Whole House Generator Cost & Consumer Guide

Kenneth Wilson

Have you ever thought about what you’d be doing in the event of a power failure at home?

Sure, it’s easy to wait for a couple of minutes hoping for electricity to be back– but what if it goes on for an extended period? Picture this: your home in total darkness for hours, or maybe even days. No appliances, no light, no electronics– power outages can be a very uncomfortable (and borderline traumatic) experience for many homeowners. It would be twice as agonizing during severe weather storms or in the event of natural disasters.

With that in mind, it’s crucial to have an alternate power source at home. A whole house generator can make your household emergency-proof, as these machines are automatically switched on once the power goes out.

But what will it cost?

You can expect a whole-house generator to cost about $4,350 on average. Such is the price tag you need to make to provide backup power to the entire house.

A more general estimate for medium-sized homes is at $12,500 to $27,300 upfront. The total costs will have an additional $185 to $500 in annual generator maintenance and upkeep. Although the costs may appear expensive to several homeowners, more families realize the benefits of having a whole house generator at home. If you live in an area with frequent outages and severe weather conditions, it’s a necessary machine to ensure your comfort 24/7.

Chart showing the cost of a whole house generator installed from portable / standby to 5000 sqft or more home

Given that one unit may go up into the tens of thousands, many homeowners remain unsure if it is truly an excellent investment to make. Generators also range in type, size, and function– so the choice can get confusing.

Fret not, we’re here to discuss everything about whole house generator costs, and we’ll cover some essential points you need to know. This guide will help you determine the right generator for your home power backup needs.

Why Buy a Whole House Generator?

A whole house generator is connected to your home’s electrical wiring system. As soon as it detects a power outage, it will provide your household with sufficient backup power, at least until the electricity comes back. Though it sounds like one essential machine at home– it can be rather expensive at a thousand dollars minimum. There are also other maintenance costs in keeping a whole house generator at home.

The installation of a whole house generator also needs to be left to a professional generator technician. These specialists can closely monitor your generator units, such as oil or filter changing and other routine upkeep services. Doing so will extend the lifespan of your whole house generator.

In case you’re wondering if it will be a good investment– Remodeling Magazine reported that your property would get an average of 150% Return on Investment (ROI) after installing a whole house generator. For example, a generator worth $15,000 will add $9,000 more value to your home. So consider it an excellent long-term investment for your property.

Generators: Cost Per Scale

The big question goes, what kind of generator can I buy on my budget? That depends on several factors, including brand, fuel source, size, and generator type.

Regardless, there will be an ideal generator to meet all your backup power needs. So, let’s take a closer look at the options you can expect at different price points.

  • $10,000: Nowadays, you can expect to buy a large portable generator or a regular-sized standby unit at the $10,000 price point. These are already enough to power several of your appliances and circuits. However, the installation costs may add a few hundred dollars to the total expenses. It would be better to shell out a bit more for a capable portable generator, though.
  • $15,000: With a $15,000 budget, you can expect to install a more powerful standby generator for your home. If you include the installation expenses, the capacity of your new generator can go up to 22 KW within this budget range. These units can handle loads of a typical 3,000 to 5,000 square foot home. If you live in an area with frequent power outages, such as the East Coast, this generator will make your life a breeze.
  • $20,000: A $20,00 budget will ensure you have a standard whole house generator with enough capacity to power a traditional 5,000 square foot household. It means you can use at least two major home appliances and several circuits simultaneously. In addition, it will give you a more convenient living experience, especially in times of extended power outage.
  • $25,000: Since a whole house generator can be a hefty investment, you can get the most bang out of your buck with a $25,000 budget. It will give you an advanced, state-of-the-art unit that can efficiently provide backup power to homes larger than 5,000 square feet.

Some units have a power capacity of up to 40 KW, allowing you to use multiple appliances in almost the same manner you use standard electricity. So you might not even notice there’s a power outage going on.

Factors Affecting Whole House Generator Cost

Keep in mind that there will be several factors that can either increase or decrease your whole house generator expenses. No one prize fits all as your home’s generator needs will be unique.

