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C18: Selected participant is not self-managed. Provide product level details.
An NDIA bulk payment request rejection code, from the NDIA’s own guide (December 2025).
C18
The message
“Selected participant is not self-managed. Provide product level details.”
What it means
A support category was given instead of a support item.
Other claim codes
- C01: Service booking does not exist.
- C02: Service booking for the product entered is still awaiting approval.
- C03: Support start/end dates entered are outside the service booking dates.
- C04: Quantity entered is more than the approved quantity in the service booking.
- C05: No approved service booking exists for the selected product within the selected start/end dates.
- C06: The price entered exceeds the price of the product approved in the selected service booking.
- C07: Participant does not exist in the selected service booking.
- C09: A payment request can only be submitted until 90 days from the service booking end date.
What this tool follows
- NDIS myplace provider portal: Bulk payment requests self-help guide for providers (December 2025): Part 3, payment request rejections
General information only, not financial, legal or claiming advice. Always check a claim against the current official documents.
Questions people ask
What does NDIS claim rejection C18 mean?
C18: "Selected participant is not self-managed. Provide product level details." A support category was given instead of a support item.
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