How much does a granny flat really cost?
Get an instant cost estimate tailored to your state, size, and build type. Based on real pricing data from Australian builders.
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1. Enter your location
Your postcode determines state regulations, approval pathway, and local cost adjustments.
2. Configure your build
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3. Get your estimate
See a detailed cost breakdown with approval pathway, timeline, and state-specific notes.
Typical granny flat costs in 2026
Based on our analysis of 10+ Australian builder websites. Prices are for site-built, standard finish, flat site.
Studio (25sqm)
$80k - $120k
$3,200 - $4,800 per sqm
1 Bedroom (40sqm)
$120k - $180k
$3,000 - $4,500 per sqm
2 Bedroom (60sqm)
$160k - $250k
Most popular size
3 Bedroom (80sqm)
$180k - $300k
Requires DA in most states
Transparent, research-backed estimates
We don't guess. Every cost figure is derived from published builder prices, state government fee schedules, and industry data.