For your reference, let’s discuss the factors in detail.

What impacts the cost of whole house generator.

Cost of Generator

In selecting a whole house generator, you will need to consider the upfront costs of the generator unit itself. You will also choose from two primary generator types: portable or standby.

  • Portable Generator - A high-quality portable generator will cost you somewhere between $1,300 to $3,700.Although these units cannot provide backup power for your entire household, they can still offer you sufficient emergency power for a few necessary appliances during unwanted power outages– such as those caused by hurricanes or severe storms. With their portable design, you can quickly move them from one area to another. The convenience makes for a great selling point among many homeowners. Portable generators are commonly run on diesel, gas, or liquid propane. Therefore, it is ideal to stock up on these fuel sources to refill your portable generator regularly.
  • Standby Generator - Standby generators greatly vary in size, so you can expect to shell out $2,500 to $20,000 for a top-quality unit on average. The size of your chosen standby unit will define its backup power capacity. Smaller units can power several small appliances, such as an AC unit or refrigerator. Meanwhile, larger units may be able to provide power for your entire household. Since these generators are installed permanently, one downside is that you will not move them around at ease.

Capacity (Wattage)

Another determining factor on the price of your whole house generator is its power capacity or wattage. It would be best to determine the answers to questions such as, how much power you need for your essential appliances? The unit’s kilowatts (kW) capacity will heavily influence the cost of your whole home generator.

Popular generator sizes for home use are available in different varieties, such as 11, 16, and 20 kW generator units. If you’re uncertain about the ideal generator capacity for your home’s power needs, talk to an electrician to avoid wasting money in buying the wrong generator.

Generator Type

Portable generators are an efficient choice for homeowners wanting to save some money as they do not have recurring heavy maintenance costs. Since you can move them anywhere around your house, they will be more durable and easier to operate.

Meanwhile, a standby generator will generally cost you more. In addition, you will need the services of an electrician to have your unit installed correctly into the electrical panels and its fuel source. Expect additional fees for local permits and necessary site preparation as well. Aside from the two main generator types (portable and standby), inverter units are becoming another popular generator type for residential use. These generators work similar to portable generators– but they are connected to an inverter instead. As a result, the system takes in DC only to change it back to AC.

This choice is great for homeowners looking for energy-efficient solutions, as the generator provides clean energy. Some units also come in a portable design for that added convenience.

Installation Costs

Opting for a standby generator will cost you around $4,560 on average, including assembly-relevant permits and wiring work.

In some cases, you may need to dig a tank for your generator unit. Some areas may require a special permit for tank digging and installation– which may add to the total tab. Electrical lines may also need to be extended for your generator to run efficiently. Accordingly, your installation costs will be higher if your home is far away from fuel lines to ensure having safe ventilation and exhaust ducts.

Another defining factor that may affect your whole house generator installation costs includes nearby access to natural gas lines. If you live in an area without underground pipes, you will have to go with generators running on liquid propane.

Fuel Source

Your generator’s fuel source may also influence your whole house generator expenses. These units need a consistent supply of fuel to provide power. If you have a portable generator, you will commonly need diesel, liquid propane, or gas as a fuel source. In contrast, standby generators are permanently installed– so it needs a dedicated natural gas line or a propane tank.

Most homeowners choose their go-to fuel source depending on their intended budget and preference. Here are some of the most popular fuel types for generators:

