Do You Need to Upgrade Your Electrical Panel to Install an EV Charger?

As electric vehicles become more common, one of the first questions homeowners ask is whether their electrical panel needs to be upgraded before installing an EV charger.

The short answer is: sometimes — but not always.

Many homeowners are surprised to learn that a panel upgrade isn’t automatically required. The real answer depends on how much electrical capacity your home already uses and how much additional load an EV charger will add.

This article explains how that determination is made and what factors actually matter.

1. Why EV Chargers Use More Power Than Most Homeowners Expect

EV chargers draw a significant amount of electricity compared to most household devices. A Level 2 charger, which is the most common option for home charging, typically operates on a 240-volt circuit and can add a continuous load for several hours at a time.

Because EV charging is considered a continuous load, electrical code requires that the home’s electrical system be evaluated carefully before installation.

That evaluation is what determines whether the existing panel can safely handle the additional demand.

2. What Actually Determines Whether Your Panel Can Handle an EV Charger

Despite what many people assume, the answer isn’t based on panel size alone.

A 100-amp or 200-amp panel does not automatically mean “yes” or “no.”

Instead, the decision is based on:

• How much power your home already uses

• What major electrical loads are present (electric heating, A/C, range, dryer, etc.)

• How those loads are used over time

• How much capacity remains for a new continuous load

This is why two homes with the same panel size can have completely different outcomes.

3. The Role of Load Calculations (And Why They Matter)

To determine whether a panel upgrade is required, electricians perform a load calculation.

In Ontario, one approved method involves reviewing the home’s previous 12 months of electrical usage data, provided by the hydro supplier. This historical data gives a realistic picture of how much power the home actually uses — not just what it could use on paper.

The Electrical Safety Authority (ESA) accepts this method when adding new electrical loads, including EV chargers.

Using real usage data often provides a clearer and more accurate assessment than relying on theoretical maximums alone.

4. When a Panel Upgrade Is Commonly Required

A panel upgrade is more likely when:

• The home already has several large electrical loads

• Electric heating or electric water heating is present

• The panel is older or limited in capacity

• Existing circuits are already near their allowable limits

• The load calculation shows insufficient remaining capacity

In these cases, upgrading the panel helps ensure the EV charger can operate safely without overloading the system.

5. When a Panel Upgrade May Not Be Necessary

Many homeowners are surprised to learn that a panel upgrade is not always required.

A panel may be sufficient if:

• The home’s historical usage is relatively low

• Large electrical loads are limited or well-balanced

• The load calculation shows adequate remaining capacity

• The EV charger size can be matched appropriately to the system

This is why a proper evaluation is so important before assuming an upgrade is needed.

6. Common Misconceptions About EV Charger Installations

One of the biggest misconceptions is that every EV charger requires a 200-amp panel upgrade.

In reality, EV charger installations should be based on:

• Actual usage

• Code-approved calculations

• The specific charger being installed

• The home’s overall electrical profile

Skipping this step can lead to unnecessary upgrades — or worse, unsafe installations.

7. Older Homes in Whitby & the Durham Region

In Whitby and across the Durham Region, many homes were built before electric vehicles were even a consideration. These homes often have:

• Smaller original panels

• Electrical systems that have been added to over time

• A mix of modern and older wiring

That doesn’t automatically mean an upgrade is required — but it does mean a proper assessment is essential before adding a new EV charging load.

Final Thoughts

There is no one-size-fits-all answer when it comes to EV charger installations.

Some homes require panel upgrades. Others don’t.

The only reliable way to know is by performing a proper load calculation using approved methods — including real historical usage data — and designing the installation around the home’s actual electrical capacity.

That approach ensures the charger operates safely, reliably, and in compliance with Ontario electrical code.