What Is a Good SEER Rating? (2026 Buying Guide)

A good SEER rating for an air conditioner in 2026 is 16–18 SEER2 (approximately 16.7–18.8 old SEER). This range delivers 15–25% lower cooling costs than the federal minimum while keeping the upfront price increase reasonable — typically $800–$2,500 more than a base-model unit. For hot climates like Florida, Texas, or Arizona, stepping up to 18–22 SEER2 often makes financial sense due to longer cooling seasons.

The "right" SEER rating isn't universal. It depends on where you live, how much you pay for electricity, and how long you plan to own the home. This guide walks through the data so you can make a decision that actually pencils out for your situation.

SEER Ratings: What the Numbers Mean in Practice

SEER2 (Seasonal Energy Efficiency Ratio 2) measures how efficiently your air conditioner converts electricity into cooling over an entire season. Higher numbers mean less electricity for the same cooling output.

Think of it like miles per gallon for your car. A 13.4 SEER2 unit is your baseline economy car. An 18 SEER2 is a hybrid. A 24 SEER2 is a full electric vehicle. They all get you where you're going, but the fuel bill is very different.

Good to Know

SEER vs SEER2 note: Since January 2023, all new AC units use SEER2 ratings, which are roughly 4.7% lower than old SEER numbers due to tougher testing. When this guide references SEER ratings, we're using SEER2 — the number you'll see on the EnergyGuide label at the store.

SEER Rating Tiers: Categorizing Efficiency Levels

What SEER Rating Do You Need? (By Climate Zone)

Your climate is the single biggest factor in choosing the right SEER rating because it determines how many hours per year your AC runs. More running hours = more savings from efficiency.

Hot Climates (2,000–3,000+ Cooling Hours)

States: Florida, Texas, Louisiana, Mississippi, Alabama, Arizona, southern California, Nevada, Georgia, South Carolina

Recommended SEER2: 18–24+

In these states, your air conditioner runs 6–10 months per year. At 2,500 cooling hours and $0.16/kWh, a 3-ton system's annual cooling cost ranges from $480 at 20 SEER2 to $717 at 13.4 SEER2. That's a $237 annual difference — roughly $3,555 over 15 years.

The higher electricity rates in some of these states (Florida averages $0.16/kWh, Texas $0.14/kWh, California $0.32/kWh) amplify the savings further. In California, the same comparison jumps to $474 per year saved.

Mixed Climates (1,200–2,000 Cooling Hours)

States: North Carolina, Virginia, Tennessee, Kentucky, Maryland, Delaware, Oklahoma, Arkansas, Missouri, Kansas

Recommended SEER2: 16–20

You'll run your AC for a solid 4–7 months. The savings from high-efficiency units are meaningful but not as dramatic. At 1,500 cooling hours, the 13.4 vs 20 SEER2 difference is about $165/year for a 3-ton system at $0.16/kWh.

This is the zone where 16–18 SEER2 delivers the best bang for your buck. The upgrade from minimum to 16 SEER2 typically costs $800–$1,200 more and pays back in 7–10 years.

Cold Climates (600–1,200 Cooling Hours)

States: Minnesota, Wisconsin, Michigan, New York, Pennsylvania, Ohio, Massachusetts, Connecticut, Vermont, Maine, Montana

Recommended SEER2: 14.3–16

With only 2–4 months of meaningful cooling, ultra-high SEER2 units rarely pay back their premium during their lifespan. At 800 cooling hours, the annual savings from 13.4 to 20 SEER2 is only $88 — meaning a $3,000 upgrade takes 34 years to pay back.

Stick to the 14.3–16 SEER2 range and invest the savings in better insulation or a high-HSPF2 heat pump if you also heat with a heat pump.

Dry/Arid Climates (1,000–1,800 Cooling Hours)

States: Colorado, New Mexico, Utah, parts of Oregon and Washington

Recommended SEER2: 16–18

Despite hot summers, lower humidity and cooler nights limit total AC runtime. Mid-range efficiency is the best value here.

