Short answer: Most San Antonio homeowners spend $6,500 to $16,500 for a full AC system replacement in 2026, installed. Ductless mini-split systems start around $3,500. The biggest variables are tonnage (size), SEER2 efficiency, whether the furnace/air handler is replaced at the same time, and whether new ductwork or electrical work is needed.
What a "full AC replacement" actually includes
When we quote a full system replacement in San Antonio, the price almost always covers:
- The outdoor condenser (compressor unit)
- The matching indoor evaporator coil
- A new furnace or air handler (recommended — mismatched ages cause efficiency loss)
- New refrigerant line set or flush of existing lines
- New thermostat
- New disconnect, whip, and pad
- Permit, code-required updates, and city inspection
- Full system commissioning (proper refrigerant charge, airflow setup, static pressure test)
- Labor warranty (we offer 10 years on parts and 2 years on labor)
If a quote leaves any of those out, the headline price is misleading.
2026 price ranges by system size
Texas heat means most San Antonio homes need 2.5–5 tons of cooling.
| Home size | Typical tonnage | Installed price range (14.3 SEER2) |
|---|---|---|
| Under 1,400 sq ft | 2 ton | $6,500 – $9,500 |
| 1,400 – 1,800 sq ft | 2.5 – 3 ton | $8,500 – $12,000 |
| 1,800 – 2,400 sq ft | 3.5 – 4 ton | $11,000 – $14,500 |
| 2,400+ sq ft | 4 – 5 ton | $13,000 – $16,500 |
Upgrading from base efficiency (14.3 SEER2) to a high-efficiency variable-speed system (17–20+ SEER2) typically adds $2,500 – $5,000 but cuts summer cooling bills 20–35%.
Ductless mini-split pricing
If you're cooling a garage, casita, addition, sunroom, or a single problem room, a ductless mini-split is usually the right call. Pricing starts around $3,500 installed for a single-zone system and goes up from there based on capacity and the number of zones:
- Single-zone (one indoor head) — starting around $3,500
- Multi-zone (2–4 indoor heads) — typically $6,000 – $12,000+
- Whole-home ductless — priced like a full replacement, depends on number of zones and capacity
Mini-splits are also a great fit for older San Antonio homes without existing ductwork.
What drives the price up or down
- SEER2 rating. As of 2023, every new system in Texas must be at least 14.3 SEER2. Higher SEER = better efficiency, longer warranty, higher upfront cost.
- Single-stage vs. variable-speed. Variable-speed systems run longer on low — better humidity control in San Antonio's humid summers and quieter operation.
- Ductwork. Old, leaky, or undersized duct systems can lose 20–30% of your cooling. Sometimes a partial reseal is enough; other times we recommend duct redesign.
- Electrical and gas line updates. Older homes (especially in Alamo Heights, Olmos Park, and Beacon Hill) often need a panel breaker swap or a new disconnect.
- Indoor air quality add-ons. Whole-home media filters, UV lights, and fresh-air ventilators each add $400 – $1,800.
- Brand and warranty. Higher-tier brands (Trane, Carrier, Lennox) typically run 10–20% more than value brands but carry stronger compressor warranties.
Should you repair or replace?
We wrote a full guide on that decision — AC Repair vs. Replace. The 30-second version: if your system is over 10 years old and the repair quote is more than 40% of replacement cost, replacement almost always wins on a 5-year math basis, especially with the efficiency gains.
Financing in San Antonio
Most replacements at this price point are financed. We offer 0% APR options for qualified buyers, plus longer-term low-rate plans. See AC replacement financing for current programs.
How to get an accurate quote
You have two good options with Carnes and Sons:
- Quick phone or online estimate. Tell us your home size, system age, and what's currently installed, and we'll give you a realistic ballpark price range the same day. Great for budgeting and comparing options before you commit to a visit.
- Free in-home quote. For a firm, written number, one of our techs comes out, measures the home, looks at your existing equipment, ducts, electrical, and where the air handler lives, then prices the job on the spot. No obligation, no high-pressure sales.
Either way, the final installed price is locked in writing before any work begins — no surprise add-ons. Book a free replacement quote or call us and we'll cover San Antonio, Schertz, Cibolo, Boerne, New Braunfels, and surrounding Hill Country.
FAQ
How long does an AC last in San Antonio? Most properly maintained systems last 12–15 years here. Heat, humidity, and dust shorten lifespan vs. milder climates.
How long does installation take? A standard same-day system swap is 6–8 hours. Adding ductwork or a furnace can push it to 1.5–2 days.
Do I have to replace the furnace too? Not legally — but mixing a brand-new condenser with a 15-year-old furnace usually voids the new system's warranty and tanks efficiency. Plan for both.
How much is a mini-split in San Antonio? Single-zone ductless mini-splits start around $3,500 installed. Multi-zone systems for several rooms typically run $6,000–$12,000+ depending on capacity and number of indoor heads.
Are there 2026 rebates? CPS Energy regularly offers rebates on high-efficiency systems. We file the paperwork for you and apply the rebate to your invoice.