How much does it cost to install a generator transfer switch?
Ashburn, VA

How much does it cost to install a generator transfer switch?

Ashburn, VA

How much does it cost to install a generator transfer switch?

$600 – $2,500automatic transfer switch cost installed
$400 – $1,300manual transfer switch cost installed
$400 – $850interlock kit cost installed (switch alternative)

Get free estimates for your project or view our cost guide below:

$600 – $2,500 automatic transfer switch cost installed

$400 – $1,300 manual transfer switch cost installed

$400 – $850 interlock kit cost installed (switch alternative)

Get free estimates for your project or view our cost guide below:
Tara Farmer
Written by
Tara Farmer
Edited by
Kristen Cramer
Fact-checked by
Tom Grupa

Cost to install a transfer switch for generator

The cost to install a generator transfer switch is $400 to $2,500 on average for the unit and labor. An automatic transfer switch costs $400 to $2,000 for the unit alone, while a manual transfer switch costs $200 to $800. A generator interlock kit costs $400 to $850 installed.

Generator transfer switch cost - chart
Generator transfer switch cost - chart
Cost to install a generator transfer switch
Switch type Switch unit price Total cost to install
Manual transfer switch $200 – $800 $400 – $1,300
Automatic transfer switch $400 – $2,000 $600 – $2,500

  • Manual transfer switches are ideal for portable generators, but the switch must be flipped manually when the power goes out.

  • Automatic transfer switches are optimal for standby generators and automatically turn on a generator during a power outage.

Generator transfer switch installation cost breakdown

Transfer switch installation cost breakdown
Factor Average cost
Transfer switch $200 – $2,000
Installation labor $200 – $500
Power inlet box* $20 – $100
Heavy duty power cord* $30 – $350

*Not needed for every installation scenario.

Factors affecting the cost include:

  • Amp requirements – Higher amp transfer switches typically cost more than lower amp models. The transfer switch's amperage should match the main panel or the generator's amperage.

  • Manual vs. automatic – A manual transfer switch costs less and takes less time to install than an automatic transfer switch, reducing both labor and material costs.

  • Number of circuits – A 6-circuit transfer switch is cheaper than a 10-circuit transfer switch but provides fewer connections to the main breaker panel.

  • Kit vs. individual parts – Transfer switch kits cost $300 to $500 on average and are available for many smaller amperage models. Purchasing a kit that includes the switch panel, power inlet box, and power cord may reduce the total material cost.

  • Electrician experience – Master electricians charge more than Apprentice or Journeyman electricians due to their higher education and experience level.

  • Existing electrical – The home may require electrical modifications before installing a transfer switch if its current system is not up to code.

  • Permits – Electrical permits costs $50 to $350. Most areas require a permit and inspection when making any changes to the home's electrical system.

Electrician labor cost to install a transfer switch

The labor cost to install a transfer switch is $200 to $500 for a straightforward installation with no complications. Electricians charge $50 to $130 per hour, plus a $75 call-out fee. Installation takes 2 to 4+ hours, depending on the switch type and the home's layout and electrical system.

Many cities require a licensed electrician to install a transfer switch due to backfeeding, fire, and electrocution risks associated with incorrect installations.

Generator hooked up to transfer switch
Generator hooked up to transfer switch

Cost to wire generator to house

The cost to wire a generator to a house is $3,000 to $5,000 for labor alone when installing a whole-house generator. The home's layout, fuel source, and the amount of wiring and gas plumbing needed impact the cost. A whole-home generator creates enough power to support all the home's circuits.

  • A whole-home generator costs $3,000 to $6,000 for the unit alone, depending on the size.

  • A portable generator costs $500 to $2,500 on average.

  • An automatic transfer switch immediately shifts the power source from the utility line to the standby generator upon detecting an outage.

Cost to install interlock kit for generator

Installing an interlock kit costs $400 to $850 for labor and materials and provides a transfer switch alternative. The generator is wired directly to the home's main electrical panel, and a sliding metal plate allows only the generator or main breaker to be on at one time, preventing dangerous backfeeding.

Cost to install an interlock kit for a generator
Factor Average cost
Interlock kit $50 – $150
Job supplies* $200 – $400
Labor $150 – $300
Total cost installed $400 – $850

*breaker, inlet box, cord, misc.

Transfer switch cost by type & size

A transfer switch costs $200 to $8,000 for the switch alone, depending on the size and type. Size the transfer switch's amperage to match the main breaker panel's amperage or the generator's amperage to use the generator's maximum power capabilities.

