Ductless Mini-Split Cost Guide by Zone Count
What single-zone, dual-zone, and whole-home mini-splits actually cost installed — and when they beat central air.
Ductless mini-splits install one indoor unit per zone, connected by small refrigerant lines to an outdoor compressor. They're the right answer for additions, sunrooms, garages, and homes without existing ductwork. Installed costs run $3,500-$5,500 for a single zone to $14,000-$25,000 for a whole-home multi-zone system.
Cost by zone count
Single zone (one indoor head, 9-12k BTU): $3,500-$5,500 installed. Ideal for a single addition, sunroom, or workshop. Dual zone: $6,000-$9,500. Triple zone: $9,000-$13,500. Whole home (4-6 zones): $14,000-$25,000.
Per-zone cost actually drops as you add zones because one outdoor compressor serves multiple heads. But complexity grows — multi-zone systems require careful sizing and zoning logic.
When mini-splits beat central air
Homes without existing ductwork — adding ducts costs $4,000-$8,000 and loses 15-25% of efficiency to leakage. Mini-splits skip both costs. Additions where running ductwork is impractical. Rooms that are always too hot or too cold despite a central system.
Central air still wins on whole-house cooling cost per square foot in homes that already have good ductwork. Mini-splits also have visible indoor heads — a real aesthetic compromise some homeowners can't live with.