Circuit Breakers Compatibility Chart: 2025 Guide

Finding the right circuit breaker for your electrical panel is crucial to ensure safety, performance, and code compliance. Not all breakers are interchangeable across different panel brands – each manufacturer designs its breakers and panels as a matched system. Using a breaker that isn’t made or approved for your panel can result in poor connections, overheating, or even fire hazards. This 2025 guide provides an updated circuit breaker compatibility chart and detailed insights for all major brands. Whether you’re looking for a Siemens breaker compatibility chart, a GE breaker compatibility chart, or cross-reference info on Westinghouse compatibility chart data, this guide will help you find the right replacement. We’ll explain compatibility principles, highlight manufacturer-specific listings, and give you tips to safely choose the proper breaker for your panel.

Understanding Breaker Compatibility Basics

Why compatibility matters: Circuit breakers are not universal swaps – even if a breaker of a different brand seems to fit physically, it may not make proper electrical contact with the bus bar or may not latch correctly. Manufacturers use unique designs and connection mechanisms, so mismatched breakers can loosen or fail to trip properly under fault conditions. In short, a breaker must be listed or classified for use in a given panel to guarantee safe operation.

UL Listed vs. Classified: When a breaker is the same brand and type specified for the panel, it is UL listed for that panel (part of the panel’s original safety certification). UL-classified breakers, on the other hand, are special replacements that have been tested by Underwriters Laboratories to be safe in other brands’ panels. For example, Eaton’s UL-classified breakers have been tested to be interchangeable with breakers from other leading manufacturers – effectively allowing one brand’s breaker to be safely used in a competitor’s panel, as long as it is the correct classified model. These options provide flexibility, but each classified breaker is only approved for specific panel models (as indicated on its documentation).

Panel labeling and instructions: Always start by checking the inside of your panel door for a label or chart indicating which breaker types or model numbers are approved. Panel manufacturers typically list the exact breaker series (and sometimes specific part numbers) that are compatible. As a rule of thumb, follow the panel manufacturer’s instructions first. If the label is faded or missing, identify the breaker type by examining the existing breakers and use the same type as replacements. Ensure the new breaker has the same mounting style and fits snugly in the panel before restoring power. Only when a breaker is listed on the panel labeling – or is a UL-classified substitute for that specific panel – can you be confident it will function correctly and safely.

Compatibility Chart and Cross-Reference Overview

To make sense of breaker interchangeability, experts often refer to circuit breaker compatibility charts. These charts show which breaker models from one manufacturer can replace those of another, based on UL classification and matching electrical specifications. Below is an example of a cross-reference chart for Eaton’s Type CL series breakers (1-inch wide classified replacements) illustrating how one breaker model can be listed for use in multiple panel brands:

In this chart, each column under a panel brand lists that brand’s equivalent breaker model number for a given Eaton CL breaker. For example, a single Eaton CL breaker model might correspond to breaker part numbers from Siemens, Murray, GE, Square D, and others, indicating a high degree of interchangeability. Eaton also produces Type CHQ breakers (3/4″ wide) that are UL-classified for Square D’s QO panels, and Siemens offers Type QD classified breakers as direct replacements for Square D QO models.

It’s important to use these charts or manufacturer cross-reference guides when you need to find an alternative breaker. Never assume that a breaker is compatible based solely on physical fit. Always confirm through a compatibility chart or official documentation that the breaker is either the exact model the panel accepts or a UL-classified substitute.

Siemens Breaker Compatibility Chart

Siemens panels (including former ITE and Gould panels) are designed to use Siemens breakers of the matching type (commonly Type QP for most residential panels). Siemens acquired the Murray line, so modern Siemens breakers directly replace old Murray breakers on a one-to-one basis. In fact, Siemens announced a phase-out of the Murray brand in 2019–2020, assuring that equivalent Siemens products would cover all Murray breaker and panel needs. If you have a Murray electrical panel, you should now use the appropriate Siemens breakers recommended for that panel (check Siemens’s documentation for the matching type number).

Siemens breakers are sometimes considered the “universal” fit by electricians because their form factor often allows them to plug into many other brand panels. For example, Siemens QT series twin breakers can physically fit in certain GE, Murray, Challenger, Arrow Hart, and Westinghouse panels. This mechanical versatility is convenient, but it does not guarantee electrical compatibility or code compliance. Officially, you should only use a Siemens breaker in another panel if it is explicitly listed for that panel or is a UL-classified substitute.

