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Cost Guide

Generator Transfer Switch Cost

Next Phase Electric is a licensed and insured electrical contractor in Covington, WA, installing generator interlock kits, inlet boxes and transfer switches across South King and Pierce County.

Three things set most of the price: the panel, the inlet size and how far the inlet is from the panel.

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Licensed, Bonded & Insured♦15+ Years Experience♦2,500+ Homes Served♦5.0★ on Google♦Background-Checked Technicians ♦ Code-Compliant Work ♦ Upfront Pricing ♦ Same-Day Service Available ♦ Permit Pulling & Inspections ♦ Covington & Nearby Cities ♦ Licensed, Bonded & Insured♦15+ Years Experience♦2,500+ Homes Served♦5.0★ on Google♦Background-Checked Technicians ♦ Code-Compliant Work ♦ Upfront Pricing ♦ Same-Day Service Available ♦ Permit Pulling & Inspections ♦ Covington & Nearby Cities ♦

What Drives the Cost

What Sets the Price

These six things decide the size of the job.

Type of Hookup

An interlock kit with an inlet box costs the least. A manual transfer switch costs more. An automatic switch for a standby generator costs the most.

Your Panel

An interlock has to be made for your panel model. A panel with no interlock made for it gets a manual transfer switch.

Inlet Size

A 30-amp inlet suits generators up to about 7,500 watts. Larger generators need a 50-amp inlet and heavier wire.

Distance to the Inlet

The inlet goes on an outside wall. The farther it is from the panel, the longer the run.

Number of Circuits

A manual transfer switch is wired to six to ten chosen circuits. More circuits means a larger switch.

Panel Condition

Federal Pacific and Zinsco panels have no interlock made for them, and they should be replaced first.

Included

What the Price Covers

One flat price for the whole job.

The interlock kit or transfer switch

The inlet box on the outside wall

Electrical permit and inspection

A test run on your generator with the main locked out

Labeled breakers

You get the exact price first and approve it before any work starts.

Get My Price (253) 796-8658

5.0 on Google

2,500+ Homes Served

How It Works

How You Get Your Price

The exact price comes upfront. You approve it before any work starts.

You Book

Online or by phone. A technician reaches out within 1 business hour.

We Match the Kit

Tell us the wattage and plug type of the generator and send a photo of the panel. We confirm the kit and give you the exact price.

Installed and Tested

Most installs take half a day. We run the house on your generator before we finish.

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FAQ

Common Questions

It depends on the panel, the inlet size and how far the inlet is from the panel. You get the exact price after we see the panel, before any work starts.

An interlock kit with an inlet box. It uses the panel you already have, lets you run any circuit, and makes backfeeding the utility impossible. A manual transfer switch costs more and limits you to the circuits wired into it.

Yes. An interlock uses the panel you already have. A manual transfer switch is a second box beside the panel, wired to six to ten chosen circuits.

A little. It uses heavier wire and a larger breaker. Match the inlet to the biggest 240-volt outlet on the generator.

No. An interlock has to be made for that panel model. Most Square D, Eaton, Siemens and GE panels have one. Federal Pacific and Zinsco panels do not, and those should be replaced anyway. We check yours from a photo.

Yes. It is new wiring at the panel and it gets inspected. The electrical permit is included, and we meet the inspector.