How Much Does a Boiler Replacement Cost in 2025?

Boiler Replacement Cost Factors

Replacing a standard gas boiler costs about $5,000, and a high-efficiency model costs about $7,500. These figures depend on the boiler type, size, brand, and other factors.

Type

While a replacement boiler may cost between $3,605 and $8,444, different boiler systems have respective averages within this range. Depending on the system type, boilers can heat your home, water, or both. The system design determines how the boiler heats, distributes, and stores water or steam.

Standard Boiler

A standard boiler averages $3,000 to $7,000. Also called conventional boilers, standard boilers rapidly heat water in the pipes that run through the tank, then send hot water to taps as necessary. These systems are popular in larger homes and buildings, floor heating systems, and various large-scale functions.

Combination Boiler 

A combination boiler costs $6,000 to $10,000. These compact, wall-mounted units don’t have storage tanks, allowing them to deliver central heating and on-demand hot water with a minimal footprint. However, because they have limited heating capacity, combination boilers are best reserved for small spaces.

System Boiler 

System boilers range from $3,000 to $6,000. Also called sealed systems, they feature a closed loop that keeps water contained, enabling more consistent pressure and efficiency.

High-Efficiency Boiler

High-efficiency boilers cost between $6,000 and $11,000 for installation. These units usually save 10% to 20% on energy bills. High-efficiency boilers have an Annual Fuel Utilization Efficiency (AFUE) of 90+, meaning that the boilers convert more than 90% of the fuel into heating. Most high-efficiency boilers are tankless, but some need a hot water storage tank.

Steam vs. Hot Water Boiler

Steam and hot water technologies refer to how a boiler heats and circulates water. Steam boilers cost between $3,500 and $9,000, while hot water boilers range from $1,200 to $8,000. Steam carries and transfers heat more effectively and quickly than other systems, making it an advantageous option for colder climates and or limited insulation.

In comparison, hot water boilers heat water to a specified temperature and circulate it through the pipes to radiators, baseboards, and other heating systems. Because hot water boilers operate at lower temperatures than steam boilers, they’re generally more energy-efficient in most climates.

Condensing vs. Non-Condensing

Condensing and non-condensing are design characteristics determining the energy efficiency and exhaust management of various boiler systems.

Condensing boilers, ranging from $1,900 to $7,000, capture and reuse heat from combustion waste. This process enables high efficiency, often over 90% and sometimes up to 99%. Non-condensing units cost $1,200 to $5,000 and don’t recover heat from flue gases, instead venting it outdoors. Units with non-condensing technology offer less efficiency than condensing options, between 80% and 89%

Boiler Size

Matching your boiler with your home’s heating load ensures optimal efficiency and performance. The size of your home directly impacts the necessary size (or power) of your boiler.

A boiler’s size generally refers to its heating capacity, measured in either British Thermal Units (BTUs) or kilowatts (kW). Higher BTU and kW ratings correspond to higher energy production and overall replacement costs.

Other factors may also influence your home’s heating demand and boiler size requirements, such as the age of your home, local climate, insulation quality, and the number of doors and windows. For example, see how climate zones impact typical heating capacity ratings:

• Year-round humidity and heat: 18–35 BTUs per sq. ft.

• Moderate heat and mild winters: 25–40 BTUs per sq. ft.

• Moderate heat and cold winters: 35–50 BTUs per sq. ft.

• Constantly frigid temperatures: 40–60 BTUs per sq. ft.

BTUs don’t have a single unit cost, but your home’s size, local climate, and other factors can help identify a cost range.

Boiler Brand

A brand doesn’t necessarily affect technological specifications for a boiler, but its reputation for engineering and build quality, warranty offerings, and customer service may correlate with higher costs.

For instance, premium brands typically offer superior energy efficiency, customer support, longevity, and other benefits over budget-friendly options. Affordable brands have lower upfront costs, sometimes 10% to 20% lower than premium units, but still offer key features and conveniences.

Labor

A significant portion of your budget goes toward labor, about $1,500 to $5,000 to hire a local boiler installer. These HVAC professionals charge $75 to $200 per hour. Some may offer a flat rate instead of hourly based on their assessment. These costs account for replacing the existing boiler unit and installing its exhaust, flue or flue pipe, drain, and fuel line.

