The choice between ducted and split system air conditioning comes down to more than just upfront cost — it's about how many rooms you need to cool, whether you own or rent, and how long you plan to stay. Here's a frank comparison of what each system costs to install and run in Australia in 2026.
Upfront installation cost comparison
| System | Installation Cost | Best For |
|---|---|---|
| Split system (small, 2.5kW) | $1,200–$1,600 | 1 bedroom or small room |
| Split system (medium, 5kW) | $1,600–$2,200 | Living room or large bedroom |
| Split system (large, 7–9kW) | $2,000–$3,500 | Open plan living area |
| Multi-split (3 indoor units) | $4,500–$7,000 | 3 rooms from 1 outdoor unit |
| Ducted (2–3 bed home) | $8,000–$12,000 | Whole home, smaller footprint |
| Ducted (4–5 bed home) | $12,000–$18,000 | Whole home, larger footprint |
| Ducted with zoning | add $2,000–$4,000 | Control rooms independently |
The break-even point: when ducted is worth it
If you need to cool 4+ rooms, ducted becomes cost-competitive with multiple split systems. Three quality split systems (living + 2 bedrooms) cost $5,500–$8,500 installed — approaching ducted territory and covering only 3 zones. For a 4-bedroom home needing cooling in every room, ducted at $12,000–$15,000 is often cheaper than 5 individual split systems ($8,000–$15,000) and provides better whole-home coverage.
Split system wins when…
- You only need 1–3 rooms cooled
- Budget is under $5,000
- You rent or may move in the next 5 years
- Ceiling space is limited (ducted requires roof cavity)
- You want room-by-room control without ducted cost
Ducted wins when…
- You need 4+ rooms cooled
- Whole-home comfort is the priority
- Aesthetics matter (ducted is nearly invisible)
- You're building or doing a major renovation
- You want one system, one remote, one service
Frequently asked questions
Is ducted or split system air conditioning cheaper to install?
Split systems are cheaper per unit ($1,200–$3,500) vs ducted ($8,000–$18,000 for a full home). However if you need 4+ rooms cooled, multiple split systems can cost as much as ducted — and ducted provides better whole-home coverage.
Which is cheaper to run — ducted or split system?
A split system cooling one room is significantly cheaper to run than ducted cooling a whole home. However a ducted system with zoning, used only in the rooms you're in, can be comparable. The key is whether you'll use the whole-home coverage you're paying for.
Can I add more split systems later instead of going ducted now?
Yes — this is a common approach. Start with a split system in the main living area and master bedroom, then add more units over time. The disadvantage is cost per room is higher than ducted over 4+ rooms, and you end up with multiple outdoor units.
Does ducted air conditioning add more value than split systems?
Generally yes — ducted air conditioning is regarded as a premium feature in Australian property markets, particularly in Brisbane, Sydney and Melbourne. A ducted system is more likely to be specifically mentioned in property listings and can add $8,000–$20,000 to perceived property value depending on the market.