A natural gas vs electricity cost calculator compares the price of useful energy after accounting for local rates and appliance efficiency. For a quick estimate, U.S. households can start with about $1.50 per therm of natural gas and $0.17 per kWh of electricity, then replace those figures with current bill rates. The result depends heavily on the appliance, climate, and whether the comparison covers heating, water heating, cooking, or another use.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Residential natural gas | $0.80/therm | $1.50/therm | $3.00/therm | Illustrative delivered-rate range; local bills vary |
| Residential electricity | $0.10/kWh | $0.17/kWh | $0.35/kWh | Illustrative all-in rate range |
| Gas furnace heat | $10/MMBtu | $17/MMBtu | $33/MMBtu | At 80% annual efficiency, before fixed charges |
| Electric resistance heat | $29/MMBtu | $50/MMBtu | $103/MMBtu | At 100% point-of-use efficiency |
| Air-source heat pump heat | $9/MMBtu | $16/MMBtu | $34/MMBtu | At seasonal COP 3.0; climate affects performance |
What the calculator estimates for gas and electric use
The comparison starts with the amount of energy needed for the same task, not just the price printed on each utility bill. One therm contains about 100,000 Btu, while one kWh contains about 3,412 Btu. A gas appliance loses some fuel energy through exhaust or standby losses; electric resistance equipment converts nearly all incoming electricity to heat at the point of use. Heat pumps move heat and can deliver multiple units of heat per unit of electricity.
For a simple delivered-energy comparison, use this calculation: gas cost per useful MMBtu equals gas dollars per therm divided by therms per MMBtu, then divided by appliance efficiency. Electricity cost per useful MMBtu equals dollars per kWh multiplied by kWh per MMBtu, then divided by efficiency or heat-pump COP.
For example, at $1.50 per therm and an 80% gas furnace, useful heat costs about $18.75 per MMBtu. At $0.17 per kWh, electric resistance heat costs about $49.83 per MMBtu. A heat pump averaging a seasonal COP of 3.0 would cost about $16.61 per MMBtu at that electric rate. These are energy-only comparisons; fixed monthly service charges and equipment costs can change the household decision.
Assumptions: 1 therm equals 100,000 Btu, 1 MMBtu equals 1 million Btu, and stated utility prices are illustrative U.S. residential rates. Compare the cost per unit of useful output, rather than comparing a therm directly with a kWh.
Which line items change the gas-versus-electric quote
A calculator typically estimates operating expense, but a real household budget may also include the cost of connecting fuel, replacing equipment, and maintaining two utility accounts. Separate recurring charges from usage charges before comparing monthly bills. Taxes, delivery fees, fuel adjustments, and seasonal pricing may be included in a quoted rate or listed separately.
| Cost item | Natural gas range | Electric range | How to use it |
|---|---|---|---|
| Variable energy charge | $0.80-$3.00/therm | $0.10-$0.35/kWh | Enter the bill’s delivered rate, not a headline supply price |
| Monthly basic service | $8-$30/month | $10-$35/month | Count only charges that change under the scenario |
| Furnace replacement | $3,500-$8,500 installed | $4,000-$10,000 for a heat pump | Ranges depend on capacity, ductwork, and location |
| Gas line or electrical work | $500-$2,500 for a modest extension | $300-$2,000 for circuit or panel work | Major service upgrades can cost more |
| Inspection and permit | $50-$500 | $50-$500 | Local fees and required upgrades differ |
Installation prices are broad U.S. planning ranges, not a substitute for contractor bids. A gas conversion can require venting, combustion-air provisions, and a correctly sized gas line. An electric conversion may require a dedicated circuit, a larger breaker, or a panel upgrade. Keep one-time installation expenses separate from annual energy use to avoid a misleading payback estimate.
How gas rates, electric rates, and appliance efficiency shift totals
Utility rates can vary sharply between states and even between neighboring service territories. A household paying $0.11 per kWh faces a very different electric-heating result from one paying $0.30, while gas prices also rise and fall with distribution costs, supply conditions, and winter demand. Use the latest bill’s actual energy charge and delivery charge; if the bill separates them, add both before entering the rate.