  • Gasoline - Generators running on gasoline prove to be a more cost-effective option than diesel or natural gas ones. However, its running maintenance expenses will be more expensive as gasoline costs more than non-renewable fuels. It is also a highly flammable material, making it challenging to store safely.
  • Natural Gas - Although natural gas generators are cheap to install, the operational costs can be more expensive than diesel-powered units. These machines take their fuel from the local utility grid source, so you won’t have to add fuel to it frequently. But, natural gas may be unavailable in some areas– so you will need to have it connected for a consistent supply.
  • Diesel - Considerably the most expensive generators to install, diesel generators are built using intricate components. As a result, this will also increase the associated expenses. The good news is, its operating and maintenance costs are cheaper than units powered by other non-renewable fuel types.
  • Liquid Propane - A liquid propane-powered generator runs on gas. For homeowners without a propane supply at home, you will pay around $55 to $130 per hour to build a propane tank at home. Generally, you will need frequent deliveries to ensure you won’t run out of fuel.
  • Solar - If you want to own an entirely environmentally friendly home, a solar-powered generator makes for a great choice. It might cost you more upon installation– but you will end up saving more on energy bills in the long run.


The larger your preferred generator is, the more circuits you’ll need to have it wired on. Small-sized generators can work with only several circuits, so installing a large generator will cost you more as it will need more work. Keep in mind that the size of generators is measured in kilowatts (kW). It will be the measurement of how powerful your unit will be.

If your chosen generator unit has a higher kW, you can expect more standby power in the event of a random blackout. Generators for home use begin at 5 to more than 50 kW in size. However, these machines typically come at a cost. Consult an electrician to determine your home’s ideal generator size. They will calculate the electric load of all the appliances you want to run amid a power outage– ensuring that your generator unit will have sufficient power.

Some relevant data that your electrician will calculate are as follows:

  • The appliance’s running wattage, which refers to the total consumed power on regular operation days
  • The appliance unit’s starting kVA (kilovolt-amperes) determining the amount of electricity it draws on start-up. It is essential data to ensure your unit can handle any extra electrical surge.

Once the data listed above have been measured precisely by your electrician, you can now make an informed decision regarding the right size of your whole-house generator.

Location of Generator

Several homeowners remain uncertain about the proper placement of their generators. A great rule of thumb to follow would be placing your unit near the electric meter. However, if you want to go with a natural gas generator route, have it somewhere between the electric meter and the gas meter. The decision will also greatly depend on your home’s layout and any local safety requirements in your area.

Technically, the installation will cost you more if your generator is located far away from the electric or gas meter lines. It would require more labor on your contractors, as they will have to run necessary wires from your unit to the meters. Also, some whole house generators will require some foundation (concrete or gravel) for support. The construction of this will only add to your installation expenses, ranging from $70 to $90 per square foot for preparing the site and pouring the concrete.

The best way to determine the perfect placement of your whole house generator is to consult your contractor for assistance. Aside from informing you of the right location, they’ll also ensure your unit complies with local codes.

Transfer Switch

Suppose some existing electrical equipment needs to be updated to ensure your generator’s efficient operation, such as adding a subpanel near the automatic transfer switch. This scenario will only increase the costs of installing a whole house generator.

Working transfer switches are essential to have in your home, as these detect live power outages to move the power load to your generator. In portable generators, these units do not need transfer switches since they are wired into the electrical panel. Some homeowners opt to have them installed, however, to save themselves from working with extension cords. 

A regular standby generator, in contrast, needs proper transfer switches to function efficiently. Your electrician can install a transfer switch at home for about four hours, which may cost you around $1,500 in installation costs.

Other Electrical Modifications

Since a whole house generator installation varies on a case-to-case basis, consider the electrical modifications for your home to be unique. You can count on your electrician to be in charge of determining the necessary upgrades needed for your existing electrical system. Here are some common examples of electrical modifications in installing a whole house generator:

  • Upgrading the electrical panels
  • Replacing faulty, old wirings with new ones to ensure compliance with local codes or new generator compatibility
  • Upgrading the existing transfer switch for a seamless power switch in a blackout

The labor on the electrical panels and new wirings will typically cost you around $80 to $100 per hour. It is necessary to assess and inspect your current electrical system to determine the required electrical modifications. In turn, the more upgrades or electrical work you’ll need, the more your total installation expenses will be. Best prepare your budget for this aspect to ensure your generator will function smoothly.


With several house generator brands on the market; how do you choose the right one for your needs? Well, we believe there is a perfect unit for everyone. As long as you take your budget, preference, and purpose into account– you’ll find the generator of your dreams.

