The short answer
Why your NBN bill keeps rising
If your NBN bill keeps creeping up even though you never changed your plan, you are not imagining it, and your retailer is not simply being greedy. The price you pay rests on a wholesale charge that NBN Co (the government-owned company that owns the network) sets your retailer for every line, and that wholesale charge rises on a regulated, CPI-linked schedule almost every year. When the input goes up, retailers pass it through to existing customers, not just new sign-ups, usually with about 30 days notice. There is no default-offer price cap on internet the way electricity has its DMO, so nothing forces the increase to be small. This page explains how NBN pricing is really built, why a "locked in" price rarely stays locked, and how to actually defend your bill.
Here is the core takeaway in one line: your NBN bill rises because NBN Co lifts the regulated wholesale charge under your plan on a CPI-linked schedule, and retailers pass that increase through to existing customers too, so a "locked in" price rarely stays locked. That single idea fixes the two things people get wrong: they assume a price they signed up to is fixed for the life of the plan (it is not, because the input behind it moves), and they assume a price rise means their retailer is gouging them (it usually starts as a wholesale increase they are passing along). The defence is not the intro price. It is a no-lock-in plan plus the habit of watching the ongoing price and switching when a rise notice lands.
Reframe the assumption: you do not really buy a fixed monthly price on the NBN, you buy a margin sitting on top of a wholesale charge that is scheduled to rise. The number on your first bill is a snapshot of that stack on one day, not a promise. Watch the ongoing price and keep the freedom to leave, and the rises stop being a surprise.
The blind spot
Why most "NBN price rise" articles miss the point
Most coverage of NBN price changes does one of three unhelpful things, and each one leaves you blaming the wrong party or chasing the wrong fix.
First, it treats each rise as a one-off news event. A headline announces that this retailer is lifting prices by a few dollars this month, as if it were an isolated decision. It is not. The rises recur because the wholesale charge beneath them is on a regulated schedule that ratchets up most years, so next year there will be another headline, and another.
Second, it frames the retailer as the villain. It is easy to read a price-rise notice as your telco being greedy, and sometimes margin does creep in. But the increase usually starts upstream at NBN Co and is being passed along. Blaming only the retailer hides the structural cause and makes you think switching to a "nicer" brand will save you, when every retailer is buying from the same wholesaler under the same rising prices.
Third, it tells you to lock in a price as the defence, which is precisely backwards. A locked or fixed promotional rate masks the ongoing price you will actually pay once the promo ends, and it does nothing to stop the next wholesale-driven rise. The real protection is the opposite: a no-lock-in plan that lets you leave the moment a rise lands.
How NBN pricing is built, piece by piece
Expert analysis: what really drives your NBN price up
NBN Co is a wholesale monopoly, and its prices are regulated
NBN Co owns the network and does not sell to you directly. It sells wholesale access to retailers, the industry calls them RSPs (Retail Service Providers), such as Telstra, Optus, Aussie Broadband, TPG, iiNet, Vodafone and dozens of smaller telcos. Because that is a monopoly, NBN Co cannot price however it likes: its wholesale charges sit inside a regulated framework called the Special Access Undertaking (the SAU), which the Australian Competition and Consumer Commission, the ACCC, accepted and oversees. The SAU is the rulebook that says how much NBN Co can charge and how those charges may move over time.
The wholesale charge is CPI-linked, so rises are largely baked in
Here is the engine of the recurring rise. The SAU broadly ties the path of NBN Co's wholesale charges to inflation (CPI), with scheduled annual adjustments. That means a baseline increase is effectively pre-programmed: when general prices rise across the economy, the wholesale cost of your line is built to rise with them. This is not a retailer choosing to charge more, it is the regulated wholesale input ticking up on a calendar. So the question is never really "will NBN prices rise", it is "by how much, and when does my retailer pass it on".
Retailers reprice existing customers, not just new sign-ups
When the wholesale charge moves, retailers have a choice: absorb it and shrink their margin, or pass it through. With no consumer price cap on internet and thin retail margins, most pass it through, and crucially they pass it through to existing customers, not only to new sign-ups. That is why your bill rises even though you did nothing. The notice usually arrives about 30 days before the new price applies, often buried in an email or a billing message. In the March 2025 round, the TPG Telecom brands (TPG, iiNet and Vodafone) lifted most NBN tiers by around $5 a month, with some entry tiers moving $2 to $9, while a handful of legacy customers actually dropped, all attributed to rising wholesale costs.
