What is Support ratio?
Also known as: 1:2, 1:3, 2:1 support
A support ratio describes how many workers support how many participants at once. 1:1 is one worker to one participant. 1:2 and 1:3 mean one worker shared between two or three participants, with the cost apportioned. 2:1 means two workers are required for a single participant, and both are claimed.
Shared ratios have their own support item numbers, priced as a share of the full rate. The apportionment is the point: a 1:3 shift claims roughly a third of the hourly cost against each participant’s budget.
Ratios must reflect what actually happened. If one participant of a group is absent, the shift ran at a different ratio and the claim should follow — this is a common source of over-claiming in group and centre-based supports.
How the NDIA describes ratios
In the NDIA's SIL guideline, a ratio of support means how many disability support workers provide support and how many participants share it. For example, one worker might support 2 participants, or 2 workers might support 4 participants. Sharing is not compulsory, and the NDIA considers what ratio meets the participant's needs and is value for money.
Individual SIL, meaning one-to-one or greater support 24 hours a day, may be funded for people with life-threatening health needs, frequent behaviours of concern that pose a serious risk, or rapidly increasing support needs.
Claiming shared support
Section 2.5 of the NDIS Pricing Schedule 2026-27 says that when a support is delivered to more than one person at the same time, the amount a provider may claim from each participant is the applicable maximum amount divided by the number of people in the group. A 1:3 group therefore means each of the three participants is charged a third of the applicable maximum amount for the time of the support.
When more than one worker is needed
Some participants need two workers at once (2:1). The NDIA's 2025-26 Pricing Arrangements allowed providers to bill for the time of every worker involved, and gave shadow shifts for participants with complex needs as an example, capped at 6 hours of weekday support a year. Check the current pricing determination and the participant's plan before claiming.
Getting ratios right on the roster
- Roster the ratio set out in the plan and service agreement.
- Record which participants were present for each shift, so the group size used in the claim matches what happened.
- Recalculate when a participant leaves a group or a housemate moves out.
How Rostery helps
Rostery rosters shared and 2:1 shifts, checks each participant's funding before a shift is confirmed, and checks NDIS bulk claim files against current price limits.
Questions people ask
How do you claim a 1:3 group support?
Divide the applicable maximum amount by 3 and claim that amount from each participant's plan for the time of the support.
What does 2:1 support mean?
Two workers support one participant at the same time, usually because of complex health or behaviour support needs.
Can SIL be shared between participants?
Yes. Participants living together may share support workers, and the NDIA sets each participant's ratio based on their needs and value for money.
Checked against the official sources on 2 October 2026. Rules change: confirm the current position with the agency before you rely on it.
Related terms
More in NDIS
Rostery handles this in practice
SCHADS interpretation, NDIS price-guide validation, claiming and the evidence an audit asks for — built for Australian providers.