If that still proves to overwhelm your decision-making process, you can never go wrong with a trusted generator brand that has been in the market for long years. Although you will end up paying a bit more, you can expect these units to be durable and long-lasting. You may consider some crowd-favorite brands: Champion Power, DuroMax (a dual fuel hybrid generator with electric start), Durostar, and Westinghouse (a dual fuel generator).

Trust us; the investment will pay off, in the long run, to save more money on repairs and the like. These brands usually come with a warranty to ensure you’ll enjoy an efficient generator unit for a long time.

Running Costs

Of course, you cannot take running costs out of the equation for a whole house generator. If you want to maintain your generator’s tip-top shape, you will need to run it at least once a week. A 15-minute generator operation will cost you $8 on average, which amounts to $416 in a year just on generator maintenance. It does not account for the costs incurred in an actual and extended power outage.

It’s also crucial to have a technician assess the condition of your generator unit at least once or twice a year. Depending on your technician’s hourly rate, you can expect to pay $70 to $90 for their professional services. Should you need minor repairs, prepare to shell out $80 to $320 as well.

Key Considerations before Buying a Whole House Generator

You can expect to be charged for your whole house generator installation at a per-project cost. Depending on your contractor, however, there might be several other individual factors to take into consideration, such as:

  • Plumbing connections: In using liquid propane or natural gas as a fuel source for your generator, you’ll need to ensure the unit is properly connected to the gas line or propane tanks.  Accordingly, you will need to use the correct valve.
  • Permits: When installing a whole house generator, it’s best to keep in mind that you will need to secure local permits. It may cost you around $55 to $230 on average. However, homeowners cannot apply for this permit. You will need to keep in touch with your electrician or contractor so they will handle the permit processing. It is always crucial to obtain the pass before the project begins.
  • HOA restrictions: Besides local permits, you will also need to check particular homeowners’ association (HOA) restrictions or building permits before the installation. Initial on-site inspections may also be required, which vary depending on your specific neighborhood.
  • Other Material and Equipment: Naturally, you will need unique material and equipment for a successful whole house generator installation. Note that the essential tools in your toolkit won’t suffice. There is no need to worry, though; your contractor can provide all the relevant machinery you need for the project. You will also need protective gear to avoid gas leaks, potential electrocution, or carbon monoxide poisoning. Expect to shell out somewhere around $350 to 2,500 to cover this aspect.

Project Process of Installing a Whole House Generator

So, what goes down in a whole house generator installation? For your reference, let’s take a closer look at the project process involved:

Step by step process one whole house generator installation
  1. 1
    On-Site Visit and Assessment: Before getting started with all the labor, your contractor might require an on-site visit to select the ideal location for your generator. Usually, this is in the area or space near the gas meter– to limit adding new wires or pipes. Local codes and other relevant guidelines will also be taken into consideration by your electrician.
  2. 2
    Securing Permits: As previously mentioned, you will need to secure the necessary permits for your whole house generator installation project. Hiring a professional contractor will take the load off from homeowners, as they will be the ones to work on getting the building, electrical, or plumbing permits. Furthermore, there may also be some more paperwork or fees associated with your neighborhood HOA.
  3. 3
    Actual Installation: After the site preparation, your contractor will set the generator on an elevated area (either a concrete pad or wooden platform) to ensure your unit will be flood-proof. Once in place, the gas line and a new transfer switch need to be connected. The latter will serve as a trigger for your generator to provide backup power seamlessly in the event of a power outage.
  4. 4
    Inspection: In some areas, you may need to pass one final city inspection before you can start enjoying the benefits and convenience of your whole house generator. It’s best to do a quick online search if your state requires one or ask your contractor if you need one for your home.
  5. 5
    Meter Change-out: For generators powered by natural gas, your local utility company will stop by your home to upgrade your gas meter upon securing all necessary permits and passing all inspections. Keep in mind that this step depends on your preferred generator type.