For Siemens panels themselves, you have options beyond Siemens-made breakers in some cases. Eaton’s CL series breakers (Cutler-Hammer’s classified line) are UL-classified for Siemens/ITE panels and can serve as safe replacements. These Eaton CL breakers have been tested to meet Siemens panel specifications, providing a compatible alternative if Siemens breakers are unavailable. Additionally, Siemens manufactures Type QD classified breakers intended as replacement breakers for Square D QO panels. In other words, even Siemens produces a breaker for a competitor’s panel – but only those specially designated models can be used in the other brand’s equipment.

GE Breaker Compatibility Chart

General Electric (GE) panels (now part of ABB) normally require GE’s own breakers (such as the THQL series for full-size breakers or THQP for half-size slim breakers). GE breakers are designed for GE load centers, and using the correct type ensures a proper fit on the bus. Officially, you should stick to the breaker models listed on your GE panel’s label (e.g. types THQL, THHQL, etc., as indicated inside the panel).

That said, there are UL-classified breakers that can be used in GE panels as alternatives. Eaton’s Type CL breakers are one such option – they have been tested to be interchangeable with a range of other brands including GE. In Eaton’s compatibility chart, for example, an Eaton CL breaker can replace certain GE breaker models (covering common amperages in 1- and 2-pole configurations) safely. If you cannot source a genuine GE breaker, a properly classified replacement (with labeling indicating it’s suitable for GE panels) can be used while still meeting code.

Conversely, can GE breakers go into other brand panels? In general, GE breakers should only be used in panels that explicitly accept them. While some GE breakers might appear to fit in a Siemens or Square D Homeline panel, they are not listed for those panels and likely will not seat correctly on the bus – which can cause a poor connection or overheating risk. One source notes that a GE breaker can be compatible with panels from Siemens, Square D, and Eaton – but this implies the use of properly classified breakers or panel-specific approvals, not a blanket rule. Outside of a UL-classified context, you should avoid mixing GE breakers into non-GE panels.

Westinghouse Breaker Compatibility Chart

Westinghouse electrical panels are an older brand (Westinghouse’s breaker division was acquired by Cutler-Hammer, now Eaton). If you have a Westinghouse panel, the breakers it uses are generally the same design as those sold under the Bryant or Cutler-Hammer Type BR series. In fact, many Westinghouse panels were labeled to accept Type BR breakers – “BR” originally stood for Bryant, a company Westinghouse had acquired. Today, Type BR breakers are manufactured by Eaton and are directly compatible replacements for the original Westinghouse/Bryant breakers. For example, if your panel label says to use a Bryant BR20 or BR30 breaker, an Eaton BR20 or BR30 is the correct modern breaker to use.

Because of this legacy, there is broad interchangeability among Westinghouse, Bryant, Challenger, and Eaton/Cutler-Hammer BR breakers. These brands all used similar 1-inch plug-in breaker styles. An Eaton Type BR breaker will fit and function in many older panels from those brands (as long as the panel is designed for Type BR or equivalent). Likewise, UL-classified replacement charts include Westinghouse (and its synonymous Bryant/Challenger family) as compatible with Eaton’s classified breakers. Essentially, Eaton carried forward the Westinghouse design, so using an Eaton breaker in a Westinghouse panel is often not just compatible but the recommended solution – since Westinghouse-branded breakers are no longer produced except as old stock or reconditioned units.

Note that most Westinghouse residential panels used the BR-style breakers (the larger 1-inch type), not the smaller Cutler-Hammer CH breakers. If your panel required CH breakers, it would explicitly say so on the label. In summary, for a Westinghouse panel you should use breakers from the Eaton/Cutler-Hammer Type BR series, which are the direct descendants of the original Westinghouse/Bryant line. Always check the panel’s instructions – if it says “Use only Bryant BR…” that is effectively instructing you to use Eaton BR breakers today. This continuity ensures your replacement breakers will seat properly and maintain the panel’s UL listing.

Square D Breaker Compatibility (Homeline vs. QO)

Square D (a Schneider Electric brand) produces two major residential breaker lines: Homeline (HOM) and QO. It’s critical to note that these two are not even compatible with each other despite being the same brand – a Homeline breaker will not properly fit in a QO panel, and vice versa, due to different bus bar designs. Square D Homeline and QO breakers are specifically designed for their respective load centers and service equipment. They meet high ANSI/UL safety standards and are intended to be used exclusively in Square D panels.

Square D is known for a proprietary bus stab shape, especially in QO panels (the QO series uses a unique clip design). No other standard breaker will physically fit a Square D QO panel, which makes QO one of the most restrictive systems. Homeline panels have a more generic-looking slot, but still, Square D specifies using only Homeline breakers in those panels for full compliance. The company has historically warned against using any competitors’ breakers in their panels, citing National Electrical Code 110.3(B) – which requires following the equipment listing/labeling – and pointing to potential fire hazards if breakers don’t seat correctly. Using a non-Square D breaker in a Square D panel can void the panel warranty and is often considered a code violation by inspectors.