Cost-Benefit Analysis: Running the Numbers

Let's look at the total cost of ownership (purchase + 15-year energy costs) for a 3-ton AC at different SEER2 levels. Assumptions: 1,500 cooling hours, $0.16/kWh, 3% annual electricity rate increase.

Key Takeaway

In this scenario, 18 SEER2 has the lowest total cost of ownership. The 16 SEER2 unit is essentially tied. The premium 24 SEER2 unit actually costs more over 15 years because the energy savings don't offset the massive upfront price increase. This changes in hot climates with 2,500+ cooling hours, where 20+ SEER2 starts winning.

Electricity Rate Impact

Your local electricity rate dramatically affects which SEER rating makes sense. Here's how annual savings (13.4 vs 18 SEER2, 3-ton, 1,500 hours) vary by rate:

Pro Tip

If you pay more than $0.15/kWh, efficiency upgrades pay off faster. At $0.25/kWh (common in New England), the payback period for jumping from 13.4 to 18 SEER2 drops to about 6 years. At $0.10/kWh, it stretches to 14+ years.

Beyond SEER: Other Factors That Affect Efficiency

A SEER2 rating is measured in a lab. Your real-world efficiency depends on several additional factors:

Ductwork Condition

Leaky ducts waste 20–30% of conditioned air, according to ENERGY STAR. A 20 SEER2 system with leaky ducts may perform like a 14 SEER2 system with sealed ducts. Budget $500–$2,000 for duct sealing if your ducts are older than 15 years.

Proper Sizing

An oversized unit short-cycles — turning on and off frequently without completing a full cooling cycle. This wastes energy, increases wear, and dehumidifies poorly. Insist on a Manual J load calculation before any installation. It takes 1–2 hours and costs $100–$300, but it's the foundation of an efficient system.

Installation Quality

ACCA estimates that poor installation reduces efficiency by up to 30%. Key installation factors include proper refrigerant charge (within ±5% of manufacturer specs), correct airflow across the coil (typically 400 CFM per ton), proper line set sizing, and adequate clearance around the outdoor unit.

Thermostat Settings

A programmable or smart thermostat can save 10–15% on cooling costs by raising the setpoint when you're away or sleeping. The DOE recommends 78°F when home and 85°F when away for optimal savings without sacrificing comfort.

Insulation and Air Sealing

Your AC's workload depends on how well your home retains cool air. Adding attic insulation from R-19 to R-49 can reduce cooling loads by 10–15%. Air sealing around windows, doors, and penetrations can save another 5–10%.

What About Heat Pumps?

If you're considering a heat pump instead of a standard AC (and you should — heat pumps both cool and heat), the same SEER2 principles apply for cooling efficiency. Heat pumps carry an additional rating — HSPF2 — for heating efficiency.

High-efficiency heat pumps in the 18–22 SEER2 range with HSPF2 of 10+ can qualify for the $2,000 federal tax credit under the 25C provision, making them an even better deal than a standalone AC paired with a furnace.

SEER Rating Calculator

Compare energy costs for different SEER2 ratings based on your specific situation:

When Higher SEER Doesn't Make Sense

There are situations where investing in a higher SEER rating isn't the smart move:

You're selling the home soon. If you're moving in 1–3 years, buy the minimum or slightly above. You won't recoup the premium, and buyers don't pay proportionally more for high-SEER systems.

Your ductwork is in bad shape. Spending $3,000 extra on a 21 SEER2 unit while ignoring leaky ducts is like buying a fuel-efficient car and driving on flat tires. Fix the ducts first.

You're in a very cold climate. If your AC runs fewer than 800 hours per year, even aggressive efficiency upgrades struggle to pay back. Put that money toward heating efficiency instead.

Your electricity is very cheap. At $0.08–$0.10/kWh, the dollar savings from high SEER are modest. You might get a better return from other home improvements.