What Is a Heavy-Up? Electrical Service Upgrades Explained
A heavy-up is an electrical service upgrade that raises how much power your home can draw, usually from 100 to 200 amps. When you need one, how the process works with your electrician and utility, and what it typically costs.
Still stuck after this guide? You can ask an electrician online — see pricing, expert credentials and common questions first.
What Is a Heavy-Up?
A heavy-up is an electrical service upgrade: it increases the total amperage your home can draw from the utility, most often from 100 or 150 amps to 200 amps. The term is common in the Washington, DC, Maryland and Northern Virginia area, where utilities such as Pepco and Dominion Energy serve many homes, but the work is the same job electricians elsewhere simply call a service upgrade.
A heavy-up usually replaces more than the breaker panel. It typically includes a new main panel, a new meter base, new service entrance cable and, on overhead service, a new mast or weatherhead, plus grounding brought up to current code. If the larger service needs it, the utility may also upgrade the service drop or the transformer that feeds your home. Because the utility has to disconnect and reconnect the service, it is always part of the process.
A same-size panel replacement is not a heavy-up, because it does not add capacity. Our electrical panel upgrade guide compares panel replacement, service upgrades and subpanels side by side.
When Do You Need a Heavy-Up?
You need a heavy-up when the electrical loads you want to run add up to more than your current service can safely supply. Common triggers:
- A Level 2 EV charger, which is a large continuous load on a 240-volt circuit
- Switching to a heat pump or electric heat, especially if you are replacing a gas furnace
- An electric range, induction cooktop or electric tankless water heater
- A home addition, finished basement or accessory dwelling unit
- A hot tub, pool equipment or workshop tools
Whether you actually need one is decided by a load calculation, which electricians do using the method in the National Electrical Code (NEC Article 220). Sometimes the calculation shows your existing service can handle the new load, or that a load management device (which limits an EV charger when other big appliances are running) avoids the upgrade. Ask for the load calculation before you agree to a bigger service.
Signs Your Home May Need More Service
A main breaker rated 100 amps or less, or a fuse box instead of breakers. A panel with no open spaces, or many doubled-up "tandem" breakers squeezed in to make room. Lights that dim noticeably when the air conditioner, dryer or well pump starts. A main breaker that trips when several large appliances run at once. Plans to add any of the loads above. Some of these signs point to a worn or faulty panel rather than too little capacity, so have a licensed electrician look at the whole system. If the panel is hot, buzzing, smells like burning or shows scorch marks, that is a safety issue: call an electrician promptly and do not wait to plan an upgrade.
How a Heavy-Up Works, Step by Step
- Assessment and quote. A licensed electrician checks your existing service, does a load calculation and recommends a size (200 amps is the most common choice for a home).
- Permit. The electrician pulls an electrical permit from your city or county. Service upgrades require a permit and inspection essentially everywhere.
- Utility request. The electrician or homeowner submits a service upgrade request to the utility. The utility reviews whether its service drop, underground lateral or transformer can carry the new load, and schedules its part of the work.
- Installation day. The utility disconnects power (or pulls the meter) so the electrician can replace the meter base, service entrance cable and panel and move every circuit to the new panel. Expect the power to be off for most of the day.
- Inspection. The local electrical inspector checks the new service. Many utilities will not reconnect a new service until it has passed or been released by the inspector.
- Reconnection. The utility reconnects the service and sets the meter, and any utility-side upgrades are completed.
The exact order and who files what varies by utility and jurisdiction, so ask your electrician to walk you through the local process before work starts.
How Much Does a Heavy-Up Cost?
For a typical 100- to 200-amp heavy-up, national cost guides put the price in the low thousands: Fixr lists about $1,800 to $4,500 for a 200-amp upgrade. Published estimates from electricians in the DC, Maryland and Virginia area are often higher, commonly in the $3,500 to $6,000 range and more for complex jobs, because labor and permit costs there are above the national average. Moving to 400-amp service costs considerably more.
What pushes the price up:
- Relocating the meter or panel, or a long cable run between them
- Underground service that needs trenching or new conduit
- Code corrections the inspector will require, such as grounding and bonding, or AFCI and GFCI protection
- Utility charges if the service drop or transformer must be upgraded (policies vary by utility)
- Permit fees, and drywall or siding repair after the work
Get at least three written quotes from licensed electricians and confirm each one includes the permit, inspection, utility coordination and any patching, since some quotes cover the panel only.
How Long Does a Heavy-Up Take?
The electrician’s on-site work usually takes one day, occasionally two for complicated jobs. The full project, from signing the contract to having the new service energized, often takes several weeks because of permit processing, inspection scheduling and the utility’s own lead time. If the utility has to upgrade its equipment, it can take longer, and some homeowners in the DC area report waiting months for utility line work. Ask your electrician what the current utility lead time is in your area before you schedule an EV delivery or a heat pump install that depends on the new service.
Not sure whether your home needs a heavy-up or whether a quote is reasonable? You can describe your panel and plans on our electrician help page to get a second opinion before you sign.
Pro Tips
Frequently Asked Questions
What is a heavy up electrical?
A heavy-up is an electrical service upgrade that increases the total amperage your home can draw from the utility, most often from 100 or 150 amps to 200 amps. It usually involves a new panel, meter base and service entrance cable, plus a permit, an inspection and coordination with the utility.
Is a heavy-up the same as a panel upgrade?
Not always. A heavy-up always increases your service capacity. A panel replacement can be the same size as the old panel, which adds breaker spaces or fixes a faulty panel but does not let you draw more power. A heavy-up usually includes a new panel as part of the job.
How much does a heavy-up cost?
National cost guides such as Fixr put a 200-amp upgrade at about $1,800 to $4,500. Electricians in the DC, Maryland and Virginia area often publish higher estimates, commonly $3,500 to $6,000 or more, depending on meter location, underground service and code corrections.
How long does a heavy-up take?
The installation itself is usually one day with the power off for most of it. The whole process, including the permit, inspection and utility scheduling, often takes several weeks and can take longer if the utility needs to upgrade its own equipment.
Do I need a heavy-up for an EV charger?
Not always. Many homes with 200-amp service can add a Level 2 charger without an upgrade, and some 100-amp homes can too with a lower-amperage charger or a load management device. A load calculation by a licensed electrician tells you which applies to your home.