Efficiency creates another major difference. A standard gas furnace may have an annual fuel utilization efficiency near 80%, while many newer models rate around 90%-97%. A heat pump’s seasonal coefficient of performance can be roughly 2.0-4.0, depending on model, outdoor temperatures, installation, and duct condition. Resistance heat has a COP near 1.0. For gas water heaters, compare annual energy use or recovery performance rather than assuming every unit turns fuel into hot water at the same rate.
Thresholds matter when estimating a specific home. A 60,000 Btu-per-hour furnace running at full input for 1,000 hours uses about 600 therms; at 80% efficiency, it provides about 48 MMBtu of useful heat. A 3-ton heat pump has a nominal capacity of about 36,000 Btu per hour, but its output and COP can drop in cold weather. If a home uses more than 1,000 therms annually for space heating, even a $0.50-per-therm rate change can alter annual fuel spending by roughly $500 before efficiency adjustments.
Assumptions: Equipment capacity is not the same as annual consumption; actual run time, weather, thermostat settings, and insulation determine usage. Efficiency and local marginal rates matter more than the appliance’s fuel label alone.
When heat pumps, gas furnaces, and resistance heaters cost less
At the illustrative average rates, a heat pump with a seasonal COP of 3.0 has a small operating-cost edge over an 80% gas furnace. At $0.17/kWh, it produces useful heat for about $16.61 per MMBtu, compared with $18.75 for gas at $1.50 per therm. The margin is narrow: a higher electricity rate or lower cold-weather COP can reverse it. A furnace operating at 95% efficiency would deliver heat for about $15.79 per MMBtu at the same gas price.
Electric resistance heat is usually more expensive for whole-home heating at typical U.S. rates. It can still make sense for a small, occasionally occupied space, where equipment cost and installation simplicity outweigh a higher cost per unit of heat. A heat pump water heater may use substantially less electricity than a resistance tank, but its purchase price, installation location, and local climate affect the total comparison.
Gas often has an advantage for high-temperature cooking or for homes with existing gas equipment and a low gas rate, but appliance-level savings can be modest compared with space heating. A household should compare annual usage attributable to that appliance, not divide the entire utility bill by the number of gas appliances. The lowest operating cost can differ from the lowest total cost once equipment, service charges, and expected years of use are included.
Three household examples show how annual costs compare
The examples below use illustrative rates of $1.50 per therm and $0.17 per kWh, before fixed charges. They show why the same rate comparison can lead to different results across home sizes and equipment. Actual consumption should come from bills, equipment labels, or an energy audit rather than from these sample amounts.
| Scenario | Energy use and assumptions | Estimated annual cost | Comparison |
|---|---|---|---|
| Gas furnace home | 600 therms, 80% AFUE | $900 gas usage | About 48 MMBtu useful heat |
| Resistance-heated home | 14,060 kWh, near 100% heat conversion | $2,390 electricity | About 48 MMBtu useful heat |
| Heat-pump home | 4,690 kWh, seasonal COP 3.0 | $797 electricity | About 48 MMBtu useful heat |
In this example, the heat pump uses less operating energy spending than the gas furnace, but the difference is only about $103 per year. A heat-pump installation costing several thousand dollars more than a furnace may take many years to recover through energy savings, unless incentives, cooling benefits, avoided gas charges, or larger heating demand improve the calculation. Conversely, if the home already has a suitable heat pump, the relevant decision may be whether to use it more often rather than replace equipment.
Annual figures should include both heating and cooling if a heat pump supplies both. For a fair comparison, assign gas use to the furnace and water heater separately where possible, and distinguish the electric base charge from the heating load. Example rates are not national averages guaranteed for a particular service area. Matched useful heat makes the equipment comparison clearer than a comparison of bills from different homes.
What regional rates and winter weather do to the estimate
Electricity costs tend to be lower in some parts of the Southeast and central U.S. and higher in many coastal and Northeastern markets, but local utilities can depart substantially from broad regional patterns. Natural gas availability and distribution charges also differ; some rural addresses lack a gas connection or pay more for propane, which is not priced like utility gas. Check the service address, not just a state-level average.
Cold-climate performance is important in the northern states and mountain regions. As outdoor temperatures fall, a heat pump may need more electricity to deliver the same heat and may use backup resistance strips. A seasonal COP of 3.0 is a reasonable illustrative assumption for some systems and climates, but a colder location may need a lower value; a mild climate may support a higher one. Gas furnace efficiency is comparatively stable across outdoor temperatures, although cycling and duct losses still affect delivered heat.