Internet has no DMO, unlike electricity, so nothing caps the rise
It is worth being deliberate about one comparison. In electricity, the regulator sets a Default Market Offer (the DMO) that puts a ceiling on the standing price, so there is a backstop. Internet has no equivalent price cap. The SAU regulates the wholesale charge, but the retail price you finally pay is set by the market, and there is no consumer-facing cap to rein in a retailer that adds generously on top. That is the structural reason the gap between a sharp plan and a lazy one is wide, and the reason a price rise can be larger than the underlying wholesale move on its own would justify.
Interactive explainer
Will my NBN bill rise? The CPI projector
Enter your current monthly price and assume an indicative CPI-linked annual increase. It projects the likely price in 1, 2 and 3 years, so you can see how a "settled" bill keeps drifting upward. It is indicative only, not a quote.
Project your NBN bill over the next three years
Indicative only. Real increases vary by retailer, tier and the actual CPI-linked wholesale move each year.
What is your situation?
Projected price in 3 years
Heads up: you ticked promo pricing, so your real ongoing price is likely higher than the figure entered before any CPI rise even applies.
Good news: with no lock-in, you do not have to accept these rises. Each notice is a free chance to switch to a sharper plan.
We compound your current monthly price by the assumed annual increase and round to the nearest dollar. The annual total is the monthly figure times 12.
Assumptions: a flat, compounding annual increase applied to the ongoing price; real rises are uneven and depend on the year's CPI-linked wholesale move and your retailer's decision to pass it on. Indicative 2026 illustration only. Sources: ACCC, NBN Co Special Access Undertaking, provider price-change notices.
| Time from now | Monthly price | Annual cost | Extra vs today |
|---|---|---|---|
| Today | $80 | $960 | $0 |
| In 1 year | $83 | $1,000 | $40 |
| In 2 years | $87 | $1,038 | $78 |
| In 3 years | $90 | $1,080 | $120 |
What this looks like in real homes
How NBN price changes catch real households out
The mechanics above are not theory. They are exactly how Australian households end up paying more than they meant to:
The "locked in" plan that quietly rose anyway
A household signs up believing the price is fixed for the term, then gets an email giving 30 days notice of a few dollars a month more. The lock-in only ever covered the promo period; the price-rise clause let the retailer pass on the wholesale increase regardless. Nothing was broken, the customer simply misread what "locked in" meant.
The promo that reverted before the CPI rise even hit
A new customer takes a sharp intro price for six months, forgets the ongoing rate, and is surprised when the bill jumps once the promo ends. Then the annual wholesale-linked increase lands on top of that higher ongoing price. They were measuring everything against the intro number, which was never the real price.
The customer who blamed the wrong telco
Annoyed by a rise, a customer switches to a different brand for the same speed tier, only to receive a similar rise notice within the year. Every retailer buys from the same wholesaler under the same rising charges, so brand-hopping without checking the ongoing price just resets the clock.
The household that used the notice as a free exit
A family treats a price-rise notice as a prompt rather than a verdict. Because the plan is month to month, they compare the new ongoing price against the market, find a better no-lock-in plan with a higher Typical Evening Speed, and switch with no install and no exit fee. The rise cost them nothing because they acted inside the notice window.
The insider insight
The "locked in" price is the part that was never locked
Here is the part most NBN coverage never says out loud. The marketing word "locked" almost always attaches to the promotional rate, the part designed to be temporary, while the genuinely durable number, the ongoing price, is left free to move with every wholesale increase. So the figure you remember and feel reassured by is the one engineered to disappear, and the figure that actually defines your bill for most of the relationship is the one nobody puts in the headline. A price-rise notice is not a glitch in that system, it is the system working exactly as designed: the wholesale charge ticks up, the clause lets it through, and inertia does the rest.
The non-obvious truth: on the NBN you cannot buy your way out of price rises by locking in, because the thing that rises sits underneath the lock, in the regulated wholesale charge. The households that come out ahead do the opposite of locking in: they choose no-lock-in plans, ignore the intro price, track the ongoing price, and treat every 30-day rise notice as a free, penalty-free moment to re-shop. Because internet has no DMO to cap the increase, that habit is worth real money.
The practical consequence: never judge an NBN plan by the locked or intro price, and never accept a rise notice by default. The notice is the cheapest moment you will ever have to switch.
Grounded in the analysis
What you should actually do about NBN price rises
Specific moves that follow from how NBN pricing is built, not generic advice.
