Heat Pump vs. AC + Gas Furnace in Houston: Which Costs Less to Run?

Published October 16, 2026 · Reviewed October 16, 2026

Part of our Heat Pump Installation & Replacement guides.

What is the difference between a heat pump and an AC with a gas furnace?

A heat pump is a single outdoor system that both cools and heats your home with electricity, while an AC with a gas furnace uses an electric air conditioner for cooling and a separate gas-burning furnace for heat. In summer, the two setups do the same job the same way: refrigerant absorbs heat inside the house and releases it outdoors.

The difference shows up only in heating mode. A heat pump runs its refrigerant cycle in reverse, pulling heat from outdoor air and moving it inside. ENERGY STAR describes the advantage simply: heat pumps move heat rather than converting it from fuel, and an air-source heat pump can deliver up to three times more heat energy than the electrical energy it consumes. A gas furnace burns natural gas to make heat and uses a blower to push it through the same ductwork the AC uses.

In Houston, choosing between a heat pump and an AC plus gas furnace is really a choice about how you want to pay for a few months of heating, because the cooling side is the same either way.

For a plain-language walkthrough of the refrigerant cycle, see how a heat pump works and why it fits Houston's climate.

Why does Houston's climate tilt the comparison?

Houston's climate tilts the comparison because cooling demand is about two and a half times heating demand, so heating cost is the smaller part of the yearly bill whichever system you choose. NOAA's 1991–2020 climate normals for Houston Intercontinental Airport (IAH) show 3,288 cooling degree days and 1,266 heating degree days a year.

Degree days are a standard way to measure how much heating or cooling a climate demands. Each day, the difference between the average outdoor temperature and 65°F counts toward cooling (when it is warmer) or heating (when it is cooler). A bigger number means more work for the system over a year.

Two things follow from Houston's numbers:

• Cooling efficiency usually matters most. Because cooling demand dominates, the cooling efficiency (SEER2) of whatever you install typically has a bigger effect on your annual HVAC energy use than the choice of heating fuel.
• Heating is mild but not zero. 1,266 heating degree days is enough to notice on a winter bill, and a few hard freezes each decade test any heating system. The heating fuel decision is real; it is just a smaller share of the total than it would be farther north.

How do you estimate heating cost with your own rates?

You estimate heating cost by working out how much heat your home needs over a typical winter, then pricing that heat through each system's efficiency at your own electricity and gas rates. The estimator below does that arithmetic for you using the NOAA IAH degree days and the rates you enter.

Here is the reasoning it follows, so you can check it:

1. Heat needed. Your home's heating need scales with heating degree days. Houston's 1,266 a year sets the size of the winter workload.
2. Heat pump cost. A heat pump's seasonal efficiency is expressed as HSPF2, the heat it delivers in Btu per watt-hour of electricity. Divide the heat needed by the HSPF2 rating to get the electricity used, then multiply by your rate in cents per kWh.
3. Gas furnace cost. A furnace's efficiency is expressed as AFUE, the share of the gas's energy that becomes heat in your home. One therm of natural gas contains 100,000 Btu. Divide the heat needed by AFUE and by 100,000 to get therms, then multiply by your price per therm. The furnace's blower also uses some electricity.
4. Compare. Because cooling runs the same way in both setups, the heating-season difference is the main operating-cost gap between them.

To use it, take the all-in rates from your own bills: total electricity charges divided by kWh used (including delivery charges, not just the energy rate on your retail plan), and total gas charges divided by therms used. Enter the HSPF2 and AFUE from the quotes you are comparing.

Heating cost per million BTU — your rates

Use the all-in prices from your own electric and gas bills (total charges ÷ usage).

Electricity (¢ per kWh)Natural gas ($ per therm)Heat pump HSPF2 (federal minimum 7.5)Furnace AFUE % (80% is a common minimum)

Enter both utility rates to compare.

The estimator does not assume any rate, efficiency or price on your behalf, and its output is an estimate for comparison, not a bill forecast. Houses with poor insulation, leaky ducts or unusual thermostat habits will land away from the estimate. Running it at two or three rate scenarios is a good way to see how sensitive the answer is.

How do a heat pump and an AC + gas furnace compare?

The two setups cool identically and differ in how they heat, how many pieces of equipment you maintain, and how they behave in a cold snap. The table summarizes the comparison for a Greater Houston home.

Heat pump vs. AC + gas furnace for Greater Houston homes

Factor	Heat pump	AC + gas furnace
Cooling	Same refrigerant cycle as a central AC	Same refrigerant cycle as a heat pump
Heating source	Moves outdoor heat indoors; electric backup heat strips for the coldest hours	Burns natural gas in a heat exchanger
Fuel	Electricity only	Electricity for cooling and the blower; natural gas for heat
Efficiency rating	SEER2 (cooling) and HSPF2 (heating)	SEER2 (AC) and AFUE (furnace)
Equipment count	One outdoor unit plus an indoor air handler	One outdoor unit plus an indoor furnace with a coil
Gas service needed	No	Yes, plus venting and combustion safety checks
Houston fit	Strong: heating demand is light and a single system runs year-round	Strong where gas service exists and the homeowner prefers combustion heat in freezes
Cold snaps	Capacity drops as it gets colder; backup heat strips raise electricity use	Full heat output regardless of outdoor temperature
Power outage	No heating or cooling without backup power	No heating or cooling without backup power; the furnace blower, igniter and controls need electricity
Refrigerant (new systems)	Lower-GWP refrigerant such as R-32 or R-454B	AC uses the same lower-GWP refrigerants; the furnace uses none
Federal minimums (Southeast)	14.3 SEER2 and 7.5 HSPF2 for split heat pumps	14.3 SEER2 for split AC under 45,000 Btu/h (13.8 at or above)

What can go wrong with each choice in Houston?