Removal and Disposal

Expect to pay between $200 and $500 to remove and dispose of an old boiler. The cost depends on the accessibility of the boiler, fuel type, and size. Units that weigh over 200 pounds or units in hard-to-reach areas cost more.

Changing Boiler Types

Gas boilers are the most common and efficient on the market, and many homeowners with access to a gas main opt to switch. Depending on your current heating setup, connection, and ventilation, costs to switch your boiler type to oil, propane, electric, or gas may include:

• Gas line hookup: $500–$2,000

• Gas line installation: $2,500

• Chimney Liner: $1,500–$4,000

• Old tank removal: $500–$3,500

• New oil tank installation: $1,600–$6,000

• New natural gas to propane conversion kit: $150–$500

• New propane tank installation: $1,700–$4,300

• Electrical upgrades: $1,200–$2,000

Boiler Costs by Fuel Type

Boilers cost anywhere from $3,000 to $16,000, but prices vary by fuel type. These figures account for upfront installation costs, but fuel type can also impact long-term fuel supplies, maintenance, and repairs costs.

Oil Boilers 

Oil boilers cost $4,800 to $9,000. Fueling with oil continues to become more costly, and installing oil appliances in your home may require installing an oil tank. These units can be high maintenance but run at a higher temperature than other boilers and offer similarly increased efficiency.

Oil boiler replacements are most common in old homes with pre-existing oil tank installations, areas where gas is less accessible, or where other fuel types are less economical.

Propane Boiler

A propane boiler replacement costs between $2,800 and $7,500. While propane is more costly than natural gas, it burns more efficiently. Installing a new propane tank costs between $1,700 and $4,300, while renting a tank costs between $50 and $200 per year.

Gas Boiler 

Gas boiler replacements usually cost $4,000 to $10,000. A gas boiler requires a gas line for your home and needs access to plumbing and vents. High-efficiency units also need access to a condensation drain.

Electric Boiler 

Electric boilers are the least expensive to replace than other types, starting from $1,800, but some models can cost $8,000 or more. While they operate efficiently and with minimal energy waste, converting almost all the electricity into heat, they’re slow to do so. They’re most cost-effective for homes with limited square footage or located in moderate climates.

Outdoor Wood Boiler

Outdoor wood boilers cost $7,000 to $16,000. These systems are typically reserved for rural homes with limited grid or utility access. If wood suitable for burning is free or inexpensive, outdoor wood boilers can offer high heat with low operating costs.

Boiler Replacement vs. Repair

Deciding between repair or replacement comes down to what’s most advantageous and cost-effective long term. Boiler repairs cost between $200 and $600, although some can cost $1,000 or more. In comparison, a replacement may cost 10 times as much. Opting for minor repairs is usually the preferred option, especially if your system is in good condition and only a few years old.

If your boiler is older than 12 to 15 years, consider replacement. Boilers become less efficient and more prone to breakdowns as they approach the end of their expected lifespans, and these costs can sometimes compete with the expense of a replacement. Replacement is also an opportunity to upgrade or switch to a model that offers superior fuel efficiency.

Does Replacing a Boiler Increase Home Value?

Replacing your boiler is one of the best investments you can make, yielding one of the best returns among other property improvement projects. Besides appealing more to potential homebuyers, new boiler models provide higher efficiency and reliability. The total return on investment depends on numerous factors. However, boiler replacements in areas where homes more commonly rely on them, such as in the northeastern U.S., typically earn relatively high ROIs. 

Budgeting for a Boiler Replacement

Replacing a boiler is a significant investment, but there are several ways to streamline costs without compromising safety, quality, or efficiency. Try these tips:

• Research tax incentives and rebates for energy-efficient appliance replacements to offset upfront costs.

• Choose a boiler model sized properly for your home to maximize efficiency and minimize wear.

• Bundle with other HVAC services, such as ductwork cleaning or AC repair.

• Get detailed estimates from contractors to closely compare services.

How HomeAdvisor Gets Its Cost Data

No place is more important than your home, which is why HomeAdvisor connects homeowners with local pros to transform their houses into homes they love. To help homeowners prepare for their next project, HomeAdvisor provides readers with accurate cost data and follows strict editorial guidelines. We surveyed thousands of real customers about their project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects.