The most common question we hear after “how much does it cost” is “how long will I be without power?” It’s a fair concern — you’re planning your day, maybe working from home, maybe you have kids or a business to run. The honest answer for most Connecticut panel upgrades: your power will be off for roughly 4–6 hours during the electrical work itself, and the full job — including the utility reconnect — is typically done within a day.
Here’s the step-by-step picture of what actually happens, what extends the timeline, and how to plan around it.
The Typical Day-of Timeline
Every panel upgrade follows roughly the same sequence. Here’s what that looks like from arrival to restored power:
1. Arrive and assess (30–60 minutes) We confirm the scope against what we quoted — verify panel location, service entrance condition, meter base, and the path the work will take. If something has changed or looks different from the initial estimate, we address it before touching anything.
2. Utility disconnect Before the panel can be worked on safely, the utility must pull the meter or disconnect service at the street. For jobs where the utility comes out the same day, this typically happens in the morning. This is the moment power goes off in your home.
3. Remove the old panel (1–2 hours) The old panel comes out: breakers are removed, wires are labeled and pulled, the cabinet is unbolted and cleared. For panels like Federal Pacific or Zinsco, this step takes a bit longer because the breakers can be more difficult to remove cleanly.
4. Install the new panel (1–2 hours) The new panel cabinet goes in, is secured to the wall, and the main lugs or main breaker are connected to the service entrance conductors. This is the structural installation.
5. Wire circuits and install breakers (1–3 hours) Each branch circuit — every room, appliance, and dedicated circuit in the house — gets landed on the new panel. Breakers are sized correctly for each circuit. This is where the time varies based on how many circuits you have. A 100A panel with 20 circuits is faster than a 200A panel with 40 circuits.
6. Final check and call for inspection We verify all connections, check for anything that needs to be addressed before the inspector arrives, and call the inspection in. Most Connecticut towns offer same-day or next-day inspection for this type of work.
7. Inspection and utility reconnect The electrical inspector reviews the installation and signs off. The utility then reconnects service — typically within a few hours of the inspection passing, sometimes the same day.
8. Power is restored We verify the panel is operating correctly, breakers are all in normal position, and walk you through anything you need to know about your new panel.
What the Power-Off Window Actually Looks Like
For the homeowner, the power-off period is typically 4–6 hours for the electrical work itself. The utility adds a scheduling variable on top of that.
If the utility can pull the meter at the start of the job and reconnect after inspection the same day, you’re looking at a full outage of 6–10 hours. That’s a long day without power, but it’s a one-day project.
Plan for these specifics:
- No refrigeration for the duration — pull out anything that matters before we start
- No internet, no work-from-home setup — plan to be offline or work elsewhere for the day
- Extension cords for critical items — if you have medical equipment, CPAP, or anything that needs power, we can discuss sequencing or temporary solutions
- Garage doors — most modern garage doors have a manual release; know where yours is
What Extends the Timeline
Utility Scheduling
This is the single biggest variable. Connecticut has three main utilities — United Illuminating (UI), Eversource Energy, and Wallingford Electric Division — and each has its own scheduling process for disconnects and reconnects.
In many cases, utilities can accommodate same-day disconnect/reconnect if we schedule early. In others, the reconnect is scheduled for the following business day, which means your power is off overnight. We flag this during the estimate so you can plan accordingly.
Wallingford Electric is generally fastest given its smaller service territory. Eversource and UI vary by season and workload — summer tends to be slower due to higher demand.
Mast or Service Entrance Replacement
If your weatherhead mast needs to be replaced — either because it’s undersized for the new service amperage, rusted, or damaged — that adds an hour or two to the job. It also means the utility work involves more than a simple meter pull, which can affect scheduling.
Sub-Panel Work at the Same Time
Adding a sub-panel for a detached garage, workshop, or addition during the same visit is common. That work happens after the main panel is complete, and can add 2–4 hours depending on distance and conduit routing.
Permit Timing
Connecticut towns vary in how quickly they can schedule an electrical inspection. Most schedule same-day or next-day for panel upgrades. A few require more lead time. We pull the permit before the job begins and schedule the inspection for as close to completion as possible — but if a particular town’s inspector is backed up, that can push the utility reconnect to the next available window.
What Doesn’t Add Time
A few things homeowners assume will slow the job actually don’t:
Old wiring in the house — the panel upgrade doesn’t touch your branch circuit wiring. Whether you have Romex from 1985 or older wiring types, we’re landing those wires on a new panel, not replacing them. Rewiring is a separate scope of work.
Number of rooms — what matters is number of circuits, not square footage. A 2,000 sq ft home with 30 well-organized circuits is faster than a smaller home where the previous electrician ran circuits in an unclear order.
The existing panel brand — unless it’s a hazardous panel that requires extra care in removal (FPE, Zinsco), the brand of the old panel doesn’t meaningfully affect timing.
What the Homeowner Needs to Do
Your responsibilities on the day of the job are minimal:
- Be home, or have someone accessible — we need access to the panel and may have questions during the job
- Clear the panel area — move anything stored in front of or around the electrical panel before we arrive
- Have extension cords ready for anything that genuinely can’t be without power for a few hours
- Know your garage door manual release — locate it before power goes off
We handle everything else: permit, utility coordination, inspection scheduling, and cleanup.
When to Plan for Two Days
Most residential panel upgrades in Connecticut are one-day jobs. Plan for two days when:
- 400A service upgrade — these jobs involve more utility coordination and often a full service entrance replacement that takes longer on both the electrical and utility side
- Major service entrance work — if the mast, meter base, and service entrance conductors all need replacement, that’s a longer job
- Utility scheduling in certain towns — if the utility can’t commit to a same-day reconnect, your power is off overnight
- Sub-panel addition plus main panel — if you’re adding both a new main panel and a sub-panel for a detached structure, budget for a full two-day project
We’ll tell you upfront which category your job falls into.