every device connected to it. In the evening, when phones and home modems on your tower are all busy, the share each one gets falls, so speeds dip at exactly the hours you most want them. This is the same congestion logic that gives the NBN its Typical Evening Speed, except a mobile tower has no equivalent published figure and the contention pool also moves with how many phones happen to be nearby. Distance and obstructions stay constant, but congestion is the variable that makes the same connection feel different at 8am and 8pm.
Sometimes, and it is usually about physics rather than the plan. Move the modem to a window on the side of the house facing the nearest tower, raise it off the floor, and keep it clear of thick walls, metal and mirrors. Because mid-band signal weakens with distance and obstructions, even a few metres can change which band the modem locks onto and how strong the signal is. An external antenna can help fringe homes. But there is a ceiling set by your distance to the tower and how busy that tower is, and no modem placement beats being closer to the cell.
