Cost to upgrade an electrical panel to 200 amps in San Antonio, step by step

If you are looking up the cost to upgrade an electrical panel to 200 amps, something has likely pushed you there: an EV in the driveway, an AC contractor who says your panel cannot carry the new system, an addition on the drawings, or an insurance letter about an old 100-amp panel. The stake is real. Do it right and the house has room for the next twenty years of loads. Do it halfway and you end up with a new panel on an old service that still cannot carry what you need.

This guide walks through a 100 amp to 200 amp upgrade the way it actually happens in San Antonio: the load calculation, the permit, the CPS Energy disconnect and reconnect, the meter base and service entrance, what can push the price, and how long it takes from your first call to the lights coming back on.

A 200 amp service upgrade is more than a new panel

The panel is the box with the breakers. The service is everything that brings power to it: the utility drop or underground lateral, the mast and weatherhead on overhead services, the meter base, the service entrance conductors, the main breaker and the grounding system. A panel replacement swaps the box and keeps the service. When you upgrade to 200 amp service, the parts that limit the house to 100 amps have to be resized, and that usually means most of the service.

That is the main reason the two jobs are priced differently. If your service is already 200 amps and only the panel is failing or obsolete, our guide to electrical panel replacement cost is the one to read. If the house is on 100 amps or less and you need more power, keep reading here.

Signs you need to upgrade to 200 amp service

• You are adding a Level 2 EV charger and the load calculation shows no room for it on the existing service.
• You are replacing a gas furnace or an old AC with a heat pump or a larger system.
• An addition, garage conversion or casita will add heating, cooling and kitchen loads.
• Your insurer or a buyer's inspector has flagged an old 100-amp or smaller service on the TREC inspection report.
• The main breaker trips, or lights dim noticeably when the AC compressor starts, and the panel itself has been ruled out.
• The panel is full, and adding a subpanel would only spread an already maxed-out service across more breakers.

None of these alone proves you need 200 amps. A full panel on a lightly loaded house may only need a subpanel, and some EV installs fit on 100 amps with load management. That is why the first step is a calculation, not a sales pitch. If you are adding a charger, our guide to EV charger panel capacity shows how that check works.

Step one: the load calculation

A load calculation adds up what the house uses: square footage, the cooking appliances, the dryer, the water heater, the HVAC equipment, and anything you plan to add. It applies the demand factors the electrical code allows, because not everything in a house runs at full power at the same moment. The result tells you whether the existing service is enough, whether 200 amps is enough, or whether a larger service is worth discussing.

Two things make the calculation useful. It has to include what you intend to add, not only what you have today, and it has to be written down so the permit, the estimate and your own planning are all working from the same numbers. If you are planning an EV charger now and a pool or a heat pump in a few years, say so up front.

Step two: the permit with Development Services

A service upgrade is permitted work in every jurisdiction we serve. Inside San Antonio, the electrical permit is issued by the Development Services Department and pulled by a licensed electrical contractor. Wattsmith Electric is licensed by TDLR under TECL 41806, and the permit is part of our flat price. We file it, schedule the inspection and meet the inspector. Our guide to electrical permits in San Antonio covers the process in more depth, including how it works in the suburban cities around the county.

Step three: CPS Energy disconnect and reconnect

You cannot safely replace a meter base or service entrance conductors with the utility side energized, so a service upgrade means coordinating with CPS Energy. The sequence is straightforward once you have done it many times:

• We schedule the work day and arrange the disconnect with CPS Energy so the service is dead when the old equipment comes out.
• The new meter base, service entrance conductors, panel and grounding go in that day.
• The city inspector inspects the new service. Once it passes, the release goes to CPS Energy.
• CPS Energy reconnects the service and sets the meter, and the house is back on permanent power.

CPS Energy also decides whether its own side needs work. On an overhead service, the drop from the pole may need to be replaced for the larger service. On an underground service, the utility side of the lateral is the utility's call. When that applies, it is scheduled on CPS Energy's calendar, and we tell you at the estimate whether we expect it.

