Heat Pump vs. Natural Gas in the U.S.: How to Compare Bills

A U.S. homeowner cannot tell whether a heat pump will lower heating costs from one national electricity-to-gas price ratio. Utility territories, rate plans, seasons, gas-bill components, climate, home heat demand, and equipment design differ. Compare the actual services and charges for one home, then test how the result changes with plausible rates and system performance.

Start with the utility bills

Collect a full year of electricity and natural-gas statements. Note the billing units, delivery or distribution charges, customer fees, taxes, credits, seasonal rates, and any time-of-use or demand terms. If the gas meter also serves water heating, cooking, or a fireplace, separate those loads if possible. Do not assign the entire gas account to the furnace if some use will remain after a heat-pump conversion.

Estimate the heat delivered to rooms. For the furnace, account for seasonal efficiency and the fuel it consumes. For the heat pump, estimate seasonal electricity use under local weather and controls, including defrost and any resistance or furnace backup. A rated COP or product efficiency is a test metric, not a direct prediction of annual household use. Ask for a heat-loss-based design, equipment capacity, and the annual share of heat expected from each source. If a system is sized or controlled poorly, backup use and operating cost can differ substantially from an estimate.

Compare variable energy charges on the utility’s actual schedule. Some residential plans have seasonal or time-varying rates; some offer special electric-heating options. The heat pump’s load occurs mostly during heating weather, so applying a summer or annual average rate to every winter kWh can mislead. DOE guidance emphasizes the relationship between load shape and bill structure. Use utility calculators and tariff sheets for the household’s rate class and service area.

Count charges that change and those that stay

Separate the cost of each fuel’s units from fixed account charges. If the household retains gas for another appliance or for hybrid backup, a gas customer charge or delivery component may continue. If gas service ends, verify with the utility which charges stop and whether disconnection or reconnection fees apply. Electricity fixed charges often remain regardless of heating technology. Count as savings only charges that actually change because of the project.

The same distinction applies to project costs. Keep annual operating costs separate from equipment and installation quotes, electrical work, duct or distribution changes, maintenance, financing, and confirmed incentives. Compare options that meet the same home heating needs and state whether cooling or hot-water service is included. If the project adds a service such as air conditioning, show it as a separate benefit instead of treating it as free heat-pump savings.

Interpret regional models cautiously

ACEEE’s corrected April 2025 report models bills for detached homes in selected utility regions in Minnesota, Colorado, Maine, and Connecticut. It uses then-current utility rates and specific heat-pump and envelope scenarios. In the studied cases, modeled bill outcomes differ by prior fuel and region, and rate designs or weatherization can change the result. The model illustrates why local rates matter; it is not a measured result for a particular household, a current rate lookup, or a national forecast. Its selected states and home types do not represent every U.S. utility or housing stock.

Use that kind of study to ask better questions about rate structure, envelope improvements, and system efficiency. Replace its prices and assumptions with the household’s current bill, a local design estimate, and the utility’s current tariff. If the conclusion changes across reasonable rates or backup shares, report the result as sensitive. No single regional result should be copied into a homeowner’s calculator as expected savings.

Keep Massachusetts program examples in scope

Mass Save currently describes a seasonal heat-pump electricity rate for use from November 1, 2026 through April 30, 2027. Its calculator says to estimate the customer’s rate by subtracting 7 cents per kWh for Eversource or Unitil customers, or 4 cents for National Grid customers; the result is customer-specific and the calculator is an initial estimate. These are dated program inputs, not universal Massachusetts rates or a guaranteed bill reduction. Check the page again for the applicable period, utility, and customer terms.

Mass Save also lists maximum integrated-control switchover temperatures for partial-home rebate eligibility: at or below 30°F for oil or natural gas and at or below 5°F for propane, based on average fuel costs from 2019–2021. Those are rebate limits, not current economic recommendations. The program explains that the gas threshold is intended to support emissions reduction, not to establish operational savings. A household’s cost-oriented control point depends on current local prices, equipment performance at outdoor temperatures, and the home’s design.

Make the next estimate auditable

Ask the installer to show estimated annual electricity and gas use, seasonal performance assumptions, backup or switchover settings, the utility rate used, and which fixed charges are included. Compare the same service and weather basis, then make low, central, and high cases for heat demand, rates, and backup. Keep a copy of the source tariff and date. Recheck local program eligibility before counting an incentive. For a broader method to convert billed fuels to useful heat, see the cross-fuel guide; for simple payback boundaries, see the calculator assumptions guide.