Furnace Replacement Cost Calculator & Price Guide

Replacing a furnace typically costs $2,800 – $7,500 installed, and the average is near $4,800, based on Fixr. That includes the unit and professional installation, but it does not cover major ductwork changes or repairs to the rest of the heating system.

The price depends on the fuel the furnace burns, the size of your home, and the efficiency of the unit. The tables below break those factors down and show how repair compares with replacement.

Fuel type is the first thing that separates one quote from another. Natural gas is the most common fuel in many parts of the country, but homes without a gas line use electricity, propane, or oil. Each has different equipment, venting, and operating costs.

Electric furnaces are the least expensive to buy, but electricity is often the most costly way to produce heat, so the lower purchase price may be offset by higher monthly bills. Oil furnaces cost more up front and require a storage tank and chimney venting. Compare the installed price together with the expected running cost, not the installed price alone.

A furnace has to match the heating load of the home. Larger homes need units with a higher heat output, which raises the price of the equipment.

Size is a matter of load, not only square footage. Insulation, window quality, climate, ceiling height, and duct layout all change how much heat a home needs. A proper load calculation, not a rule of thumb, should determine the size. An oversized furnace turns on and off in short cycles, which wastes fuel and wears the equipment, and an undersized one will not keep up on cold days.

Labor is a separate part of the bill, and it can vary a lot. A simple swap of a unit in the same location with the same fuel and venting is the least expensive. Moving the furnace, converting to a different fuel, or fixing venting problems takes more time.

Installers may price by the job or by the hour. Ask which one applies and what the job includes, such as the thermostat, the gas line connection, the venting, and the permit.

Several items are not part of a basic replacement but show up on many invoices.

Ductwork is the largest one. If existing ducts are leaky, undersized, or badly designed, a new furnace will not perform as intended, and it may be worth fixing them while the system is open. Other possible extras include a new thermostat, a humidifier or air cleaner, a new gas line, and upgrades needed to meet current code.

Repair is the better choice when the problem is minor and the furnace is not near the end of its life. Igniters, sensors, blower motors, and thermostats are common repairs.

Age and repair frequency matter more than a single bill. If the furnace is old, repairs are becoming frequent, or a major component such as the heat exchanger has failed, replacement usually makes more sense than spending on a unit that is about to fail. Ask your technician for the age of the furnace and an honest estimate of the remaining life.

• Fuel type. Gas, electric, propane, and oil furnaces differ in both equipment and installation.
• Efficiency rating. Furnaces are rated by AFUE, which measures how much of the fuel becomes heat. Higher-efficiency units cost more up front and may save on fuel over time, which matters more in cold climates.
• Size and capacity. The unit must match the load of your home.
• Single-stage or variable-speed. Units with multiple stages or variable-speed blowers cost more and tend to run more quietly and evenly.
• Ductwork and venting. Changes to either add labor and materials.
• Brand and warranty. Equipment lines and warranty terms differ in price.
• Region and season. Labor rates vary, and prices and wait times may rise during the first cold snap.

The four sources in the first table are fairly close on the average, but their ranges differ. One source includes a broad guide that spans small electric units through high-end gas and oil systems, so its range is wider. Others may focus on a standard gas furnace in an average home. Differences in the cost of the unit, the labor rate, and whether ductwork, permits, and removal are counted may explain the rest.

When you read any figure, check the fuel type, the efficiency level, and whether it is the price of the equipment only or the full installed cost.

Furnace installation is not a DIY job for most homeowners. It involves gas lines, combustion, venting, and electrical connections. Errors can cause gas leaks or carbon monoxide hazards, which are life-safety risks. In many places, installation requires a licensed contractor and a permit, and an unlicensed installation can create problems with insurance or with the manufacturer's warranty.

Whichever contractor you pick, install carbon monoxide detectors on each level of the home.

Get at least three written quotes for the same type and size of furnace so that you are comparing like with like.

• Is a load calculation included, or is the size based on the old unit?
• What are the make, model, and AFUE rating of the proposed furnace?
• Does the price include removal of the old furnace, the thermostat, venting, and permits?
• What are the warranty terms on the equipment and on the labor?
• Are there any duct or code issues that could change the price?

Be careful with quotes that name a price without a site visit. A quote based on the old furnace's size alone can miss problems that surface on installation day.