A simple sensitivity check can show whether the result is robust. Recalculate at electricity rates 20% below and above the bill rate, gas rates 20% below and above, and at two plausible heat-pump COP values, such as 2.2 and 3.5. If the favored option changes under small adjustments, the price difference is uncertain and equipment quotes or a professional load calculation may be more valuable than a precise-looking calculator result. Regional utility bills and local winter design temperatures should drive the estimate.
Gas connection fees, panel upgrades, and monthly charges
Existing infrastructure can decide the economics. A home with an active gas account may already pay a monthly customer charge even in months with little use; eliminating gas entirely could avoid that fee, but only if the account can be closed and no other gas appliance remains. Keeping a gas water heater or range often means retaining the connection charge, which should not be counted as a savings from switching only the furnace.
Conversely, a property without gas service may face a connection fee, meter work, trenching, and interior piping. A basic gas-line extension can fall around $500-$2,500, while long runs, road crossings, or difficult excavation can exceed that range. Electric conversion costs can rise if a 100-amp panel cannot support new loads or if a long circuit must be installed. Panel replacement commonly adds roughly $1,500-$4,000, with regional and code-related variation.
Permit requirements vary by city and county. HVAC replacements, new circuits, gas piping, and fuel conversions may require permits and inspections, often costing tens to several hundred dollars. Code upgrades—such as vent changes, shutoff valves, combustion-air improvements, or electrical protection—can add expense beyond the permit fee. Ask whether quotes include disposal of old equipment, line modifications, condensate drainage, and inspection corrections. Infrastructure changes can outweigh several years of projected fuel savings.
Reduce the gas-versus-electric bill without overbuying equipment
Use actual consumption to control the comparison. For heating, compare the cold-month increase over a mild-month baseline, or review utility usage history, rather than treating total annual gas use as furnace consumption. Check whether the utility bill lists therms and kWh separately from delivery charges. A calculator should use the marginal cost of additional energy when deciding how to operate existing equipment.
Before replacing a functioning system, request a repair estimate and compare it with a correctly sized replacement quote. A failed igniter, thermostat, or capacitor can cost far less than a full system change, while a cracked heat exchanger or repeated major repairs may justify replacement. Ask contractors to document the heating load and equipment capacity; oversized equipment can short-cycle and fail to deliver expected efficiency.
For replacement bids, compare the same scope and equipment tier. Obtain at least three itemized quotes that identify model numbers, efficiency ratings, labor, disposal, permit fees, duct or line work, and warranty terms. Avoid paying for a premium efficiency upgrade solely because its rating is higher: calculate projected annual savings at local rates and divide the price premium by those savings. Rebates and tax incentives may reduce the effective price, but eligibility and program funding change, so verify current rules before budgeting.
Low-cost measures can reduce both fuels’ consumption. Air sealing, insulation improvements, a correctly programmed thermostat, clean filters, and repaired duct leaks can cut the heat load before new equipment is sized. Reducing the home’s required heat often saves more reliably than choosing a more expensive fuel system based on one month of rates.
Build a useful calculator from the latest utility bills
Gather 12 months of gas and electric usage, current all-in variable rates, fixed monthly charges, and the efficiency or COP of the equipment being compared. If the bill’s rate changes by season or tier, use a weighted average for annual budgeting, or calculate each month separately. For a proposed fuel switch, estimate the usage that the new equipment would need to provide the same heating or hot-water service.
Include the full ownership comparison when equipment is changing. One approach is to add installation cost, annual energy expense, routine maintenance, and expected repairs over a chosen period, then subtract confirmed incentives. Do not assume that a future rebate or a particular fuel price is guaranteed. A five- or ten-year estimate is more informative when shown under low, middle, and high rate assumptions.
A calculator is most useful for screening choices, not guaranteeing a bill. It cannot automatically account for every home’s duct leakage, occupant behavior, local rate riders, fuel surcharges, or cold-weather backup operation. If two options appear close, use contractor load calculations and utility-specific rates before committing to equipment. Reliable inputs make a simple calculator more useful than a detailed estimate built on generic national prices.