Mini splits and central air both cool a home, but they take opposite approaches to distribution and control. The decision usually turns on the condition of your ductwork, how much you value room-by-room control, and your budget.
Efficiency and duct losses
Ductless systems tend to post higher efficiency numbers. Filterbuy reports that mini splits are commonly rated between 20 and 38 SEER2, while central air generally ranges from 14 to 21 SEER2. A large part of that gap is distribution. Filterbuy notes that central air systems lose 20% to 30% of their energy through leaks, holes, and poorly connected ducts, while mini splits have zero duct loss. Della makes the same point, that a ductless mini split avoids distribution losses through ducts, which matters most when ducts are leaky or run through a hot attic.
Zoning and control
Control is the other big divide. Della notes that mini splits allow separate temperature control by zone, while central air usually runs on one thermostat for the whole house. If different rooms have different comfort needs, or parts of the home sit empty during the day, per-zone control lets you avoid conditioning space nobody is using. A single-thermostat central system treats the whole house as one zone unless you add separate zoning equipment.
Installed cost
Cost depends heavily on ductwork. Filterbuy puts a single-zone mini split at $3,000 to $8,000, central air with existing ducts at $3,000 to $7,000, and central air that needs new ductwork at $7,000 to $15,000 or more. This Old House reports a total central air cost typically between $6,736 and $20,099 including installation, and ductless mini-split systems ranging from $1,500 to $8,000 depending on how many areas need cooling. The pattern is clear: if usable ducts already exist, central air is cost-competitive; if they do not, ductless usually avoids the biggest expense.
When central air still wins
Central air is not obsolete. Della advises choosing central air if your ducts are in good condition and you want hidden indoor equipment, one whole-home airflow system, and central filtration. A ducted system keeps all the equipment out of sight and filters the whole house through one system, which some homeowners prefer over visible wall or ceiling heads. The honest read is that good existing ducts tilt the decision toward central air, while missing or failing ducts tilt it toward ductless.
Frequently asked questions
Are mini splits more efficient than central air?
On paper, generally yes. Filterbuy rates mini splits between 20 and 38 SEER2 versus 14 to 21 SEER2 for central air, and notes central systems lose 20% to 30% of energy through ducts while mini splits have none.
Which is cheaper to install?
It depends on ducts. Filterbuy puts single-zone mini splits at $3,000 to $8,000 and central air with existing ducts at $3,000 to $7,000, but central air needing new ductwork jumps to $7,000 to $15,000 or more.
Can central air do room-by-room temperatures?
Not by default. Della notes central air usually uses one thermostat, while mini splits allow separate temperature control by zone. Central zoning is possible but requires added equipment.
When should I stick with central air?
Della recommends central air when your ducts are in good condition and you want hidden equipment, one whole-home airflow system, and central filtration.
How much does a ductless system cost overall?
This Old House reports ductless mini-split systems ranging from $1,500 to $8,000 depending on how many areas need cooling.