Benefits of Whole House Generator

Undoubtedly, having a whole house generator at home will bring convenience to your life like no other. You will no longer need to worry about running out of power in the event of an outage– a generator proves to be a reliable energy solution to power your appliances and electronics. (Related: How Much Value A Whole House Generator Adds To Your Home (And Out Best Picks))

In particular, installing a whole house generator (aka standby generators) is an ideal choice for your household in terms of efficiency. These large-sized units may cost you more than portable ones, but you can count on their power for extended periods of blackout. (Even if the power goes out, you may continue using your freezer, HVAC unit, alarm system, and water heater.

Let’s discuss the significant benefits of a whole house generator in detail.

  • Fuel Efficiency: Given that whole-house generators are directly hooked to the gas line in your home, it ensures smooth operation whenever electricity is unavailable. There is no need to worry about securing several fuel tanks at a given time to ensure your generator will keep on running. In contrast, portable units need a gasoline or propane tank before you can even switch it on. You will need to ensure you have a sufficient supply of tanks during power outages. It can be pretty challenging during extended outages, however. If you’re wondering about its power duration, safe to say, it will last for as long as necessary. It’s all thanks to the machine’s direct connection to a gas line. Your entire household can still use electricity as if there’s no ongoing power interruption. How convenient, right?
  • Convenience: The added convenience of a whole house generator is one of its primary selling points. Imagine having uninterrupted power during an extended period of a power outage– what a game-changing home solution! Turn on the switch as soon as the electricity goes out, and your backup power will be instantly up and running. There’s no need to deal with uncomfortable days or nights as you may still enjoy the convenience of major appliances.AC units, heaters, freezers, name it, and a whole house generator may power it over an extended period. Not to mention, it also ensures that your essential electronics (such as mobile phones and laptops) won’t run out of battery. The scope of a standby generator may be too broad for some homeowners, given that it is designed to provide power for the entire house. Let your electrician know about your preference if you want to have it powering only a few home appliances. Of course, it is your responsibility still to have your generator unit assessed and inspected by a professional at least once a year. Maintaining your unit in good shape is crucial if you want consistent electricity, even in the middle of severe storms.
  • Safety and Security: There’s nothing like getting a good night’s sleep knowing that your home alarm system is functioning as usual, despite an ongoing power interruption. If you want to improve your home’s security– getting a whole house generator is the way to go. Additionally, these generators do not release any harmful fumes. It will keep your home safe from any potential carbon monoxide build-up, which is better for your health as well as the general household environment. With sufficient lighting even during a power failure, you can save yourself from tripping over furniture in the dark, falling down the staircase, and other accidents. Although standby generators will cost you a hefty sum on the installation and upkeep costs, they will give you peace of mind every time power goes out.
  • Long-term ROI: Who doesn’t want to save money in the long run, right? We’re here to tell you installing a whole house generator will help you get a long-term return on investment. You’ve read that part right. The upfront costs in buying a standby generator may be expensive, but you will be saving up on repairs and necessary parts replacement further down the road. For instance, your generator unit will protect your pipes from freezing on cold winter nights. Your refrigerator will also continue to function without interruption, saving you from dealing with spoiled or rotten food. Let’s say you live in an area with frequent electricity outages. Over 6 to 10 years, all the savings will add up to a positive ROI. If you’re still undecided on having one installed at home, think of the saved-up costs you are currently missing out on– and continue to do so without a whole house generator. There’s also no need for a hotel stay, even if you’re unable to shower with hot water at home. Having a generator will help you enjoy a consistent supply of warm water. You will no longer need to spend on hotel expenses, as your home will be as convenient as before.

Checklist in Choosing a Contractor

If you’ve decided on going with a contractor for their services, you will undoubtedly benefit from high-quality contractors to do flawless work. You can rely on your whole house generator to work efficiently and smoothly. Although it is tempting to sign with contractors offering much cheaper labor, you may be at risk of dealing with subpar work and haphazardly done generator installations.