Despite Square D’s strict stance, there are UL-classified breakers made by other manufacturers to fit Square D panels. For Homeline panels, Eaton’s CL series breakers are UL-classified for use as replacements (covering common ratings like 15–50A). For QO panels, Eaton offers the CHQ series classified breakers and Siemens offers the Type QD classified breakers – both specifically designed to interface with Square D QO bus bars. These breakers have been tested to trip properly and connect safely in Square D equipment, and Underwriters Laboratories permits their use in the approved panels. However, using them can be contentious: Square D may refuse warranty claims if a failure involves a non-OEM breaker (although legally they cannot void a warranty simply for using a UL-approved part). Many professionals will only use Square D’s own breakers in Square D panels to err on the side of caution.

Bottom line: For Square D Homeline or Square D QO panels, the best practice is to use the matching Square D breakers. Only consider a UL-classified alternative if you have no access to the OEM breaker and you ensure the replacement model is explicitly listed for your panel. Always adhere to the instructions on the panel label. If you do use a classified breaker in a Square D panel, it’s wise to keep the breaker’s documentation (which shows the UL-classified compatibility) in case there are questions during an electrical inspection.

Eaton / Cutler-Hammer Breaker Compatibility

Eaton (Cutler-Hammer) panels can be a bit complex because Eaton produces breakers for its own legacy panels and makes UL-classified breakers for use in other brands’ panels. If you have an Eaton (or older Cutler-Hammer) panel, the first step is to identify the panel’s breaker type:

• Type CH – These breakers are 3/4-inch wide per pole, usually with a distinctive tan (beige) handle. They fit Cutler-Hammer CH-series panels. Only Type CH breakers (by Eaton) are listed for CH panels – they are not interchangeable with any other type.

• Type BR – These are 1-inch wide breakers with typically black handles. Eaton’s BR series (the design acquired from Bryant/Westinghouse) is essentially the same format used by Bryant, Westinghouse, and many Challenger panels. If your panel uses BR breakers, it might be labeled as such (or as “Type C”), and you should use Eaton Type BR breakers in that panel.

It’s crucial not to mix Eaton’s own CH and BR breakers – a BR breaker will not properly connect in a CH panel, and vice versa. The panel labeling will indicate which type is required. For example, an older Cutler-Hammer panel might say “Use Type CH breakers only,” whereas a panel from the Bryant/Westinghouse lineage will list Type BR or compatible part numbers.

When it comes to cross-brand compatibility, Eaton is a leader. Eaton manufactures UL-classified breakers(the CL series and CHQ series) that are tested to replace many competitors’ breakers. The Type CL breakers are built on the BR frame and can be used in numerous panels such as Siemens/ITE, Murray, GE, Square D Homeline, Crouse-Hinds, and more. The CHQ breakers are made to fit Square D QO panels (mimicking the QO form factor). Eaton provides detailed documentation listing exactly which panel models these classified breakers are approved for. If you use an Eaton classified breaker in another brand’s panel, be sure to follow the instructions and verify that your panel model is on the approved list.

In an Eaton panel, you generally should stick with Eaton’s own breakers (CH or BR as specified). It’s rare to use a different brand’s breaker in an Eaton panel, except in special cases where the other breaker is explicitly listed for it. (Usually, it’s the other way around – Eaton provides breakers for other panels.) Note that Cutler-Hammer did have some older series that were rebranded or cross-listed, but any such allowance will be stated on the panel label.

Handling Obsolete or Defunct Breaker Brands

Not all panels in service today are from current manufacturers. Federal Pacific Electric (FPE) Stab-Lokbreakers and Zinsco (Sylvania) panels, for instance, were once common but have been discontinued for safety reasons. These brands are known for design flaws (for example, breakers failing to trip reliably), so you won’t find a modern manufacturer’s breaker that is officially compatible with them. In fact, many experts recommend full panel replacement for FPE Stab-Lok or Zinsco systems due to the inherent hazards.

That said, there are third-party companies (like Connecticut Electric’s “UBI” line) that produce aftermarket breakers intended to fit some obsolete panels. These breakers are UL-classified for those specific old panel types – for example, you can find UBI breakers made for Zinsco, Pushmatic, or FPE panels. However, installing these should be done with caution and typically as a temporary measure or last resort. Using a new classified breaker in an aging, problematic panel doesn’t entirely eliminate the underlying risks if the panel itself has a defective bus design.

In summary, if you have an outdated panel, try to find a UL-classified replacement breaker designed for it, but be prepared to replace the panel if safety is a concern or no reliable breakers are available. Often, upgrading an old panel (especially ones known to be unsafe, like Zinsco or FPE) is the best long-term solution.

