Home › Guides › Generator interlock in Michigan · Checked Nov 15, 2026
Generator interlock in Michigan: cost, permit, how it works
The short answer
An interlock is a sliding metal plate on your breaker panel. It makes it impossible to have the main breaker and the generator breaker on at the same time, so generator power can’t flow back onto the street.
- GeneratorOutside, 20+ feet away
- Inlet boxOn an outside wall
- Generator breakerWired from the inlet
- Interlock plateMain off before generator on
Cost range: HomeGuide. Permit rule: Michigan LARA.
Interlock vs. the other two ways
| Interlock | DTE meter plug | Transfer switch | |
|---|---|---|---|
| Upfront | $400–$850 | $99.99 or $249.99 | Typically $1,500 (DTE’s estimate) |
| Monthly | $0 | $22.99 | $0 |
| Circuits | Any in the panel | Any in the panel | Usually 6 to 8 wired |
| Who installs | Licensed electrician, permit | DTE, at the meter | Licensed electrician, permit |
| Works with | Any utility | DTE only, 200 A or less | Any utility |
Sources: HomeGuide, DTE plan page, DTE FAQ. Get quotes for your house.
More detail
Michigan permits, in plain terms
Michigan requires an electrical permit for this work. A licensed electrical contractor pulls it, or you can as a homeowner doing the work yourself in a single-family home you own and live in. Either way, it gets inspected. Many cities and townships run their own permit office. (Michigan LARA)
A good fit if
- You’re with Consumers Energy or another utility with no meter plug
- You’ll stay a while and don’t want a monthly fee
- An interlock kit is made for your exact panel
- There’s room in the panel for a generator breaker
Look elsewhere if
- No kit fits your panel (ask about a transfer switch)
- You’re with DTE and want it done fast with no contractor: see the meter plug
- You want power to switch over by itself: that’s a standby
Your plan
- Photograph your panel label. Brand, model and amps.
- Get 2 or 3 quotes from licensed electricians. Check the license with LARA.
- Ask three questions. Is the kit made for my panel? 30-amp or 50-amp inlet? Is the permit included?
- Install and inspection. Keep the permit paperwork with the house records.
- Practice once on a nice day. Main off, slide the plate, generator breaker on, then circuits one at a time.
Questions people ask
Are generator interlock kits legal in Michigan?
Michigan requires an electrical permit and inspection for the wiring. Use a kit made for your exact panel; your local inspector decides whether the installation passes.
How much does a generator interlock cost?
HomeGuide puts a generator interlock at $400 to $850 installed. Your panel, the distance to the inlet box and the permit fee move the number.
Interlock kit or transfer switch?
An interlock lets you run any circuit in the panel. A basic transfer switch has 6 to 8 wired circuits, and DTE estimates one typically costs $1,500 installed.
Can I install an interlock myself in Michigan?
Michigan lets a homeowner pull a permit for work they do in a single-family home they own and live in, and it is inspected like a contractor’s work. We suggest a licensed electrician.
Keep reading
Two rules that save lives
Never run a generator in a garage, porch or near a window. Keep it 20 feet out, exhaust away.
Never backfeed through a dryer outlet. A ‘double-male’ cord can electrocute a lineman down the street. Your plan uses only safe, legal ways to connect.
Not sure which fits your house? A few taps about your home and what has to stay on. Free, and no email needed to see your plan.
Take the quiz: under 2 minutes- DTE: Surge Protection Plus plan details: www.dteenergy.com
- DTE: Surge Protection support center (FAQ): www.dteenergy.com
- HomeGuide: Whole house generator cost (2026): homeguide.com
- Michigan LARA: Electrical permit information: www.michigan.gov
- Michigan LARA: Verify a License: aca3.accela.com
Lights Back On is not affiliated with DTE Energy. Educational content only; not electrical advice.