Since a whole house generator is already a hefty investment on its own, the last thing you’d want is to realize it doesn’t work as smoothly as intended. Hence, prepare your budget accordingly to avail the service of a top-quality contractor. They will ensure that your generator unit efficiently works when you need it the most amid a power outage.

If you want to ensure your contractor’s expertise, here are some guide questions to keep in mind:

  • Are they licensed and insured?
  • Will they cover the relevant permits in the generator installation?
  • Do they offer direct or upfront pricing before the project begins?
  • Are they offering any warranties for their work?
  • Do they have several positive testimonials from previous customers?
  • Are there more negative feedbacks than positive ones?

Note that these questions will serve as guidelines to help you choose a high-quality team of contractors. Having more positive reviews than negative ones already gives you an idea of how well they do the job. Regardless, hiring professional contractors ensures a safe installation, given their extensive background and experience. They can also assist you in selecting the best generator units to fit your needs.

If you’re overwhelmed to choose from choices, you can always ask your friends and neighbors for personal recommendations. Picking a high-quality brand as well as a contractor team will heavily rely on good reviews. Also, you will want to sign with a local contractor known for their excellent customer service. Don’t limit yourself to only one or two choices. Commit some time to shop around to ensure you’ll make the most bang out of your buck.

Whole House Generator: Frequently Asked Questions (FAQs)

What is the difference between a whole house generator versus a partial house generator?

The significant difference between a whole house generator and a partial house generator is the power it can provide. As the name implies, a whole house generator can supply a complete fail-over for your entire home’s electricity. Meanwhile, a partial house generator can only provide power in selected circuits such as outlets, lights, and appliances.

How long do generators last?

A typical standby generator has 20 to 40 years of good use, depending on how well it is maintained, its running time, and how often it is operated.

How to determine the ideal generator size for my house?

Purchasing a generator is a significant investment for your home, businesses, and workplace, which is why picking the right size is one of the most important things every homeowner must know. Here are the steps to help you size up the ideal generator for you:

  • The first thing you must do is keep track of all the items that will be powered and form a list from it.
  • Find out the energy needed to turn it on (starting energy) and the energy required to operate (running wattage). Most equipment usually has these figures attached to them in some way.
  • Using a power calculator, calculate the energy required by summing up kW/KVA figures.

Upon knowing the necessary power needed for your home, you can now decide on the best generator size suited for it.

Which fuel type is the best?

Keep in mind that each generator fuel type has its own set of pros and cons. Gasoline, for instance, can be accessible but highly flammable. It can be risky to store bulk amounts of gasoline at home. In contrast, liquid propane comes with a longer shelf life. Perhaps the only downside is its large, spacious tanks. Meanwhile, diesel is the less risky choice as it is the least flammable. However, it will be technically unusable when left idle for two years.

How much maintenance does a whole house generator need?

It is crucial to have your whole house generator regularly serviced and maintained by professionals. Doing so will ensure your unit will run on its utmost functionality, with long service life. It’s ideal to have it assessed once every six months by an authorized generator service dealer, although you may also go as far as once per year.

What is the most common generator maintenance problem?

Technicians note that fuel-related issues are the most common generator maintenance problem. It is commonly brought by clogged fuel injectors, dead batteries, and a potential algae buildup in the unit.

Final Thoughts

At this point, there’s no need to wait until the next power interruption to push your whole house generator installation plans finally. Keep in mind that it is an excellent long-term investment for many homeowners, and it won’t hurt to join the growing list.

Not only does it offer convenience and comfort during extended periods of having no electricity, but it also guarantees safety and security on your end. Consult a local generator specialist today to make your home blackout-proof.

Trust us; this investment will undoubtedly pay off in the long run.

Kenneth Wilson
September 25, 2021
Cost Guides, Interior

Kenneth Wilson

Retired contractor. Currently residing in Southwest Florida. Now in semi-retirement, I write and manage this blog focused on helping home owners make savvy decisions when it comes to finding contractors and getting their projects done. I also operate remodeling design service for homeowners.

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