Transfer switch cost by type & size
Amperage Maximum generator watts Unit price range*
30-amp 7,500 – 8,000 $200 – $500
50-amp 8,500 – 12,500 $260 – $900
100-amp 10,000 – 24,000 $300 – $950
200-amp 45,000 – 48,000 $680 – $1,500
400-amp 25,000 – 96,000 $1,800 – $3,200
600-amp 96,000 – 144,000 $5,000 – $7,800
800-amp 192,000 –288,000 $5,500 – $8,000

*Not including installation.

  • Most smaller portable generators are 30 or 50 amps.

  • Large standby generators are typically 100 to 200+ amps.

  • Installation adds $200 to $500 to the total cost.

Cost of manual transfer switch

The average cost to install a manual transfer switch is $400 to $1,300 for labor and materials. Manual transfer switches require manually flipping the switch from utility to generator power when experiencing power loss—best for areas with infrequent outages or for smaller homes with portable generators.

  • A manual transfer switch costs $200 to $800 on average for the part alone, depending on the amperage and number of circuits.

  • Manual transfer switches are simpler and take less time to install than automatic transfer switches.

Cost of automatic transfer switch for generator

An automatic transfer switch costs $600 to $2,500 installed or $400 to $2,000+ for the switch alone, depending on the size. Automatic switches are ideal for standby generators in areas with frequent power loss. These devices shift the home's power source to the generator automatically upon detecting an outage.

6-circuit vs. 10-circuit transfer switch prices

Multiple circuit transfer switch prices are $200 to $1,200 on average. The generator's power output dictates the number of circuits possible. 6-circuit transfer switches work well in most homes to power critical functions, such as a water heater, water pump, refrigerator, heating or cooling, and some lighting.

Transfer switch prices by circuits
Number of circuits Generator size needed (watts)* Unit price range Best for:
6 5,000 – 7,500 $230 – $360 Essential circuits or smaller homes
10 7,500 – 12,500 $300 – $670 Most or all circuits in an average size home
12+ 12,000+ $500 – $1,200+ Most or all circuits in larger homes and buildings

*Consult the manufacturer guidelines as wattage requirements vary by brand and model.

Transfer switch FAQs

What is a transfer switch?

A transfer switch is a panel connecting a generator to a home's hardwired circuits, allowing the generator to directly power either the home's essential appliances or the whole home during an outage. Some transfer switches must be flipped manually, while others detect outages and switch automatically.

The transfer switch also prevents the generator from backfeeding power into the utility line during an outage. This safety measure protects utility workers from being electrocuted while repairing the lines.

How long does it take to install a transfer switch?

Installing a transfer switch takes 2 to 4 hours on average for professional installation. An electrician installs an exterior power inlet box for the generator, an interior transfer switch panel, and wires the desired circuits from the home's main panel to the transfer switch panel.

Does a transfer switch work with portable generators?

A transfer switch works with portable generators 5,000 watts and above. Connecting a portable generator to a house without a transfer switch or interlocking device is not recommended and is illegal in many places due to fire and electrocution risk from backfeeding into the main power supply.

How far can a generator be from the transfer switch?

Most generators can be 60 to 70 feet from the transfer switch, enough distance to reduce noise in the home and still maintain efficiency. Placing a generator farther away weakens the system, increases connection failure risk, and reduces the homeowner's ability to hear if the generator has an issue.

Can I install a generator transfer switch myself?

You can install a generator transfer switch yourself in some cases, but experts do not recommend it. Both manual and automatic transfer switch installations involve working with live, potentially hazardous electrical terminals. Hire a licensed electrician to ensure the job is done safely and correctly.

Getting estimates from transfer switch installers

Before hiring an electrical contractor to install a transfer switch, be sure to:

  • Know the transfer switch type you are installing, your generator type and size, and your home's current electrical system details to help the electrician provide an accurate estimate.

  • Get three in-person estimates to compare.

  • Check their reviews on HomeGuide and Google.

  • Hire a company that is licensed, bonded, insured, and has been in business for 5+ years.

  • Avoid hiring the company with the lowest quote as quality may suffer.

  • Get a detailed contract and warranty in writing before the work begins.

  • Never pay in full before the project is complete. Work out a payment plan instead.

Questions to ask

  • How long have you been in business?

  • Are you licensed, bonded, and insured?

  • What experience do you have installing transfer switches?

  • What transfer switches are compatible with my panel and generator?

  • Can you provide local references with contact information?

  • Do you handle the permits and inspection process?

  • Is there any prep work I should do ahead of time?

  • Are all permit fees included in the estimate?

  • What additional costs might come up during installation?

  • How long will the installation take?

  • How long does a transfer switch last?

  • Do you offer a warranty. If so, what does it cover?

  • How do you handle payments?