What supported accommodation and SIL funding actually costs

Supported accommodation is one of the biggest, and most confusing, funding areas in the NDIS. Two different funding streams, SDA and SIL, sit underneath most arrangements, and the way they’re priced has almost nothing to do with a regular rental market. Understanding what actually drives the cost helps you ask the right questions before signing anything.

Two funding streams, two jobs

Specialist Disability Accommodation (SDA) funds the building itself: a home built or modified to a specific design category, because of the physical accessibility or specialist features it needs. Supported Independent Living (SIL) funds the support delivered inside that home, the staff who help with daily tasks, personal care, or overnight supervision. A participant can have SDA funding without SIL, SIL without SDA, or both together, depending on their situation. If you’re weighing this up for a young adult moving out of home for the first time, our guide on supported independent living for a young adult covers what families should look for beyond the funding structure alone.

This is general information rather than financial advice; your actual funding is determined by the NDIA based on your individual assessed needs, not a fixed rate card.

What actually moves the price

For SDA, the main cost drivers are the design category (from basic accessibility improvements through to fully specialised housing), the location, and how many other residents share the build. A newer, purpose-built home with high physical support features in a low-vacancy area of Supported Accommodation & SDA housing will sit at a different funding level than an older, modified group home.

For SIL, the cost is really a function of staffing intensity. A share house where two residents need light daytime prompting costs far less to staff than a home with one resident needing awake overnight support and two staff on hand during the day. The NDIA funds SIL based on a support ratio worked out from your functional capacity assessment, not a flat weekly figure.

What drives SDA and SIL costs

Factor	Pushes cost up	Pushes cost down
Design category	Fully specialised or high physical support	Basic or improved liveability
Staffing ratio	1:1 or overnight awake support	Shared support across several residents
Location	Low-vacancy, purpose-built stock	Existing, shared group homes
Support hours	24/7 rostered care	Daytime-only or drop-in support

What you still pay yourself

Even with full SDA and SIL funding in place, residents generally still contribute toward everyday living costs, rent, and a Reasonable Rent Contribution set against the base rate of the disability support pension. This surprises a lot of families who assume the NDIS covers everything once accommodation funding is approved. Ask any provider you’re considering to set out clearly, in writing, what’s covered by your plan and what you’ll be billed separately.

Questions worth asking before you sign

Ask how the provider calculates your support ratio and whether it’s reviewed as your needs change, not fixed for the life of the tenancy. Ask what happens financially if a housemate moves out and the shared support cost has to be redistributed. And ask directly what the total weekly out-of-pocket cost looks like once rent, contributions and any non-funded extras are added up, rather than relying on the funded figure alone.

Undisclosed or unexpected costs are one of the more common complaints raised about disability support services generally, so getting this in writing early is worth the slightly awkward conversation.

Getting the funding right in your plan

If you think your current SDA or SIL funding doesn’t match your actual support needs, that’s a conversation for a plan review, not something to just absorb. A support coordinator or plan manager can help you gather the evidence, usually updated assessments, to make the case for a change.

It’s also worth asking a prospective provider how often they revisit the support ratio once you’ve moved in. Needs shift, sometimes upward as a condition progresses, sometimes downward as someone builds independence, and a funding arrangement that was right on day one can quietly stop fitting a year later if nobody’s tracking it.

Comparing a handful of options rather than accepting the first house or provider offered tends to surface these cost differences early rather than after you’ve moved in. Our methodology explains how we assess and rank listings across the directory, and the homepage covers the full range of disability service categories in Perth if you’re weighing accommodation against other supports.

Getting the funding structure right at the start saves a difficult renegotiation later, so it’s worth the extra time before you commit to a house.