Safety and Compliance Considerations

Using a breaker that isn’t compatible may not only pose a fire risk but also violate electrical codes. The National Electrical Code (NEC) 110.3(B) requires that any instructions included with a listed product (like the panel) must be followed. Panel manufacturers like Square D explicitly warn that installing breakers not listed for their panel violates this code and can lead to dangerous conditions. An ill-fitting breaker might only make partial contact with the bus, causing arcing or overheating – a serious hazard.

To stay compliant and safe:

• Use the specified breakers whenever possible: The breaker models specified by the panel manufacturer are the first choice for safety and reliability.

• If using UL-classified replacements, ensure they are installed exactly as directed, and keep the documentation that shows the breaker’s compatibility with your panel. UL has stated that classified breakers are acceptable for their approved panels, but you may need to show an inspector the evidence.

• Don’t mix-and-match arbitrarily: Even if two breakers look similar, subtle differences can affect performance. Only substitute a breaker if you have official guidance (panel labeling, manufacturer chart, or UL classification info) indicating it’s allowed.

• Consider warranties and insurance: Manufacturers may warn that using non-specified breakers voids the panel warranty, though legally they can’t void a warranty just for using a UL-approved part. Still, any damage caused by an improper breaker could complicate insurance claims. It’s not worth the risk to experiment – always use a breaker that is known to be compatible.

Whenever you’re unsure about compatibility, consult a licensed electrician. Professionals stay up-to-date on breaker listings and code requirements, and they can verify that your replacement choice will keep your electrical system safe and compliant. Safety should always be the top priority when dealing with circuit breakers.

FAQ: Common Circuit Breaker Compatibility Questions

Q: Can I use a GE breaker in a Siemens panel?
A: It’s generally unsafe and against code to use a GE breaker in a Siemens panel, unless that breaker is UL-classified specifically for that Siemens panel. In practice, breakers should match the panel brand. GE and Siemens breakers may look similar, but a standard GE breaker is not listed for a Siemens panel. If you can’t find a Siemens replacement, use a UL-classified breaker that explicitly lists Siemens panels (for example, Eaton’s CL series breakers are classified for Siemens panels).

Q: Are circuit breakers interchangeable between different brands?
A: Generally no, breakers are not interchangeable across different brands. Each manufacturer’s breakers have unique designs and connection methods, and they’re tested only with their own panels. You should never swap in a different brand breaker just because it fits. The only exception is when you have a UL-classified breaker that explicitly states it is approved for use in another brand’s panel. Unless you have such documentation in hand, assume breakers cannot be swapped between brands.

Q: What breakers are compatible with Square D panels?
A: Stick with Square D breakers for Square D panels. Use Homeline breakers in Homeline panels and QObreakers in QO panels – these two series are not interchangeable with each other or with any other brand. Square D does not approve other brands’ breakers in their panels. While Eaton and Siemens do make UL-classified replacements for Square D (e.g. Eaton’s CHQ series for QO panels), use those only if absolutely necessary and they are clearly labeled for Square D. It’s safest to use genuine Square D breakers in Square D equipment.

Q: My panel brand is obsolete or discontinued (e.g. Challenger, Zinsco, FPE). What can I do?
A: If your panel’s manufacturer is out of business or its breakers are no longer made, first check if there’s a UL-listed replacement breaker made for that panel. For example, many Challenger panels can use Eaton (Cutler-Hammer) Type BR breakers, because Eaton acquired that line. There are also third-party breakers made for certain old panels (like Federal Pacific or Zinsco), but use them with caution. Often, the safest long-term solution for obsolete panels – especially known problematic ones like Zinsco or FPE Stab-Lok – is to upgrade the panel to a modern unit.

Conclusion & Key Takeaways

Choosing the correct circuit breaker for your panel is vital for safety and compliance. Always identify your panel’s brand and model, and use breakers that are listed (or properly classified) for it. We’ve seen that each major manufacturer – whether it’s Siemens, GE, Westinghouse (Eaton), Square D, or others – has specific compatibility rules. Key takeaways: stick to the panel manufacturer’s breakers whenever possible; use UL-classified cross-reference breakers only when they explicitly state compatibility with your panel; and always double-check panel labeling and the breaker’s markings before installation. If a breaker brand is discontinued or you’re uncertain about a substitution, consult a professional electrician for guidance.

By following the guidelines in this 2025 compatibility chart and guide, you can ensure your electrical system remains safe and up to code. Remember, a little diligence in selecting the right breaker can prevent big problems down the line. Stay safe, and if in doubt, reach out to a qualified electrician or reputable supplier for help in finding the correct breaker for your needs!