Step four: the meter base and service entrance

On a typical San Antonio home built with a 100-amp service, the meter base is rated for that service and the conductors from it to the panel are sized for 100 amps. Both get replaced. On an overhead service, the mast and weatherhead that carry the conductors up to the drop are often replaced at the same time, because an older mast may be too small for the new conductors or no longer sound. The new equipment has to meet CPS Energy's published requirements for meter equipment as well as the electrical code.

If the meter, mast and weatherhead are unfamiliar terms, our explainer on the meter loop, mast and weatherhead walks through each piece and who owns what.

What the cost to upgrade an electrical panel to 200 amps includes

For the standard job, our flat-rate book lists the Service upgrade, 100A to 200A task, from $5,369. That covers the new 200-amp panel and main breaker, the circuits moved over and labeled, the service conductors resized, the permit and the inspection. You see the price and approve it before work starts. Starting price. Your tech confirms the final number on site before any work.

The book price assumes a typical house with typical service equipment, which is why the cost to upgrade an electrical panel to 200 amps is confirmed on site before you approve it. What we look at on the visit is whether your service has any of the conditions below, because those are the items that move the 100 amp to 200 amp upgrade cost from one job to the next.

What can push the price: meter can, mast and grounding

The meter can is the first. On many homes the existing meter base is rated below 200 amps, rusted through, or no longer accepted by the utility. Replacing it is often part of the upgrade, and if the meter base and its conductors need more than a standard swap, it is priced as its own line.

In our book, replacing the meter base on its own is the Meter can replacement task, from $1,709. The higher tiers include replacing the service entrance cable and rebuilding the mast, which is what an older overhead service often needs. Starting price. Your tech confirms the final number on site before any work.

The mast comes second. A mast that is bent, rusted at the roof line, too short for the clearance the drop needs, or too small for the new conductors has to be rebuilt. Where the roof has to be opened and flashed around a new mast, the estimate says so.

Grounding is third. Many older San Antonio homes have a single ground rod, a corroded clamp, or a grounding conductor that was never sized for a larger service. A 200-amp service needs a grounding electrode system that meets current code, and the inspector checks it.

Where the grounding needs to be brought current, our book lists the Grounding system upgrade task, from $879. On many upgrades this is part of the scope from the start, and the estimate says so before you approve it. Starting price. Your tech confirms the final number on site before any work.

Other items that come up less often: a panel location that no longer meets clearance requirements and has to move, aluminum branch circuits that need proper terminations when they land in the new panel, and gas piping that needs bonding. Each one is named and priced before work starts. Nothing is added after the fact.

You can compare these items against the published book on our pricing page. If you would rather have us look first, call us and we will tell you over the phone whether a visit is needed before a firm number.

Timeline from first call to power back on

• First call. We ask what you are adding, the age of the house and whether the service is overhead or underground. A photo of the meter and the open panel helps.
• Site visit. The technician checks the meter base, mast, grounding and panel location, runs the load calculation and gives you a flat price.
• Approval and permit. Once you approve, we file the permit with the city and schedule the work day with CPS Energy.
• Work day. Power goes off in the morning, the new service goes in, and the work is ready for inspection the same day in most cases.
• Inspection and reconnect. After the city inspection passes, the release goes to CPS Energy and they restore permanent service.

Most of the waiting is permit and utility scheduling, not construction. The outage itself is usually a single working day. If CPS Energy has to replace its own drop or work on the underground side, that adds its own scheduling, and we tell you when we expect it.

Plan for the outage. Refrigerators and freezers hold their temperature for a working day if the doors stay closed. Anyone at home who depends on powered medical equipment should tell us at the first call so the work day is planned around it.

Why the 200 amp upgrade is worth doing once, properly

A service upgrade is a job you do once for the life of the house. Done properly, it gives you room for an EV charger, a heat pump and whatever the next owner adds, and it clears an item that insurers and buyers ask about. The way to get there is a flat price that names every piece of the service before anyone touches it, a permit, and an inspection that the utility relies on before it restores power.

Read what goes into this work on our panel upgrades page, check whether financing fits your timing, and when you are ready, call us to schedule the visit. We handle the permit, the CPS Energy coordination and the inspection, so the only thing you schedule is the day the power is off.