Switching NBN Plans Mid-Cycle — How Billing Works
Life changes — you might want to upgrade to a faster plan or downgrade to save money. But when can you actually make the switch, and how does the billing work?
Australian NBN providers use one of three billing models when you change plans mid-cycle. They matter a lot if you want to avoid surprise charges, and the difference between them can be worth more than a month's subscription.
1. Pro-Rata Billing
You are charged only for the days you use. Join on the 10th of a 30-day cycle and you pay for the remaining 20 days.
- Joining mid-cycle: You pay for the remaining days of the current cycle
- Leaving mid-cycle: You get credited for the unused days
- Changing plans mid-cycle: You pay pro-rata for both the old and new plan during the overlap period
This is the fairest model — you never pay for a full month of a plan you didn't use the whole month.
2. End-of-Month Changes
Changes take effect at the end of your current billing cycle. You keep paying for your current plan until the cycle ends, then the new plan starts.
- Simple and predictable — you never split a bill between two plans
- Less flexible — an upgrade you make on the 3rd of the month doesn't kick in until the 30th, so you may wait nearly a full month for the speed you paid for
3. 30-Day Notice Required
Some providers require 30 days' notice before changing plans. This means you are locked into your current plan for a full billing cycle after giving notice.
⚠️ This is the most expensive trap in NBN billing. A provider may let you sign up quickly but then hold you to their terms for 30 days after any change. Always check before you commit.
How to Check a Provider's Billing Policy
Every provider on NBN Tracker lists their billing policy on their detail page. We also track:
- Notice periods — how many days of notice are required before a plan change
- Plan change frequency — whether you can upgrade/downgrade daily, monthly, or at fixed intervals
- Static IP availability — included in the plan or available as a paid add-on
Browse all providers and compare their billing policies before committing. If you know your usage might change within the first year — moving house, a new gamer in the house, a remote worker joining — a pro-rata provider with daily plan changes is the safest choice.
FAQ
Can I change plans the same day I sign up?
It depends on the provider's plan-change frequency. Some let you change daily or even on the day, others only monthly. The "Plan changes" row on each provider's page tells you which.
If I cancel mid-cycle, do I get a refund for unused days?
Only under pro-rata billing. End-of-month and notice-based providers charge you for the full cycle regardless of when you leave — which is part of why the 30-day notice model is so expensive to exit.
Does the billing policy apply to upgrades too, or only downgrades?
To both. The same rules govern moving up to a faster tier as moving down. An upgrade under a 30-day-notice provider is just as locked in as a downgrade.
What's the practical cost difference between the billing models?
In the worst case, the difference is roughly a month's bill. Example: on a $100 plan, switching on the 25th of a 30-day cycle costs about $17 under pro-rata billing, but a full $100 under end-of-month billing — and with 30-day notice, you can't switch at all until the notice period passes.
Should billing policy outweigh price when choosing a provider?
For most people, a slightly cheaper plan from a pro-rata, daily-change provider beats a marginally cheaper plan from a 30-day-notice provider, because flexibility has real cash value whenever your needs change. Factor the policy into your true cost before comparing monthly prices.