Amperage is one of the most useful numbers to understand about your home’s electrical system, because it tells you how much power your panel can safely deliver. If you are thinking about adding an EV charger, upgrading appliances, or finishing a basement, knowing your panel’s amperage rating is the first step. The good news is that checking it is usually simple.

Here is what amperage means and how to find your panel’s rating.

What amperage is

Amperage, measured in amps, is the rate at which electricity flows through a circuit. A common way to picture it is water in a pipe. Voltage is the pressure pushing the water, amperage is how much water is flowing, and wattage is the total power delivered. In fact, watts equal volts times amps, which is why amperage matters so much: it sets the ceiling on how much power your system can carry at once.

Every part of your electrical system has an amperage limit, from individual circuits to the main panel that feeds the whole house.

What your panel’s amperage rating means

Your panel’s amperage rating is the maximum current your electrical service can safely handle. Common residential ratings are:

• 60 amps. Found in older homes and often undersized for modern needs.
• 100 amps. Common in many homes and adequate for modest usage.
• 150 amps. A middle capacity.
• 200 amps. The most common rating for newer and updated homes, and usually enough for EV charging, electric appliances, and additions.

As homes add more electric loads, upgrading to 200 amps has become a common project.

How to check your panel’s rating

There are a few easy ways to find your rating, and most do not require removing any covers:

• Read the main breaker. Open the panel door and look at the large breaker, usually at the top or bottom, that controls all the others. The number stamped on its handle, such as 100 or 200, is typically your service amperage.
• Check the panel label. The manufacturer’s label inside the door often lists the panel’s ratings.
• Look at the documentation. Home inspection reports or electrical permits from past work may state the service size.

If your panel has no single main breaker, such as some older split-bus panels, the rating can be harder to determine, and it is best to have an electrician confirm it.

A quick safety note

You can safely open the outer panel door and read the main breaker’s number. Do not remove the inner cover, called the deadfront, since that exposes live parts. If you cannot find the rating from the main breaker or label, an electrician can determine it safely.

Why your panel’s rating matters

Knowing your amperage helps you plan. It tells you whether your home can support new loads like an EV charger, a heat pump, a hot tub, or a kitchen remodel, or whether you may need more capacity. Signs your rating may be limiting you include breakers that trip often, no open slots for new circuits, or an older 60 or 100 amp service when you want to add major appliances.

Amperage is the rate of electrical flow, and your panel’s amperage rating is the maximum your service can safely carry, commonly 100, 150, or 200 amps in homes. You can usually find it by reading the number on your main breaker or the label inside the panel door. If you are planning to add significant electrical loads, knowing this number tells you whether your panel is ready or whether an upgrade makes sense.

Stella Electric evaluates and upgrades electrical panels for homeowners across the Baltimore area and throughout Maryland, with flat-rate pricing and no overtime charges. If you are not sure of your panel’s capacity or want to add new loads, we can check it and advise. Financing is available on qualifying projects.