How long does a central AC unit last?

Most central AC units last 10-15 years with regular maintenance (annual tune-ups, filter changes). Units nearing or past this age that need a major repair are usually better candidates for replacement than repair.

What SEER2 rating should I choose?

Higher SEER2 ratings cost more upfront but lower monthly cooling costs. In hot climates with long cooling seasons, the higher-efficiency unit often pays for itself faster than in mild climates — a contractor can run the payback math for your specific region and usage.

Can I replace just the outdoor AC unit and keep the indoor coil?

It's possible but generally not recommended — mismatched indoor and outdoor components run less efficiently and may void manufacturer warranties. Most contractors recommend replacing the condenser and evaporator coil together as a matched system.

Does a new AC unit require duct modifications?

Not always, but if your existing ductwork was sized for a different tonnage or is leaking or damaged, a new unit's efficiency will suffer without duct repairs or modifications — a fact worth asking your contractor about before you sign a quote.

How Much Does It Cost to Replace an AC Unit?

Prices updated July 19, 2026

HomeRepairPrice Editorial Team

Replacing a central air conditioner costs $3,500 to $14,000 installed in 2026, with most homeowners paying an average of $5,975. The wide range comes down to unit size (tonnage), efficiency rating, and how much of your existing ductwork can be reused versus modified.

Cost by scope

2026 installed cost ranges

Item	Typical Cost	Notes
Straightforward AC-only swap	$3,000 – $7,500	Existing ductwork and furnace reused as-is
Full central/ductless system	$6,600 – $12,000	Includes larger scope or ductless multi-zone
Labor only	$500 – $2,500	Varies by access, electrical work needed

Cost by tonnage

AC units are sized in "tons" of cooling capacity, and larger homes need larger units:

1.5-2 ton (small homes, ~600-1,000 sq ft zones): lower end of the range
2.5-3 ton (average single-family homes): mid-range pricing
3.5-5 ton (larger homes): upper end of the range, before efficiency upcharges

An oversized or undersized unit both cost more to run and wear out faster — a proper Manual J load calculation from your contractor, not square footage alone, should determine tonnage.

Why AC prices are rising industry-wide

The ongoing transition to low-global-warming-potential refrigerants is adding roughly 5-10% to new AC equipment costs as manufacturers redesign compressors and coils around the new refrigerant standards — a trend affecting the whole industry, not just one brand or contractor.

Repair vs. full replacement

If your AC has a specific component failure — most commonly the compressor — rather than being broadly at end-of-life, repair can be far cheaper than replacement. See AC Compressor Replacement Cost: Repair or Replace? for the specific cost breakdown and the industry "50% rule" for deciding between the two. For the full-system view (furnace + AC together), see HVAC Replacement Cost: Full System Price Guide 2026.

Prices on this page are researched ranges compiled from multiple public contractor-pricing sources, not quotes from us or a guarantee of what you will pay. Actual costs vary by region, material choice, and job complexity — always get itemized quotes from licensed local contractors before committing to a project. See How We Price for our sourcing methodology.

Frequently Asked Questions

How long does a central AC unit last?: Most central AC units last 10-15 years with regular maintenance (annual tune-ups, filter changes). Units nearing or past this age that need a major repair are usually better candidates for replacement than repair.
What SEER2 rating should I choose?: Higher SEER2 ratings cost more upfront but lower monthly cooling costs. In hot climates with long cooling seasons, the higher-efficiency unit often pays for itself faster than in mild climates — a contractor can run the payback math for your specific region and usage.
Can I replace just the outdoor AC unit and keep the indoor coil?: It's possible but generally not recommended — mismatched indoor and outdoor components run less efficiently and may void manufacturer warranties. Most contractors recommend replacing the condenser and evaporator coil together as a matched system.
Does a new AC unit require duct modifications?: Not always, but if your existing ductwork was sized for a different tonnage or is leaking or damaged, a new unit's efficiency will suffer without duct repairs or modifications — a fact worth asking your contractor about before you sign a quote.

HomeRepairPrice Editorial Team

Our editorial team researches and cross-checks every price range against multiple contractor-facing sources (see our How We Price methodology) before publication. We are not a contracting company and do not sell leads, materials, or services.

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