Federal Pacific & Zinsco Panels: What to Know

Published October 20, 2026 · Panels

Short answer: the U.S. Consumer Product Safety Commission (CPSC) investigated Federal Pacific Electric (FPE) Stab-Lok circuit breakers and closed the case in 1983 without a safety determination. CPSC said the available data "does not establish that the circuit breakers present a serious risk of injury to consumers," and that it closed the investigation "without making a determination as to the safety of FPE circuit breakers" (CPSC, 1983, revised 2011). For Zinsco, we found no CPSC statement at all. If your home has either brand, or any older panel, ask a licensed electrician to evaluate it.

Both brands come up a lot in home inspections and online forums, and the claims you'll read vary widely. This post sticks to the public record and explains how Fort Collins-area homeowners can get a straight answer about their own panel.

What CPSC said about Federal Pacific Stab-Lok breakers

CPSC's news release, dated March 3, 1983 and revised February 18, 2011, describes an investigation of FPE Stab-Lok breakers. Three points from it are worth knowing:

• CPSC testing confirmed that certain FPE breakers failed some Underwriters Laboratories (UL) calibration tests.
• CPSC closed the investigation because the data available "does not establish that the circuit breakers present a serious risk of injury to consumers."
• The closure was made "without making a determination as to the safety of FPE circuit breakers."

In plain terms: CPSC looked, found some test failures, could not establish a serious risk from the data it had, and stopped without ruling either way on safety. You can read the full release on the CPSC website.

What that record does and doesn't mean

The CPSC record does not say that FPE panels are safe, and it does not say they are unsafe. It is an investigation closed without a determination. That's why the useful next step isn't to rely on a forum thread or a sales pitch. It is to have a licensed electrician look at your specific panel: its condition, its breakers, its capacity and how it has been modified over the years.

Be wary of anyone, in either direction, who overstates what CPSC concluded. If a quote leans on claims about the brand, ask the contractor to point you to the source.

What about Zinsco?

We found no CPSC statement or action on Zinsco panels, so we make no safety claim about them. Zinsco is an older panel brand that many electricians recommend having evaluated, mostly because of its age. As with FPE, the practical answer is an evaluation of your actual panel by a licensed electrician.

Why an older panel is worth evaluating anyway

Brand aside, there are ordinary reasons to have an older panel looked at:

• Age and condition. Decades of additions, replaced breakers and do-it-yourself changes add up.
• Capacity. A panel that was fine for a 1970s house may be short on space or amperage for a heat pump, induction range or Level 2 EV charger. The City of Fort Collins' Home Electrification page suggests consulting an electrician to assess your panel for added electric loads.
• Buying or selling. A home inspector may flag a panel brand and recommend evaluation by a licensed electrician. Our page on electrical inspections for home buyers and older homes covers that kind of visit.

Fort Collins has a fair amount of housing from the decades when these brands were sold. In the Census Bureau's American Community Survey (2024 5-year), 30.6% of Fort Collins homes were built before 1980, and in ZIP code 80521 (which covers most of Old Town's west side and the CSU area) the median year built is 1978. We don't know of any count of FPE or Zinsco panels locally.

Typical costs if you decide to replace

Typical national ranges from published cost guides (2025–2026) — estimates, not quotes; no Fort Collins-specific source was published.

Two Fort Collins details affect the real number. First, the City says electrician bids usually do not include Fort Collins Utilities' service-upgrade costs, so ask whether yours does; our post on utility service-upgrade costs explains that line item. Second, if the new panel is 200 A or more and is paired with an electrification project such as a heat pump or Level 2 EV charger, you may qualify for an Efficiency Works panel rebate; see our rebate guide and check efficiencyworks.org before you sign. Full prices and a calculator are on our electrician cost page.

Permits for panel work in Fort Collins

Inside city limits, the City of Fort Collins Building Services issues electrical permits and inspects. Panel and service work typically needs a permit, and the contractor normally pulls it before work starts. Outside the city, the permit office depends on where you live: Loveland, Windsor, Wellington, Timnath and unincorporated Larimer County each have their own process. Our Fort Collins electrical permit guide has details. This is general information, not legal advice.

For more on the work itself, see electrical panel upgrades in Fort Collins and, if you're planning a charger, do you need a panel upgrade for an EV charger?

Before you hire

• Confirm the contractor's Colorado electrical contractor registration and its master electrician's license with the Colorado Division of Professions and Occupations (DORA) license lookup.
• Inside Fort Collins, confirm the contractor is registered with the City.
• Ask who pulls the permit, and make sure it is pulled before work starts.
• Ask for proof of insurance.
• Get a written quote that says whether the utility's service-upgrade costs are included.

Source: U.S. Consumer Product Safety Commission, Commission Closes Investigation of FPE Circuit Breakers (1983, revised 2011). No CPSC statement on Zinsco was found.