Start by understanding the decision
The NDIA notes you can ask them to explain a decision, and they can also provide written reasons for their decision.
Why this helps
Understanding why the decision was made helps you work out whether you need an internal review, a plan change, or a Tribunal appeal.
Internal review of a decision (Section 100)
The NDIS explains that if you're not happy with a decision (for example, a decision to approve your plan), the NDIA may be able to review that decision, which is called an internal review of a decision.
In that internal review, the NDIA says it will check if it made the right decision under the law by looking at the facts and circumstances at the time of the review, and may contact you if more information is needed.
People often refer to an internal review as a “Section 100 review”. The NDIA calls this an internal review of a decision.
What this pathway is best for
Use this pathway when your main issue is:
“The NDIA made the wrong decision based on the information at the time.”
Helpful mini-checklist
When requesting an internal review, it helps to have:
- The decision letter and date
- A short summary of what you disagree with
- Any additional information you want considered (the NDIA notes you can provide additional information when you ask for a review)
What is “S48”? (Change of circumstances / plan reassessment)
“S48 review” is an older term used for change of circumstances / plan reassessment. The NDIS “Changing your plan” page explains that language around “reviews” changed after amendments that took effect from 1 July 2022, and that participants can ask to vary or reassess their plan.
It also shows that “Change of Circumstances (CoC) review / S48 review” is older wording associated with a plan reassessment request.
What this pathway is best for
Use this pathway when your main situation is:
“My circumstances or support needs have changed.”
The NDIS change-in-circumstances guidance says changes may affect your plan or eligibility, and you should let them know about changes as soon as you reasonably can.
How you can notify changes
The NDIS lists ways to let them know, including:
- Phone
- An enquiry through the contact page
- Completing a change form
- Sending a letter
- Visiting an office
- Emailing supporting evidence to enquiries@ndis.gov.au
Timing note
The “Changing your plan” page says that if the NDIA agrees to a plan reassessment, it will be actioned within 28 days, and small changes will take no longer than 28 days to action.
Appealing an NDIS decision (after internal review)
What if you still disagree after the internal review? The NDIA explains there are other options if you don't agree with a decision, including internal review pathways and further options beyond that.
The NDIA also references the Administrative Review Tribunal (ART) as part of the merits review system in its “Learning from Merits Review” statement.
Internal review
The NDIA re-checks the decision.
Tribunal review
An external body reviews the decision outcome. The NDIA acknowledges the Tribunal merits review framework.
Because Tribunal processes can be high-stakes, consider seeking professional support before proceeding.
Why reviews fail
Common reasons reviews fail include:
- Not providing enough evidence
- Not understanding the process
- Missing key deadlines
Help-first checklist
- Have you got current evidence that supports what you're asking for?
- Can you explain how your disability impacts day-to-day function (not just diagnosis)?
- Are you using the right pathway (internal review vs plan change)?
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Visit Provider Check →About this page
This page is general information and not legal advice. For high-stakes decisions (especially Tribunal matters), consider getting professional support.