Service Panel Upgrade Estimate: What to Expect in Milwaukee and Waukesha County

A service panel upgrade replaces your home’s main electrical panel with one that handles more capacity, meets current safety standards and supports modern appliances. A straightforward swap usually takes about a day of on-site work, and the price depends mainly on the amperage increase and whether the service entrance and meter socket also need replacing. An accurate estimate requires a licensed electrician to assess your panel, service entrance and household load.

If the panel is warm to the touch, smells hot, buzzes or shows scorch marks, leave it alone and call an electrician today rather than waiting for an upgrade to be scheduled.

---

What a Service Panel Upgrade Actually Involves

A service panel, sometimes called a breaker box or load center, is the metal cabinet where your utility’s power enters the home and splits into individual circuits. Upgrading it means removing the old panel, installing a new one rated for higher amperage (the amount of electrical current it can carry), reconnecting every circuit to new breakers and often replacing the service entrance: the wiring that runs from the utility connection down into the panel.

A licensed electrician also checks the grounding system, the main bonding jumper and the condition of the existing wiring before reconnecting anything. On older homes, the work can uncover deteriorated insulation or undersized wiring.

Some circuits may also need protection the old panel never had. AFCI breakers (arc fault circuit interrupters) detect dangerous arcing in wiring before it can start a fire.

GFCI protection (ground fault circuit interrupters) shuts off power when as little as 4 to 6 milliamps leaks out of a circuit by any path, including through water or a person.

None of this is a homeowner project. Federal Pacific Stab-Lok and Zinsco panels are flagged by many home inspectors and insurers over concerns that their breakers may not trip reliably, and many electricians recommend replacing them, although the Federal Pacific concerns never led to a federal recall. The permit process exists to verify the work was done correctly.

---

How to Tell If You Need an Upgrade

A breaker trip is a symptom, not a diagnosis, and it can point to a problem on one circuit rather than a panel that is too small. If a breaker trips, reset it once: push it firmly to OFF, then back to ON. If it trips again, leave it off until an electrician checks the circuit.

If you notice a burning or hot-plastic smell, scorch marks, discoloration or buzzing at the panel, leave the breaker off, stop using that circuit and call an electrician. Do not touch the panel to check it for heat.

Whether you need an upgrade is decided by a load calculation, the electrical code’s method for adding up your home’s demand and comparing it with the panel’s rated capacity.

Situations that commonly lead to an upgrade estimate:

• A 60- or 100-amp panel in a home that now runs central air conditioning, an EV charger, a heat pump or an electric range
• Breakers tripping across several circuits under normal use, once an electrician has ruled out faults on each circuit
• A fuse box still in service instead of a modern breaker panel
• A Federal Pacific Stab-Lok or Zinsco panel, brands with long-standing concerns about breakers that may not trip reliably
• A home addition or kitchen remodel that adds substantial new load
• An insurance company requesting an upgrade as a condition of coverage

Older Milwaukee and Wauwatosa bungalows from the 1920s to 1950s were often built with 60-amp services, and some still have knob-and-tube wiring, so capacity is a common question in these homes. An upgrade is not always the answer, though. Sometimes a load calculation shows the existing panel has capacity to spare, and a new circuit or a subpanel solves the problem. You will not know until an electrician runs the numbers.

---

What Decides the Cost of a Panel Upgrade

This guide does not list prices, because the factors below move the total too much from one house to the next for an average to be useful. Knowing them helps you compare quotes fairly.

Factor	Lower-cost scenario	Higher-cost scenario
Amperage upgrade	100A to 200A	100A to 400A-class service (large home)
Service entrance conductors	Existing conductors are adequate	Must be replaced to the meter
Meter socket	Utility-compatible, good condition	Needs replacement
Grounding system	Modern ground rods in place	Needs new ground rods and bonding
Panel location	Accessible, dry basement	Finished wall, crawl space or attic
Required code upgrades	New panel only	AFCI/GFCI breakers on multiple circuits
Permit and inspection	Standard residential	More involved local requirements
Utility coordination	Utility reconnects the same day	Scheduling delay adds a return trip

The amperage jump matters most, and the common upgrade path is 100 amps to 200 amps. Larger homes, detached garages or properties with heavy shop equipment may need a 400-amp class service, which is typically built on a 400-amp class meter socket (rated 320 amps continuous) and often feeds two 200-amp panels, so it takes different equipment and more material.

For a rough ballpark, try Lehmann’s online panel upgrade calculator, which walks through these factors for this area.

---

How Long It Takes and What Gets Disrupted

An electrician can usually complete a straightforward 100-amp to 200-amp panel swap in about a full workday when the service entrance conductors are in good condition and the utility can reconnect the same day. Before the old panel comes out, the utility (We Energies in most of the Milwaukee area) has to disconnect power, usually by pulling the meter.

Add time for any of these:

• Service entrance replacement often adds several hours.
• Inspection scheduling can mean a separate visit, because in some municipalities the inspector must sign off before the utility restores permanent power.
• Aluminum branch-circuit wiring in some older homes needs separate remediation, which an electrician will flag rather than fold into the panel swap.

You will be without power for most of the workday. If anyone in the home relies on powered medical equipment, tell the electrician before scheduling.

Permit processing and utility scheduling add lead time before and after the work, and both vary by municipality. Your electrician can give you a project-specific timeline after the site visit, and our guide to panel upgrade costs and timelines walks through each stage.

---

Permits and Inspection

Under Wisconsin’s electrical code, SPS 316, a service panel upgrade needs an electrical permit, issued by your municipality. In the City of Milwaukee, permits come from the Department of Neighborhood Services, while Wauwatosa, Waukesha and other municipalities issue them through their own building inspection offices. The permit puts an inspector on site to verify the work, and in some municipalities the utility will not restore permanent power until the work passes.

SPS 316 adopts the 2023 National Electrical Code with state amendments (in effect since September 1, 2026). When you hire an electrician, they apply for the permit, and the fee is either included in the quote or itemized separately.

Our guide to permits for panel upgrades covers the process in more detail.

Skipping the permit creates real problems. Unpermitted work can complicate an insurance claim after a fire, and it can surface during a home sale when the buyer’s inspector reviews the panel. A reputable electrician will not propose skipping the permit.

---

Choosing an Electrician for a Panel Upgrade

Panel upgrade work is not handyman territory. Switching the main breaker off does not de-energize the service conductors or the main breaker’s line-side lugs; only the utility, usually by pulling the meter, or a separate service disconnect ahead of the panel can. Mistakes here cause electrical fires and electrocution.

When comparing electricians, ask these questions directly:

Is the work led by a Wisconsin master electrician? A Wisconsin master electrician license requires passing an exam and documented field experience. The business should also hold its own Wisconsin electrical contractor credential. Lehmann Electrical & Design is led by licensed master electrician Jacob Lehmann.

Will you pull the permit and coordinate with the utility? The answer should be yes. If an electrician suggests you pull the permit yourself or skip it, treat that as a red flag.

What does the quote include? A complete quote itemizes the panel, breakers, grounding, permit fees and utility coordination, plus service entrance conductors and meter socket work if they are needed.

What happens if the inspector requires additional work? Get the answer in writing before you sign.

Before you book, you can see what Lehmann’s panel upgrade service includes.

---

---

Frequently Asked Questions