If you have been pricing an EV charger, a heat pump, or an ADU in Stockton or Tracy, someone has probably told you that you need to upgrade to 200-amp service. Sometimes that is true. Often it is not. Service size is one of the most misunderstood parts of a home electrical system, and the right answer depends on what you actually run, what you plan to add, and what is already in your panel. This guide walks through what 100A, 150A, and 200A really mean, how to spot signs you have outgrown your service, and what a real upgrade involves.
What 100A, 150A, and 200A actually mean
The amperage rating on your service is the maximum current the utility, meter, panel, and main breaker are designed to deliver continuously. It is not what you use day to day. A typical Stockton home pulls a small fraction of its rated service most hours, and peaks on summer afternoons when AC, oven, and dryer happen to run together.
- 100A service: standard for most homes built in Stockton from the 1960s through the late 1990s. Enough for gas heat, gas water heater, gas range, central AC, and ordinary plug loads.
- 125A and 150A: less common, often seen after a partial upgrade. A reasonable middle ground when 100A is tight.
- 200A: standard on new construction in Tracy, Lathrop, and newer Stockton subdivisions. Comfortable headroom for full electrification.
- 400A: rare in residential — large custom homes or homes with detached shops.
Signs you have outgrown your service
A working 100A panel is not automatically obsolete. What matters is the gap between what your service can deliver and what your household demands.
- Planning a Level 2 EV charger — see EV charger installation.
- Converting from gas to a heat pump for HVAC or water heating.
- Running two or more AC condensers.
- Planning a kitchen remodel with induction cooking and a double oven.
- Adding an ADU or junior ADU.
- Existing panel full, all tandem breakers, or a problem brand like Federal Pacific.
When you do NOT need to upgrade
Most working 100A homes in Stockton are fine. If your panel is a modern brand in good condition, your main has never tripped, your AC and dryer run together without issue, and you are not planning major electrification, an upgrade is usually unnecessary. A licensed electrician can perform a load calculation that often shows a 100A or 125A service has more room than people assume. A smart EV charger that throttles based on whole-house demand can let you add a charger without touching the service at all.
What an actual 200A upgrade involves
A residential service upgrade in Stockton or Tracy is more coordinated than a simple panel swap.
- Load calculation and permit application through the city or county.
- PG&E coordination for a temporary disconnect and reconnect.
- Replacement of meter socket, main panel, main breaker, and grounding system.
- Inspection by the building department before PG&E reconnects.
- Incidental mast, weatherhead, or grounding repairs on older homes.
Frequently Asked Questions
Is Can Do It Electrical a licensed contractor?
No. Can Do It Electrical is a referral and job-coordination service connecting Stockton homeowners with independent licensed electricians. The permit, work, and warranty are held by the licensed contractor who performs the upgrade.
How much does a 200-amp service upgrade cost?
For a typical single-family home, residential upgrades from 100A to 200A usually fall in the $2,500 to $4,500 range. Underground services, long meter-to-panel runs, mast replacement, or significant grounding work can push higher.
Can I add an EV charger without upgrading to 200A?
Often yes. A load calculation tells you for sure. Many 100A and 125A homes accommodate a Level 2 charger, especially with a smart charger that throttles when the rest of the house is drawing heavily.
How long does the upgrade take?
Physical work is usually one day. The full timeline including permits and PG&E scheduling runs two to four weeks. Power is off only during the work day itself.
Will I notice anything different after the upgrade?
Day to day, no. Your bill does not increase simply because the service is rated higher — you still pay for energy you actually use. What changes is headroom for EV charging, heat pumps, induction, or ADU feeders.
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The Can Do It Electrical Team
Written by the Can Do It Electrical team. Can Do It is a Stockton-based electrical referral service — we connect Central Valley homeowners and businesses with licensed, vetted local electricians and write about the electrical patterns we see in real Stockton-area jobs.