Each setup has a predictable weak spot: heat pumps lean on electric backup heat in hard freezes, and gas furnaces add combustion equipment that needs safety checks. Knowing those weak spots ahead of time keeps either choice from surprising you.

Heat pump risks

• Backup heat costs. On the coldest nights, electric resistance strips help the heat pump keep up. They are far less efficient than the heat pump itself, so a thermostat set to call for backup heat too easily can push a winter bill up. Ask how the backup heat is staged.
• Defrost cycles. In cold, damp weather the outdoor coil frosts and the system briefly reverses to clear it. That is normal, but it can feel like cool air from the vents. If it persists, read heat pump blowing cold air in heat mode.
• Year-round wear. A heat pump runs in both seasons, so maintenance matters twice a year. Our heat pump maintenance checklist for Houston covers what to check.

AC + gas furnace risks

• Combustion safety. A furnace's heat exchanger, venting and gas connections need regular inspection. EPA recommends having a trained professional inspect, clean and tune central heating systems annually and installing carbon monoxide alarms.
• Two systems aging separately. The AC and furnace often wear out at different times, which leads to the question of replacing one or both. Our guide to furnace repair vs. replacement covers that decision.
• Gas availability. Not every Greater Houston address has natural gas service. Confirm with your gas utility before assuming a furnace is an option.

Neither system heats or cools during a power outage without backup power, so outage planning is the same whichever you choose.

How can you check the numbers yourself?

You can check every input to this comparison from your own bills and the equipment specifications in a quote. Before you decide:

1. Pull a winter electric bill and a winter gas bill (if you have gas). Divide total charges by usage to get your all-in rate.
2. Read the efficiency ratings on each quote. Heat pumps list SEER2 and HSPF2; furnaces list AFUE; the AC paired with a furnace lists SEER2.
3. Confirm the pairing is certified. The AHRI Directory lists certified matched combinations of outdoor and indoor units by model number.
4. Ask how backup heat is set up on a heat pump quote, and how the furnace venting will be handled on a furnace quote.
5. Check incentives honestly. The federal Section 25C credit does not apply to property placed in service after December 31, 2025, so do not count on it for a 2026 installation. Utility programs change; ask your contractor which models qualify for any current program.

What should you do next?

Run the estimator with your own rates, then get firm quotes on both setups with model numbers and efficiency ratings so you are comparing like with like. If your current system is failing, our repair or replace decision framework helps you decide whether to replace now.

JHC Cooling & Heating installs and services Goodman heat pumps, air conditioners and furnaces across Greater Houston. You can request a quote on heat pump installation & replacement or heating installation & replacement, or call (832) 447-3233. Financing is available through FTL Finance, subject to credit approval.

Frequently Asked Questions

Is a heat pump cheaper to run than a gas furnace in Houston?

It depends on your electricity and gas rates and the efficiency of the equipment, which is why the estimator uses your own numbers. Houston's heating demand is light, about 1,266 heating degree days a year at IAH, so the heating-cost gap is usually small compared with cooling costs. Cooling costs are the same for both setups at the same SEER2.

Does a heat pump cool as well as a regular AC?

Yes. In cooling mode a heat pump uses the same refrigerant cycle as a central air conditioner. Cooling performance depends on capacity, SEER2 rating, sizing and ductwork, not on whether the unit can also heat.

Will a heat pump keep my house warm during a Houston freeze?

A properly sized heat pump with backup heat strips will keep a home warm in a typical Houston freeze. Heat pump capacity drops as outdoor temperature falls, so the backup strips carry more of the load on the coldest nights, which raises electricity use for those hours.

Does a gas furnace work during a power outage?

No. A modern gas furnace needs electricity for its blower, igniter and controls, so it stops during an outage just like a heat pump. Only a properly installed backup power source keeps either system running.

Can I get a federal tax credit for a heat pump in 2026?

No. The federal Section 25C credit does not apply to property placed in service after December 31, 2025. Financing through FTL Finance is available, subject to credit approval.

What efficiency ratings should I compare?

Compare SEER2 for cooling on both setups, HSPF2 for heat pump heating, and AFUE for a gas furnace. In the Southeast, federal minimums are 14.3 SEER2 and 7.5 HSPF2 for split heat pumps and 14.3 SEER2 for split air conditioners under 45,000 Btu/h.

Sources

1. NOAA NCEI — U.S. Climate Normals 1991–2020, Houston Intercontinental (USW00012960) — 3,288 cooling and 1,266 heating degree days a year (as of October 2026)
2. ENERGY STAR — Air-Source Heat Pumps — heat pumps move heat rather than converting it from fuel; up to three times more heat energy than electrical energy consumed (as of October 2026)
3. eCFR — 10 CFR 430.32, energy conservation standards — Southeast minimums: 14.3 SEER2 split AC under 45,000 Btu/h, 13.8 at or above; split heat pumps 14.3 SEER2 / 7.5 HSPF2 (as of October 2026)
4. U.S. EPA — Carbon Monoxide's Impact on Indoor Air Quality — annual professional inspection of central heating systems; CO alarms (as of October 2026)
5. Federal Register 2023-28500 — EPA Technology Transitions interim final rule (December 26, 2023) — transition of new residential systems to lower-GWP refrigerants (as of October 2026)
6. AHRI Directory of Certified Product Performance — certified matched indoor/outdoor combinations and ratings (as of October 2026)
7. IRS — FAQs for modification of sections 25C, 25D and others under Public Law 119-21 (FS-2025-05) — Section 25C not allowed for property placed in service after December 31, 2025 (as of October 2026)