How Much Does AC Replacement Cost in Seattle? [2025 Data]

The average AC replacement cost in Seattle, Washington, is $7,377, but it commonly ranges from $5,098 to $9,785. The main cost factors for this project are the type, size, and efficiency of the AC unit, as well as labor. If you’re ready to invest in a new AC to keep cool through the Seattle summer, here’s what will impact the final price.

AC Replacement Cost Factors in Seattle

The specifics of your AC unit—including its type, size, and efficiency rating—will have a big impact on your overall costs. Here’s how.

Type of AC Unit

There are quite a few types of air conditioners on the market in Seattle, ranging from small units that cool a single room to whole-home cooling systems. As you might expect, these AC units come in a range of prices, too.

If you’re on a budget, you could consider a window AC unit, which starts around $150 and is suitable for apartments or vintage homes without ductwork (like a Seattle box house or a bungalow). For larger properties with existing air ducts, central AC would be a better option—but with prices starting at $2,500, it’s a much bigger investment.

Size of AC Unit

The size of your AC unit—which is measured in tons or British Thermal Units (BTUs)—also factors into your costs. You’ll pay more for larger AC units, which can cool more space than smaller models. For example, a 1.5-ton central AC unit could cost as little as $1,300, while the starting price for a 4-ton unit is double that.

To determine the best size AC unit for your Seattle home, you’ll need to conduct a Manual J calculation. This involves measuring your home’s square footage, evaluating the quality of your ductwork and insulation, and adding up the number of windows in your house. It’s a complex job, so it’s best to get help from an HVAC pro.

Energy Efficiency

Your AC unit’s energy efficiency—or how efficiently it uses electricity to cool your home—also affects your AC replacement costs. To understand how efficient a particular AC unit is, check its Seasonal Energy Efficiency Ratio (SEER) rating. New AC units should also have a SEER2 rating, which is an updated version of the SEER rating system.

The higher an AC unit’s SEER or SEER2 rating, the more energy-efficient it is. However, these higher-efficiency models also cost more than lower-efficiency units. In Seattle, the minimum SEER rating for new air conditioners is 14, while the minimum SEER2 rating is 13.4. 

Accessibility

An AC installer in Seattle, Washington, may charge higher rates if your part of your AC system is in a tight spot, on your roof, or in another hard-to-access location. In situations like these, the contractor often needs to spend more time and use additional equipment to pull out your old AC unit and install the new one—which can result in steeper labor prices.

AC Pro Costs in Seattle

When it comes to AC replacement costs in Seattle, the equipment is only one piece of the puzzle. You’ll also need to consider the price of labor, permits, taxes, and more.

Licensing and Certification

In Seattle, HVAC professionals must be licensed to “install, repair, or alter refrigeration or air conditioner equipment.” They should also be certified by the Environmental Protection Agency (EPA) to work with refrigerants. Before hiring someone to replace your AC in Seattle, make sure they have these qualifications.

Permits

AC replacement jobs in Seattle require a mechanical permit and a refrigeration permit. As a homeowner, you can pull the mechanical permit, but you’ll need a licensed refrigeration professional to obtain the refrigeration permit. Your permit fee will depend on a few factors, including the size of your AC unit and the value of the work.

Taxes

Seattle’s combined sales tax rate is 10.35%—the highest rate among major cities in the U.S., according to the Tax Foundation. Keep this in mind when you’re planning your AC replacement budget. If you choose a $3,500 central AC unit, you’ll pay just over $362 in sales tax on the purchase.

Rebates

If you install an air-source heat pump to serve as your home’s cooling system, you may qualify for a rebate from Seattle City Light. Discounts vary from $300 to $600, depending on the unit’s size and efficiency rating.

Does Replacing Your AC Increase Home Value in Seattle?

Since Seattle summers tend to be fairly comfortable weather-wise, there hasn’t always been a huge need for air conditioning in the Emerald City. (Just a couple of years ago, it was the least air-conditioned major metro area in the U.S., according to the Seattle Times.)

However, more homeowners here are installing AC—and now, a majority of Seattle-area households have air conditioning. For many homebuyers, having a working HVAC system (with cooling and heating) is an attractive prospect. In fact, a new HVAC system can increase your property’s value by 5% to 7%.

How Angi Gets Its Cost Data

Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We survey real Angi 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. 

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