What our analysis shows
Our calculations, data as of 23 October 2026
- Granny flat rules moved in three places in 2026. Victoria lifted its planning limit to 80 m² on 15 October, the ACT dropped its 500 m² minimum block on 1 July, and Tasmania put a 90 m² limit out for comment. Queensland's new Housing Code, from 1 September, adds a statewide building-siting figure that councils adopt by 2029.
- NSW, where fast-track granny flats began in 2009, is now the strictest mainland state for them. It has the smallest standard limit (60 m²) and the highest minimum lot for the fast route (450 m², against 300 m² in Victoria and none at all in WA).
- Falling out of the fast-track route adds weeks or months and, in our cost model, $3,000–$7,500 in fees and reports depending on the state, before any redesign the council asks for.
- Renting to anyone is now legal in every state and territory. Queensland was the last to drop its family-only rule, on 26 September 2022. Selling the flat separately is still not allowed anywhere.
Largest granny flat on the fast-track route, October 2026
- Queensland (Brisbane, Gold Coast)80 m²
- Victoria80 m² planning, 60 m² building*
- Western Australia70 m², any lot
- South Australia70 m², 2 bedrooms
- New South Wales60 m², lot 450 m²+
- Tasmania60 m² (90 m² proposed)
Our ranking by the floor area allowed without a discretionary council assessment. The ACT allows 90 m² but always needs a development application, so it is not ranked. *Victoria's Building Regulations are still to be amended to match the 80 m² planning limit.
What changed in 2026
Victoria's Amendment VC306 took effect on 15 October 2026. It raised the floor area of a small second dwelling from 60 to 80 m², stopped counting roofed decks and verandahs in that area, and dropped the separate access path requirement. Only the planning side has changed so far: the Building Regulations 2018 and Minister's Guideline 12 still describe a 60 m² dwelling and are to be amended "soon after". Until they are, design above 60 m² only after your building surveyor confirms they can issue the permit.
In the ACT, the missing middle reforms removed the 500 m² minimum block for a secondary residence from 1 July 2026; the 90 m² limit and the development application stay. Tasmania exhibited draft amendment 01/2026, which would lift the secondary residence limit from 60 to 90 m², until 22 July; the Tasmanian Planning Commission is assessing it, and 60 m² applies until the Minister decides. Queensland's Housing Code began on 1 September with a 50 m² siting figure for secondary dwellings (60 m² on lots of 1,000 m² or more), which councils take into their schemes over a transition to 2029.
State by state
New South Wales
Size: 60 m², or a larger limit if the council's LEP allows it (Housing SEPP 2021, s52).
Fast-track: Complying development certificate (CDC) from a council or private certifier, usually 10–20 days. Otherwise: Development application (DA) to council, needed for lots under 450 m², under 12 m frontage, heritage or flood-prone land.
- Lot of at least 450 m² and 12 m frontage for a CDC
- Site coverage 50% (lots 450–900 m²)
- Height 8.5 m
- Side setback 0.9 m, rear setback 3 m (lots 450–900 m²)
- One secondary dwelling per lot
Official source: NSW legislation: State Environmental Planning Policy (Housing) 2021.
Victoria
Size: 80 m² in the planning scheme since VC306 (15 Oct 2026; was 60 m² under VC253). The matching Building Regulations change is announced but not yet made, so check with your building surveyor before designing above 60 m²..
Fast-track: No planning permit for a small second dwelling on a lot over 300 m² in most residential zones without flood or environmental overlays; building permit still needed. Otherwise: Planning permit: VicSmart (10 business days) for lots under 300 m²; in bushfire or flood overlays a standard permit with referrals, often 6–12 weeks. Heritage, design and neighbourhood character overlays need no permit if the flat is no more than 5 m high and finished in muted tones.
- No gas connection
- No car space required
- Exempt from development and infrastructure contribution levies
- Cannot be subdivided off
Official source: Victorian Government: small second homes.
Queensland
Size: No statewide cap; each council sets its own: Brisbane 80 m², Gold Coast 80 m², Sunshine Coast 60 m², Logan 70–100 m², Ipswich 60–120 m², Moreton Bay 45–55 m².
Fast-track: Accepted development (no DA) in many council areas when the flat meets the planning scheme; building approval from a private certifier always needed. Otherwise: Development application where the flat exceeds the council cap or setbacks.
- Usually within 20 m of the main house (Brisbane)
- Infrastructure charges vary widely by council
Official source: Queensland Government: secondary dwellings providing housing solutions.
Western Australia
Size: 70 m² plot ratio area (R-Codes, from 10 April 2024).
Fast-track: No development approval for a compliant ancillary dwelling of up to 70 m² on any lot size; building permit still needed. Otherwise: Development approval where setbacks, open space or local planning policy are not met.
- Must meet R-Codes setbacks and open space
Official source: WA Planning: ancillary dwelling information sheet.
South Australia
Size: 70 m² and up to 2 bedrooms (raised from 60 m²; interim from 29 Feb 2024, adopted 18 Nov 2024); larger is a second dwelling, not ancillary accommodation.
Fast-track: Deemed-to-satisfy planning consent plus building consent; allow four to eight weeks in total. Otherwise: Performance-assessed planning consent where a standard is missed, 20–70 business days.
- Main dwelling's private open space stays accessible to all occupants
- SA Water augmentation charge for separate connections in Greater Adelaide
Official source: PlanSA: ancillary accommodation code amendment.
Tasmania
Size: 60 m² secondary residence under the State Planning Provisions; draft amendment SPP 01-2026 proposes 90 m².
Fast-track: No planning permit needed for the use in the General Residential zone when the design meets every acceptable solution (councils check this quickly); building permit needed. Otherwise: Discretionary planning permit where acceptable solutions are not met.
- Shares access and parking with the main dwelling
Official source: State Planning Office: SPP amendment 01/2026, secondary residences.
Australian Capital Territory
Size: 90 m² secondary residence; the 500 m² minimum block requirement was removed from 1 July 2026.
Fast-track: Development application through eDevelopment, then building approval. Otherwise: Development application (there is no permit-free pathway).
- No Crown lease variation needed (Planning Act changes passed 21 October 2026)
- Cannot be unit titled
Official source: ACT Government: missing middle housing reforms.
What fast-track does not cover
A compliant design can still be pushed into a full application by things on the land rather than in the plans. The ones that catch people most often:
- Sewer mains and easements. Building over or within about a metre of a sewer main needs the water authority's approval and sometimes an engineered solution or relocation, which can add $10,000–40,000. Ask for a sewer diagram before you pay for drawings.
- Bushfire. In NSW a CDC is not available in BAL-40 or the flame zone, and lower levels still require bushfire-rated construction that adds cost.
- Heritage and flood. Heritage items, conservation areas and flood-control lots fall outside the fast routes in most states.
- Covenants. A restriction on title can forbid a second dwelling even where planning allows it. It costs a few dollars to check the title first.
- Large-lot zones. In NSW the complying development route does not apply in the R5 Large Lot Residential zone.
Building rules everywhere
Planning rules decide whether a flat may be built; the National Construction Code decides how. Every granny flat is a Class 1a dwelling, so it needs a 7-star energy rating (BASIX in NSW), the liveable housing features the code now requires, such as step-free entry and wider doors, smoke alarms and, where it adjoins or sits close to another building, fire separation. These apply on every route, fast-track or not. If you plan to rent the flat, read our guides to land tax and capital gains tax as well.
Northern Territory
We do not price the Northern Territory, but its rules are worth knowing. The NT Planning Scheme calls a granny flat a dwelling-independent. Amendment 94, from 1 December 2023, raised the floor area allowed without planning approval on single-dwelling lots in urban zones from 50 to 75 m²; current scheme wording allows 100 m² in some rural and residential zones. Check the zone and clause for your lot with the NT planning office.
Timeline since 2009
| When | Where | What changed |
|---|---|---|
| 2009 | NSW | Granny flats first allowed as complying development (Affordable Rental Housing SEPP) |
| 26 Nov 2021 | NSW | Rules moved into the Housing SEPP 2021 |
| 26 Sep 2022 | QLD | Occupancy restriction removed: secondary dwellings can be rented to anyone |
| 14 Dec 2023 | VIC | VC253 introduces 'small second dwellings' of up to 60 m² |
| 29 Feb 2024 | SA | Interim change: ancillary accommodation can be self-contained, cap 70 m² |
| 10 Apr 2024 | WA | R-Codes reform: no minimum lot size and no development approval for compliant ancillary dwellings |
| 18 Nov 2024 | SA | Code amendment adopted by the Minister |
| 8 Sep 2025 | VIC | VC282 updates siting standards for lots under 300 m² |
| 10 Jun–22 Jul 2026 | TAS | Consultation on SPP amendment 01-2026 (90 m² proposal) |
| 1 Jul 2026 | ACT | Missing middle reforms remove the 500 m² block requirement |
| 15 Oct 2026 | VIC | VC306 lifts the planning limit to 80 m² |
| 21 Oct 2026 | ACT | Planning Act changes pass: automatic entitlement to a secondary residence on single-dwelling leases |
Checked against the planning instruments and government pages in October 2026. Rules change; your council or certifier has the final word on your lot.
This week's worked example
Week of 19 October 2026. A new example, rule and owner report every Monday.
A 55 m² two-bedroom flat with a budget finish on a flat block, services 15 m from the house, in Casey: our model puts it at $158,700 turnkey ($139,500–$177,500), or $2,890 per m². At the area's median 2-bedroom bond rent of $500 a week it would return 13.1% net and pay back in 10.2 years after tax.
Rule check: Tasmania's draft SPP amendment 01/2026 proposes lifting the secondary residence limit from 60 to 90 m²; it was on exhibition from 10 June to 22 July 2026.
From an owner (NSW, 2024): A heritage-listed family home cannot use the SEPP's complying development route for a granny flat; it has to go to council.