Choose no lock-in, ignore the intro price
Pick a month-to-month plan and judge it on the ongoing price, not the promo. A lock-in cannot stop a wholesale-driven rise, it only ties you in while it happens. The freedom to leave is the real protection, so keep it.
Treat every rise notice as a free exit
When the roughly 30-day notice arrives, do not accept it by default. It is a material change, so you can usually leave without an exit fee, unless you are still paying off a bundled modem. Compare the new ongoing price against the market before the rise takes effect.
Re-shop on evening speed, not just dollars
When you compare, line up plans on the same speed tier and check the Typical Evening Speed, so you switch to better real performance and not just a cheaper headline. Use our tools to size the plan, then compare retailers.
Not sure which tier fits before you re-shop? Read our NBN plans guide, then run our internet speed test to see what you are getting now.
Current figures, last updated 2026-06-16
Indicative Australian NBN price-change figures for 2026. Sources: the Australian Competition and Consumer Commission (ACCC), NBN Co's Special Access Undertaking (SAU), and provider price-change notices including the March 2025 TPG Telecom round. Real increases vary by retailer, tier and year.
The bottom line
Why your NBN price will keep rising, and what stops it hurting
Your NBN bill is not a fixed monthly price, it is a retail margin sitting on a wholesale charge that NBN Co lifts on a regulated, CPI-linked schedule almost every year. When that input rises, retailers pass it through to existing customers as well as new ones, usually with about 30 days notice, and because internet has no DMO price cap there is nothing forcing the increase to stay small. The "locked in" price you signed up to was mostly the promo, and the promo was always going to end. So stop relying on lock-ins: choose a no-lock-in plan, watch the ongoing price rather than the intro number, and use every price-rise notice as the free, penalty-free moment to re-shop on evening speed. With the cause structural and the rises recurring, that habit is what keeps the next NBN price change from costing you.
Common questions
A Selectra expert answers your NBN price questions
Because the wholesale charge underneath your plan changed even though your plan did not. NBN Co sets your retailer a wholesale price for every line, and that charge rises on a regulated, CPI-linked schedule most years. When it goes up, your retailer passes the increase through to existing customers, usually with about 30 days notice. Your plan name and speed tier stay the same; the cost of the input behind them does not. With no price cap on internet, nothing forces those rises to be small, which is why a bill you thought was settled keeps creeping up year after year.
Yes. NBN Co cannot charge whatever it likes. Its wholesale pricing sits inside a framework called the Special Access Undertaking (the SAU), which the Australian Competition and Consumer Commission (the ACCC) accepted and oversees. The SAU sets the rules for how much NBN Co can charge retailers and how those charges can move over time, with annual changes broadly linked to inflation (CPI). So the increases are not random: they are baked into a regulated schedule. What is not regulated is the retail price you finally pay, because retailers add their own margin on top and there is no consumer price cap on internet.
In most cases, yes, and this is the part that surprises people. Even on a so-called locked-in plan, the terms almost always let the retailer pass on a wholesale or cost increase, usually after giving you about 30 days notice. A genuine price-rise clause is standard across the industry. The notice is also your exit: because most NBN plans are month to month with no lock-in, a price-rise notice is a good moment to compare and switch rather than accept the new figure by default. The thing that protects you is not the contract, it is the freedom to leave it.
The common practice is around 30 days written notice, sent by email or in your billing communications, before a price increase takes effect. Under Australian consumer protections a material change of this kind also gives you the right to leave without an early-exit penalty, unless you are still paying off a bundled modem or device. Treat the notice as a prompt, not a formality: it is the window where switching costs you nothing and staying costs you the full increase, every month, until you act.
Rarely, and that is the trap. A headline "locked" or "fixed" price usually refers to the promotional rate for a set period, after which it reverts to the ongoing price, which itself can rise with the next wholesale increase. The intro figure is the number you remember; the ongoing figure is the number you pay for most of the time you are a customer. The honest defence is to ignore the lock-in language, look at the ongoing price, choose a no-lock-in plan, and re-shop whenever a rise notice lands.
Do not just accept it. First, find the new ongoing monthly price, not the old promo price, so you know the real number. Then compare it against the market on the same speed tier, checking the Typical Evening Speed so you are comparing real performance and not just dollars. Because most plans are month to month, you can switch retailers without any new cabling or installation and without an exit fee, as long as you are not mid-way through paying off a bundled modem. The notice period is precisely when switching is free, so use it.
